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Silk gland cells of silkworm larvae undergo multiple cycles of endomitosis for the synthesis of silk proteins during the spinning phase. In this paper, we analyzed the endomitotic DNA synthesis of silk gland cells during larval development, and found that it was a periodic fluctuation, increasing during the vigorous feeding phase and being gradually inhibited in the next molting phase. That means it might be activated by a self-regulating process after molting. The expression levels of cyclin E, cdt1 and pcna were consistent with these developmental changes. Moreover, we further examined whether these changes in endomitotic DNA synthesis resulted from feeding or hormonal stimulation. The results showed that DNA synthesis could be inhibited by starvation and re-activated by re-feeding, and therefore appears to be dependent on nutrition. DNA synthesis was suppressed by in vivo treatment with 20-hydroxyecdysone (20E). However, there was no effect on DNA synthesis by in vitro 20E treatment or by either in vivo or in vitro juvenile hormone treatment. The levels of Akt and 4E-BP phosphorylation in the silk glands were also reduced by starvation and in vivo treatment with 20E. These results indicate that the activation of endomitotic DNA synthesis during the intermolt stages is related to feeding and DNA synthesis is inhibited indirectly by 20E.

GlutathioneS-transferases (GSTs, EC 2.5.1.18) are a family of super enzymes with multiple functions that play a major role in the detoxification of endogenous and xenobiotic compounds. In our previous study, we have predicted 23 putative cytosolic GSTs in the silkworm genome using bioinformatic methods. In this study, we cloned and studied the insect-specific epsilon-class GST geneGSTe4from the silkworm,Bombyx mori. The recombinantBmGSTe4(Bac-BmGSTe4) was overexpressed in SF-9 cell lines, and it was found to have effective GST activity. We also found that the expression ofBmGSTe4was especially down-regulated after the silkworms were fumigated with or ingested phoxim. Moreover,BmGSTe4protected HEK293 cells against UV-induced cell apoptosis. These results demonstrated thatBmGSTe4has GST activity, is sensitive to phoxim, and plays a role in inhibition of UV-induced cell apoptosis.

Silk gland cells undergo multiple endomitotic cell cycles during silkworm larval ontogeny. Our previous study demonstrated that feeding is required for continued endomitosis in the silk gland cells of silkworm larvae. Furthermore, the insulin signaling pathway is closely related to nutritional signals. To investigate whether the insulin signaling pathway is involved in endomitosis in silk gland cells, in this study, we initially analyzed the effects of bovine insulin on DNA synthesis in endomitotic silk gland cells using 5-bromo-2'-deoxyuridine (BrdU) labeling technology, and found that bovine insulin can stimulate DNA synthesis. Insulin signal transduction is mainly mediated via phosphoinositide 3-kinase (PI3K)/Akt, the target of rapamycin (TOR) and the extracellular signal-regulated kinase (ERK) pathways in vertebrates. We ascertained that these three pathways are involved in DNA synthesis in endomitotic silk gland cells using specific inhibitors against each pathway. Moreover, we investigated whether these three pathways are involved in insulin-stimulated DNA synthesis in endomitotic silk gland cells, and found that the PI3K/Akt and TOR pathways, but not the ERK pathway, are involved in this process. These results provide an important theoretical foundation for the further investigations of the mechanism underlying efficient endomitosis in silk gland cells.

Orbital angular momentum (OAM) is a general characteristic of coherent bosonic matter waves. Partially coherent bosonic matter waves (PCMWs) can also have OAM according to a vortex or twisted structure of the correlation phase of the first-order correlation function. We theoretically prove that a twist phase exists under partial coherence, and this phase contributes to the OAM flux of the PCMW field. We also present an example which illustrates that a twist phase can be produced by illuminating a Gaussian Schell model cold atomic cloud with a sequence of cylindrical lens pulses.

DNA replication is rigorously controlled in cells to ensure that the genome duplicates exactly once per cell cycle. Geminin is a small nucleoprotein, which prevents DNA rereplication by directly binding to and inhibiting the DNA replication licensing factor, Cdt1. In this study, we have identified 2 Geminin genes, BmGeminin1 and BmGeminn2, in silkworm, Bombyx mori. These genes contain the Geminin conserved coiled-coil domain and are periodically localized in the nucleus during the S-G2 phase but are degraded at anaphase in mitosis. Both BmGeminin1 and BmGeminin2 are able to homodimerize and interact with BmCdt1 in cells. In addition, BmGeminin1 and BmGeminin2 can interact with each other. Overexpression of BmGeminin1 affects cell cycle progression: cell cycle is arrested in S phase, and RNA interference of BmGeminin1 leads to rereplication. In contrast, overexpression or knockdown of BmGeminin2 with RNAi did not significantly affect cell cycle, while more rereplication occurred when BmGeminin1 and BmGeminin2 together were knocked down in cells than when only BmGeminin1 was knocked down. These data suggest that both BmGeminin1 and BmGeminin2 are involved in the regulation of DNA replication. These findings provide insight into the function of Geminin and contribute to our understanding of the regulation mechanism of cell cycle in silkworm.

Shrinkage instability is currently the main difficulty that occurs during the production of cashmere sweaters manufactured with high-count worsted yarns. By evaluating the details at various processing stages, four factors that affect the shrinkage of high-count yarn cashmere sweaters are determined, including the quality indexes of cashmere fiber, the decolorizing process, the yarn counts, and the dyeing process. The shrinkage regularities are shown in these aspects: the longer the cashmere fiber, the lower the yarn/clothing shrinkage; the greater the fiber strength, the lower the yarn/clothing shrinkage; the more the yarn count, the larger the yarn/clothing shrinkage. The shrinkage of natural white cