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Chemoresistance is one of the main obstacles in the clinical treatment of cancer. However, secondary resistance to paclitaxel poses new challenges for cancer treatment. Long noncoding RNAs regulate cellular functions at different levels and mechanisms and play an important role in the biological behavior of tumors.LncRNA microarrays were used to detect lncRNAs in Paclitaxel-resistant cells and corresponding parental cells. Cell counting kit 8 and Transwell analysis were used to test the effect of lncRNA on function.The expression of lncRNA DBH-AS1 in TE-4 TAX-R cells was significantly higher than that in TE-4 cells. Transwell analysis showed that the overexpression of lncRNA DBH-AS1 increased the invasion of Eca cells. Cell scratches and Transwell analysis showed that the overexpression of lncRNA DBH-AS1 in Eca cell culture supernatants promoted the migration and invasion of HUVEC. In addition, lncRNA DBH-AS1 relies on miR-21 to regulate the expression of YOD1.Paclitaxel-resistant lncRNA DBH-AS1 appears to promote ECa cell proliferation and invasion by acting as a ceRNA and regulating miR-21-5p /YOD1 signaling pathway.

Background Although tremendous strides have been made in the participation of women in medicine, female continues to be underrepresented in leadership positions and higher-level academic medicine. An important factor in determining career advancement in academic medicine is the quality and quantity of an individual’s scholarly publications. To date, no study has looked at female authorship in gastroenterology (GI) randomized control trials (RCTs), which remains the gold standard for evaluating intervention effectiveness. Purpose The primary outcome is to assess female authorship in gastroenterology randomized control trials from 2011 to 2021, and the secondary outcome is to assess female authorship within GI subspecialty RCT publications. Method In this observational study, the gender of the first and last author of gastroenterology RCTs from January 1, 2011 to December 31, 2021 was assessed. Python (v3.8.12) was used to extract publication data from PubMed. A validated algorithm, genderize.io, was used to determine gender. Author first names that cannot be determined by the algorithm were manually searched on publicly-available profiles. Result(s) A total of 5690 original gastroenterology RCTs were included from January 1, 2011 to December 31, 2021. The gender of the first and senior authors of the papers was determined for 5668 (99.6%) first authors and 5656 (99.4%) senior authors. Overall, 1937 (34.1%) of the first authors and 1138 (20.0%) of senior authors were female. There was an increase in the proportion of female first authors over the past decade, from 25.4% in 2011 to 37.8% in 2021 (p Within GI subspecialties, 612 RCTs were included for inflammatory bowel disease, 1143 RCTs were included for hepatology, and 1856 RCTs were included for therapeutic endoscopy from January 1, 2011 to December 31, 2021. Further analysis will be performed to determine the gender trend for GI subspecialties. Image Conclusion(s) Female authorship in gastroenterology RCTs has increased from 2011 to 2021, although the rate of senior authorship has increased to a slower extent compared to first authors. Across all years, female authorship in gastroenterology RCTs has been lower than males. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

Some patients with rheumatoid arthritis (RA) will recur despite they have achieved clinical remission after treatment. The subclinical synovitis detected by ultrasonography (US) may be one of the main causes of the RA recurrence. The aim of this study is to establish a nomogram for predicting the outcome of RA patients with disease in clinical remission.One hundred and sixty-seven RA patients who achieved clinical remission and were willing to receive a 1-year follow-up were included in this study. Their demographic, clinical, and laboratory characteristics were recorded at baseline. 7-joints ultrasound (US7) synovitis score (simplified from US7 score) were evaluated at baseline and at the end of follow-up (or when RA recurrence confirmed). All patients were divided into recurrence group and non-recurrence group after the follow-up. Multivariable regression was applied to link the predictors that were significant at p0.05 in the univariate analysis and the recurrence of RA patients in clinical remission, which was served as the basis of the nomogram.Fifty-one RA patients were included in the recurrence group and 116 patients in the non-recurrence group. All US7 synovitis scores in this study showed excellent reproducibility. Multivariable analysis revealed that high-titer positive anti-cyclic citrullinated peptide (anti-CCP), simplified clinical disease activity index (SDAI), baseline grayscale ultrasound (GSUS) score, and baseline power Doppler ultrasound (PDUS) score were the independent predictors for RA recurrence within 1 year. A nomogram incorporating the independent predictors was constructed to predict the risk of RA recurrence. The nomogram showed good discrimination (C-index=0.826) and good calibration.The nomogram incorporating anti-CCP, SDAI, and subclinical synovitis helps to achieve complete remission and reduces the risk of short-term recurrence of RA patients.

ZnSe quantum dots (QDs) were synthesised by the cation-inverting-injection method in aqueous solution, using thioglycolic acid (TGA) as a stabiliser, zinc acetate dihydrate (Zn(OAc)2·2H2O) and sodi...

Summary The genus Echinochloa (Poaceae) includes numerous problematic weeds over a wide range of ecoregions in the world. To date, molecular markers for species identification and assessing phylogenetic relationship are still limited in the genus Echinochloa. In this study, we developed seven chloroplast molecular markers based on divergent chloroplast regions of E. crus-galli and E. oryzicola. Furthermore, Marker #1 (psbA) was examined in more than 200 Echinochloa accessions and a phylogenetic tree grouped these Echinochloa accessions into four clades. Additionally, two different E. crus-galli varieties (E. crus-galli var. crus-galli, E. crus-galli var. praticola) and E. colona were successfully distinguished by this marker. The developed molecular markers contribute to better identification of Echinochloa taxa.

Stagflation refers to the terrible economic malaise associated with declining growth, hyperinflation and high unemployment. Unlike previous cost-push explanations such as an overheated labour market and oil prices, this article suggests that social benefit expenditures are a potential cause of stagflation. We investigate the impact of social benefit expenditures on stagflation in the U.S. over the 1950–2014 period by employing an autoregressive distributed lag (ARDL) bounds testing approach to cointegration, which was developed by Pesaran, Shin, and Smith. The influence of social benefit expenditures on economic growth and inflation and unemployment rates is estimated. The empirical results from the U.S. suggest that economic growth responds negatively to social benefit expenditures, while inflation and unemployment rates are both positively associated with social benefit expenditures. Thus, government-led rigid welfare could contribute to stagflation in the U.S. Instead of increasing people’s hap...

This article investigates the impact of sales tax on economic growth in the United States during the 1960–2013 period using the autoregressive distributed lag bounds testing approach of cointegration. We estimate the long- and short-run elastic coefficients of sales tax on growth and find that economic growth in the United States responds negatively to sales tax in the long run, although it produces positive effects in the short run.

Ti-MCM-41 were synthesised by one-step method using sodium silicate extracted from iron ore tailing as silicon source, tetrabutyl titanate as titanium source and cetyltrimethylammonium bromide as the template. The effects of various experimental parameters, such as molar ratio of Si/Ti, reaction temperature and time, were investigated. The as-synthesised samples were further characterised by X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron micrographs, N2 absorption–desorption and transmission electron microscopy techniques. The results indicated that Ti-MCM-41 materials possessed the ordered hexagonal mesostructure and high surface area.

BACKGROUND The aim of this study was to study the mechanism of miRNA-497 in the apoptosis of osteosarcoma cells. METHODS MG-63 cells were divided into the three groups: NC, BL and miRNA groups, NC group were treated with nothing; BL group were transfected with blank vector; miRNA group were transfected with miRNA-497. Cell proliferation rate was detected by MTT method; Apoptosis rate was detected by flow cytometry and measuring the gene and protein expression of MAPK, Erk and P 21 by RT-PCR and Western blot. RESULTS The cell proliferation rate of miRNA group was significantly lower compared to NC group and BL group (p < 0.05); while the apoptosis rate of miRNA group (32.17 ± 3.23 %) was significantly higher than that of NC group (8.40 ± 1.78 %) and BL group (8.83 ± 0.99 %) (p < 0.05, respectively). Regarding the gene expression detection, we found that gene and protein expressions of MAPK, Erk and P21 of miRNA group were significantly different compared to NC and BL groups (p < 0.05, respectively). CONCLUSION MiR-497 can activate P21 expression by inhibiting the expression of MAPK/Erk signaling pathway, thus promoting the apoptosis of osteosarcoma cells (Fig. 5, Ref. 18).

Epigenetic inactivation of Ras-associated domain family 1A (RASSF1A) by hyper-methylation of its promoter region has been identified in various cancers. However, the role of RASSF1A in renal cancer has neither been thoroughly investigated nor reviewed. In this study, we reviewed and performed a meta-analysis of 13 published studies reporting correlations between methylation frequency of the RASSF1A promoter region and renal cancer risk. The odds ratios (ORs) of eligible studies and their corresponding 95% confidence intervals (95%CIs) were used to correlate RASSF1A promoter methylation with renal cell cancer risk and clinical or pathological variables, respectively. RASSF1A promoter methylation was significantly associated with the risk of renal cell cancer (OR = 19.35, 95%CI = 9.57-39.13). RASSF1A promoter methylation was significantly associated with pathological tumor grade (OR = 3.32, 95%CI = 1.55-7.12), and a possible positive correlation between RASSF1A promoter methylation status and tumor stage was noted (OR = 1.89, 95%CI = 1.00-3.56, P = 0.051). Overall, this meta-analysis demonstrated that RASSF1A promoter methylation is significantly associated with increased risk of renal cell cancer. RASSF1A promoter methylation frequency was positively correlated with pathological tumor grade, but not the clinical stage. This study showed that RASSF1A promoter methylation could be utilized to predict renal cell cancer prognosis.

Numerous zinc oxide (ZnO) nanomaterials, with unique physical and chemical properties, have recently been synthesised by various methods. In this study, a hydrothermal method was developed to synthesise ZnO nanomaterials with different morphologies on indium doped tin oxide (ITO), and the growth mechanism was discussed. The structure and morphologies of the synthesised samples were characterised by X-ray diffraction and SEM. The photoluminescence (PL) and field emission characteristics of ZnO nanomaterials with different morphologies were measured. X-ray diffraction and SEM images indicate that ZnO with morphologies of nanocones, nanorods and nanotubes is grown along c axis to the ITO substrates. The room temperature PL spectra reveal a strong and sharp ultraviolet emission band at 386 nm and a weak blue emission band at 470 nm. The field emission measurements show that the turn-on field of ZnO nanocones, nanorods and nanotubes at emission current density of 10 μA cm−2 is approximately 2·62, 4·31 ...

For the purpose of investigating the potential use of conducting polymers, i.e. polyaniline (PANi), as electrode coating material for improving the function of neural probes, a PANi-coated platinum (Pt) electrode was prepared by the in situ polymerization method. Protein adsorption was observed by atomic force microscopy/scanning electron microscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis, as well as quantification. Peroxidation of rat retinas was evaluated by determination of conjugated dienes and PLOOH, which were quantified by UV-visible spectrophotometer and high-performance liquid chromatography. The stability of PANi coating for 6 months was also estimated with an in vitro electrical stimulation system. This revealed that: (1) PANi with regular and compact nanoparticles 20-40 nm in diameter was successfully polymerized on the uncoated platinum electrode surface; (2) the PANi-coated Pt electrode adsorbed fewer retinal fragments and induced less peroxidation than the uncoated platinum electrode; (3) in contrast to the uncoated platinum electrode, the PANi-coated Pt electrode surface tended to aggregate retinal fragments rather than spread them, which may help to reduce inflammation and scar formation in long-term implantation; (4) the PANi coating exhibited excellent properties in terms of the intactness and the stable nanoparticle morphology after 6 months' electrical stimulation, while corrosion occurred on the uncoated platinum electrode after 1 month.

Using genetic markers defined previously in the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA), isotopic, and non-isotopic polymerase-chain-reaction-coupled single-strand conformation polymorphism (SSCP) were utilized to identify each of three anisakid species [Anisakis simplex (s.l.), Contracaecum osculatum (s.l.), and Hysterothylacium aduncum] from different host species and geographical locations in Poland and Sweden. While subtle microheterogeneity was observed within each of Anisakis simplex (s.l.) and H. aduncum, distinct SSCP profiles were displayed for each of the three species, allowing identification and differentiation of the three taxa. Subsequent sequencing of the ITS-1 and ITS-2 rDNA revealed that A. simplex (s.l.) represented Anisakis simplex s.s. and Contracaecum osculatum (s.l.) represented C. osculatum C. Application of the non-isotopic SSCP assay of ITS-2 to larval anisakid samples from different hosts and geographical locations in China revealed three distinct SSCP profiles, one of which was consistent with that of A. simplex (s.l.), and the other two had different SSCP profiles from that of C. osculatum C and H. aduncum. Sequencing of the ITS-1 and ITS-2 rDNA for representative Chinese anisakid samples examined revealed three anisakid species in China, i.e., Anisakis typica, Anisakis pegreffii, and Hysterothylacium sp. These molecular tools will be useful for identification and investigation of the ecology of anisakid nematodes in China and elsewhere.

Natural attenuation remediation is based on the intrinsic attenuation capacities of the subsurface. Geochemistry of the subsurface controls the fate, transport, transformation, and bioavailability of contaminants. This paper demonstrates that interfacial reactions (e.g., adsorption, desorption, oxidation, or reduction) between arsenic and minerals play an important role in the natural attenuation of arsenic, and could present important pathways for arsenic cycling in the subsurface environment. Iron oxides and kaolinites were used for this experimental study. Based on the different behavior of minerals, it is suggested that some types of minerals can act as mineral indicators for site characterization. Integration of mineralogical and geochemical indicator parameters would greatly improve the quality of site characterization. The current MCL in the USA for arsenic in drinking water may soon be lowered to 5 µg/L. It is estimated that lowering the arsenic MCL would cost billions of dollars per year. The natural attenuation could be a potential cost-effective approach for solving the problem of arsenic-contaminated groundwater.

To learn how nebulin functions in the assembly and maintenance of I-Z-I bands, MYC- and GFP- tagged nebulin fragments were expressed in primary cultured skeletal myotubes. Their sites of incorporation were visualized by double staining with anti-MYC, antibodies to myofibrillar proteins, and FITC- or rhodamine phalloidin. Contrary to expectations based on in vitro binding studies, none of the nebulin fragments expressed in maturing myotubes were incorporated selectively into I-band approximately 1.0-micrometer F-alpha-actin-containing thin filaments. Four of the MYC/COOH-terminal nebulin fragments were incorporated exclusively into periodic approximately 0.1-micrometer Z-bands. Whereas both anti-MYC and Rho-phalloidin stained intra-Z-band F-alpha-actin oligomers, only the latter stained the pointed ends of the polarized approximately 1.0-micrometer thin filaments. Z-band incorporation was independent of the nebulin COOH-terminal Ser or SH3 domains. In vitro cosedimentation studies also demonstrated that nebulin SH3 fragments did not bind to F-alpha-actin or alpha-actinin. The remaining six fragments were not incorporated into Z-bands, but were incorporated (a) diffusely throughout the sarcoplasm and into (b) fibrils/patches of varying lengths and widths nested among normal striated myofibrils. Over time, presumably in response to the mediation of muscle-specific homeostatic controls, many of the ectopic MYC-positive structures were resorbed. None of the tagged nebulin fragments behaved as dominant negatives; they neither blocked the assembly nor induced the disassembly of mature striated myofibrils. Moreover, they were not cytotoxic in myotubes, as they were in the fibroblasts and presumptive myoblasts in the same cultures.

To explore the roles of specific domains of sarcomeric alpha-actinin (s-alpha-actinin) in the assembly and maintenance of striated myofibrils, myogenic cultures were transfected with four MYC-tagged s-alpha-actinin peptides. They were: (1) full-length sarcomeric alpha-actinin, (2) an N-terminal deletion that removed the actin-binding site only (MYC/A-), (3) a peptide that consisted of the actin-binding site only (MYC/A+), and (4) an N-terminal deletion that removed the EF-hands and titin-binding domains (MYC/EFT-). While cytotoxic in replicating myogenic cells, as they were in PtK2 cells, the four MYC peptides were not cytotoxic in postmitotic myotubes. In myotubes each of the four different MYC peptides were promptly and selectively incorporated into normal Z bands. The incorporation of MYC/A-, MYC/A+, and MYC/EFT- into Z bands suggests that (a) the actin-binding site, (b) the spectrin-repeats believed to be responsible for anti-parallel dimerization, and (c) the C-terminal EF-hands and titin-binding domains are each dispensable for targeting s-alpha-actinin/MYC peptides into Z bands. These findings could not have been predicted from the behavior of alpha-actinin (a) in binding assays in cell-free systems or (b) when expressed in transfected nonmuscle cells.

To understand the multiple roles of alpha-actinin in the assembly of (1) Z bands in muscle, and (2) a variety of cytoskeletal structures in non-muscle cells, 4 sarcomeric alpha-actinin derived cDNAs tagged with a MYC epitope were constructed. The constructs were: (1) full-length (FL/MYC); (2) minus EF-hands (-EF/MYC); (3) actin-binding site (+A/MYC); and (4) minus actin-binding site (-A/MYC). These four cDNAs were individually transfected into PtK2 cells. The exogenous sarcomeric alpha-actinin (s-alpha-actinin/MYC) was followed with labeled anti-MYC, the endogenous non-sarcomeric alpha-actinin (non-s-alpha-actinin) with labeled anti-non-s-alpha-actinin. The salient findings were: (1) the selective intracellular localizations of each expressed MYC-tagged peptide differed one from the other; (2) their respective localizations in the 10-24-h post-transfection (p.t.) period differed from their localizations in the 48-72-h p.t. period; (3) each MYC-positive peptide was cytotoxic, but each in a distinctive way; and (4) while the selective targeting of FL/MYC to dense bodies, adhesion plaques, adherens junctions, and ruffled membranes was consistent with binding studies in cell-free systems, the incorporation of the mutated peptides, particularly +A/MYC and -A/MYC was not. Changes in localization over time and the distinctive cytopathologies probably reflect domain-specific targeting. They also suggest unexpected cooperative involvement of multiple domains of alpha-actinin with specific receptors in distal cytoskeletal structures. To date, such qualitative in vivo interactions have not been described either in in vitro binding studies, or in short-term experiments involving localization and/or fate of microinjected labeled molecules into living cells.

A high-intensity electron field emission was obtained from a SiC∕Si heterostructure, which was formed by high temperature carbon implantation into silicon. Densely distributed sharp tips were easily obtained at the interface of the SiC∕Si heterostructure by post-implantation etching off the top Si. A low turn-on field of 2.6V∕μm was observed with samples formed by 160keV carbon implantation with a dose of 8.0×1017cm−2. The existence of the densely distributed small protrusions was considered as the main reason for efficient emission.

The earliest expression of truncated desmin in transfected PtK2 cells results in the formation of dispersed microprecipitates containing not only the truncated desmin, but also endogenous vimentin and cytokeratin proteins. Desmin microprecipitates without vimentin or vimentin microprecipitates without desmin are not observed. The microprecipitates involving cytokeratin invariably are also positive for desmin and vimentin. Over time, the precipitates enlarge into 1- to 2-microns spheroids and then fuse into amorphous chimeric juxtanuclear masses that can occupy > 30% of the cell volume. Concurrently, first the vimentin and then the cytokeratin networks are resorbed. The chimeric precipitates are not recognized or marked for degradation by the lysosomal system. Ultimately the cell nucleus fragments and the cell dies. Similar protein complexes appear in many human and animal pathologies, suggesting that a similar protein-precipitation sequence initiated by the introduction of a mutationally or environmentally altered protein molecule is at work.

Our previous studies showed that the alcohol extract of the fruit of Brucea javanica (Fructus Bruceae) possessed significant cytotoxicity in pancreatic adenocarcinoma cell lines. A bioassay-guided fractionation and purification resulted in the isolation and characterization of seven quassinoids including brusatol, bruceine D, bruceine H, yadanzioside A, yadanzioside G, javanicoside C and bruceantinoside A. Among them, brusatol exhibited the most potent in vitro antipancreatic cancer action, with IC(50) values of 0.36 µm and 0.10 µm on PANC-1 and SW1990 cell lines, respectively. This is the first report on the antipancreatic adenocarcinoma activity of brusatol.

In many nonmuscle cells, nonsarcomeric alpha-actinin is distributed in the dense bodies of stress fibers, adhesion plaques, and adherens junctions. In striated muscle, a sarcomeric isoform of alpha-actinin (s-alpha-actinin) is found in the Z-bands of myofibrils and subsarcolemmal adhesion plaques. To understand the role(s) of the alpha-actinin isoforms in the assembly and maintenance of such cytoskeletal structures, full-length or truncated s-alpha-actinin cDNAs were expressed in PtK2 cells and in primary skeletal myogenic cells. We found the following. (i) In transfected PtK2 cells the truncated s-alpha-actinin was rapidly incorporated into preexisting dense bodies, adhesion plaques, and adherens junctions. With time these structures collapsed, and the affected cells detached from the substrate. (ii) In myotubes the truncated s-alpha-actinin was incorporated into nascent Z-bands. Many of these progressively hypertrophied, forming nemaline-like bodies. With time the affected myofibrils fragmented, and the myotubes detached from the substrate. (iii) In both cell types the truncated s-alpha-actinin was significantly more disruptive of the cytoskeletal structures than the full-length molecule. (iv) Pools of "over-expressed" full-length or truncated protein did not self-aggregate into homogeneous, amorphous complexes; rather the exogenous proteins selectively colocalized with the same cohort of cytoskeletal proteins with which the endogenous alpha-actinin normally associates. The similarity among the hypertrophied Z-bands in transfected myotubes, the nemaline bodies in patients with nemaline myopathies, and the streaming Z-bands seen in various muscle pathologies raises the possibility that the genetically determined nemaline bodies and the pathologically induced Z-band alterations may reflect primary and/or post-translational modifications of s-alpha-actinin.

Psoriasis is a skin disease associated with hyperproliferation and aberrant differentiation of keratinocytes. Our previous studies have identified the root of Rubia cordifolia L. as a potent antiproliferative and apoptogenic agent in cultured HaCaT cells (IC(50) 1.4 microg/ml). In the present study, ethanolic extract of Radix Rubiae was fractioned sequentially with hexane, ethyl acetate (EA), n-butanol and water. EA fraction was found to possess most potent antiproliferative action on HaCaT cells (IC(50) 0.9 microg/ml). Mechanistic study revealed that EA fraction induced apoptosis on HaCaT cells, as it was capable of inducing apoptotic morphological changes. Annexin V-PI staining assay also demonstrated that EA fraction significantly augmented HaCaT apoptosis. In addition, EA fraction decreased mitochondrial membrane potential in a concentration- and time-dependent manner. The standardized EA fraction was formulated into topical gel and its keratinocyte-modulating action was tested on mouse tail model. EA fraction dose-dependently increased the number and thickness of granular layer and epidermal thickness on mouse tail skin, indicative of the keratinocyte differentiation-inducing activity. Taking the in vitro and in vivo findings together, the present preclinical study confirms that EA fraction is a promising antipsoriatic agent warranting further development for psoriasis treatment.

Phorbol esters selectively and reversibly disassemble the contractile apparatus of cultured skeletal muscle as well as inhibit the synthesis of many contractile proteins without inhibiting that of housekeeping proteins. We now demonstrate that phorbol esters reversibly decrease the mRNA levels of at least six myofibrillar genes: myosin heavy chain, myosin light chain 1/3, myosin light chain 2, cardiac and skeletal alpha-actin, and skeletal troponin T. The steady-state message levels decrease 50- to 100-fold after 48 h of exposure to phorbol esters. These decreases can be attributed at least in part to decreases in transcription rates. For at least two genes, cardiac and skeletal alpha-actin, some of the decreases are the result of increased mRNA turnover. In contrast, the cardiac troponin T steady-state message level does not change, and its transcription rate decreases only transiently upon exposure to phorbol esters. Phorbol esters do not decrease the expression of the housekeeping genes, alpha-tubulin, beta-actin, and gamma-actin. Phorbol esters do not decrease the steady-state message levels of MyoD1, a gene known to be important in the activation of many skeletal muscle-specific genes. Cycloheximide blocks the phorbol ester-induced decreases in transcription, message stability, and the resulting steady-state message level but does not block the tetradecanoyl phorbol acetate-induced rapid disassembly of the I-Z-I complexes. These results suggests a common mechanism for the regulation of many myofibrillar genes independent of MyoD1 mRNA levels, independent of housekeeping genes, but dependent on protein synthesis.

An expression vector was prepared containing a cDNA coding for a truncated version of the intermediate filament (IF) protein desmin. The encoded truncated desmin protein lacks a portion of the highly conserved alpha-helical rod region as well as the entire nonhelical carboxy-terminal domain. When transiently expressed in primary fibroblasts, or in differentiating postmitotic myoblasts and multinucleated myotubes, the truncated protein induces the complete dismantling of the preexisting vimentin or desmin/vimentin IF networks, respectively. Instead, in both cell types vimentin and desmin are packaged into hybrid spheroid bodies scattered throughout the cytoplasm. Despite the complete lack of intact IFs, myoblasts and myotubes expressing truncated desmin assemble and laterally align normal striated myofibrils and contract spontaneously in a manner indistinguishable from that of control myogenic cells. In older cultures the spheroid bodies shift from a longitudinal to a predominantly transverse orientation and loosely align along the I-Z-I-regions of striated myofibrils (Bennett, G.S., S. Fellini, Y. Toyama, and H. Holtzer. 1979. J. Cell Biol. 82:577-584), analogous to the translocation of intact desmin/vimentin IFs in control muscle. These results suggest the need for a critical reexamination of currently held concepts regarding the functions of desmin IFs during myogenesis.

Cultured cardiac myocytes were stained with antibodies to sarcomeric alpha-actinin, troponin-I, alpha-actin, myosin heavy chain (MHC), titin, myomesin, C-protein, and vinculin. Attention was focused on the distribution of these proteins with respect to nonstriated myofibrils (NSMFs) and striated myofibrils (SMFs). In NSMFs, alpha-actinin is found as longitudinally aligned, irregular approximately 0.3-microns aggregates. Such aggregates are associated with alpha-actin, troponin-I, and titin. These I-Z-I-like complexes are also found as ectopic patches outside the domain of myofibrils in close apposition to the ventral surface of the cell. MHC is found outside of SMFs in the form of discrete fibrils. The temporal-spatial distribution and accumulation of the MHC-fibrils with respect to the I-Z-I-like complexes varies greatly along the length of the NSMFs. There are numerous instances of I-Z-I-like complexes without associated MHC-fibrils, and also cases of MHC-fibrils located many microns from I-Z-I-like complexes. The transition between the terminal approximately 1.7-microns sarcomere of any given SMF and its distal NSMF-tip is abrupt and is marked by a characteristic narrow alpha-actinin Z-band and vinculin positive adhesion plaque. A titin antibody T20, which localizes to an epitope at the Z-band in SMFs, precisely costains the 0.3-microns alpha-actinin aggregates in ectopic patches and NSMFs. Another titin antibody T1, which in SMFs localizes to an epitope at the A-I junction, typically does not stain ectopic patches and NSMFs. Where detectable, the T1-positive material is adjacent to rather than part of the 0.3-microns alpha-actinin aggregates. Myomesin and C-protein are found only in their characteristic sarcomeric locations (even in just perceptible SMFs). These A-band-associated proteins appear to be absent in ectopic patches and NSMFs.

Computer-aided instruction (CAI) has existed for decades. Its third generation system using Internet and Web technologies to deliver university education (so called virtual universities) has been a hot research topic in recent years. However, few such virtual universities have been as successful as expected. Why didn’t eEducation systems turn out to be a silver bullet for virtual universities as expected? What are components and elements that have been missed in current eEducation systems? How can we learn from past experience and lessons so that a conceptual framework could be proposed to design a better next generation eEducation system that could help universities and corporations to gain competitive advantages in a global education market? This research paper tries to explore these important issues. Based upon a comprehensive literature review, a conceptual framework is proposed with the aim of guiding the design of a next generation eEducation system.

To investigate the effect of intermittent pneumatic compression on prevention of deep venous thrombosis after operation of lower limbs.From Oct. 1997 to Aug. 1998, forty cases were received Doppler examination preoperatively, which showed no deep venous thrombosis in all the lower limbs of 40 cases. Among them, 24 cases were received total hip arthroplasties, 4 cases were received total knee arthroplasties and 12 cases were received dynamic hip screw. Postoperatively, every case were continuously received intermittent pneumatic compression for 14 to 21 days (2 hours, qid), and venography were performed on the operated lower limb on the 7th day after operation to check the presence of deep venous thrombosis.Among the 40 cases, there were 4 cases of deep venous thrombosis without symptom of pulmonary embolism, the incidence rate was 10%.Intermittent pneumatic compression can significantly reduce the incidence rate of deep venous thrombosis after the operation of the lower limbs.

To study the mechanisms of partial dominance, 12 intragenic alcohol dehydrogenase null mutations (Adhn) in Drosophila melanogaster were used as a model system. These known sequenced mutations, either single base substitutions or small intragenic deletions (9-16 bp) were analyzed for peptide production, dimer formation and enzymatic activity of the heterodimer. Multiple mechanisms leading to partial enzyme expression in heterozygotes and a wide range of dominance varying from almost complete recessive to a high degree of dominance were found. An expression of partial dominance for alcohol tolerance was observed for all 12 Adhn under the high stress of 10% ethanol. The genetic background on which the null mutations are expressed is a major determinant for alcohol tolerance of the heterozygous adult flies. The mutations induced by X-ray had higher average dominance than that of ENU-induced mutations, and the mutations that formed nonfunctional heterodimers had the highest dominance.

After studying of familial leukemias, Myelodysplastic Syndrome (MDS) and aplastic anemia (AA), we observed and analysed bone marrow (BM) cells hematologically and molecular-cytogenetically in 36 persons who are first degree relatives (FDRs) of patients with acute leukemias (AL), MDS and AA. The peripheral blood (PB) lymphocyte chromosome fragility sensitive to folic acid and unstability was also analysed in 18 FDRs. The abnormal BM megakaryocystic/erythroid cellularity and the rearrangement of c-erbB were found in 66%-86.1% of parents and siblings of patients. The associations of dysplastic megakaryopoiesis, including the presence of lymphoid small megakaryocytes, with the chromosomal monosomy or/and the rearrangement/amplification of C-erbB, were found in a few parents and siblings. These results were consistent with those of MDS, Fanconi Anemia (FA) and AL. The normal karyotype and SCD positive of BM cells and PB lymphocytes, and PB lymphocyte chromosomal fragility and unstability were found in most of patients' parents, while familial chromosomal monosomy of BM cells and PB lymphocyte chromosomal fragility were found in parents and siblings of familial leukemia patients. Based on the studies of a large family with 7 cases of acute erythroleukamia and relative myeloleukemias in three consecutive generations and a family with 3 CAA and 1 AML, the rearrangement of c-erbB might be inherited. The rearrangement/amplification of c-erbB and its PCR detected results could be the indicators of gene diagnosis of preleukemia and might be useful in genetic conselling of leukemias. The common origin of AL, MDS and AA was discussed.

Normal cell physiological processes rely heavily on cues from the extracellular environment to coordinate the proper functioning of cellular activities. The intercellular communication that takes place through gap junctions in neighboring cells has been implicated in growth control and embryonic differentiation. Indeed, many tumorigenic cells induced to overexpress gap junction proteins exhibit increased differentiation and decreased cell proliferation. Although absent in mature skeletal muscle, studies have demonstrated that gap junctions are present during the early stages of myogenesis, indicating their possible role in muscle development. In our present study, we have attempted to induce a more differentiated phenotype in communication-deficient rhabdomyosarcoma cells. These tumorigenic human cells were transfected with cDNA encoding the gap junction protein connexin43 (Cx43) such that clones of varying expression were isolated. Intercellular communication as measured with dye passage assays was directly proportional to the level of Cx43 expressed, and in those cells expressing Cx43 at high levels, a marked increase in cell membrane fusion and myosin expression was observed. Furthermore, clones expressing Cx43 at high levels exhibited a significant reduction in growth rate when grown under nonadhesive conditions, an indication that their tumorigenicity had been reduced. This apparent increase in myogenic differentiation lends further evidence to the possible role of gap junctional coupling during developmental processes.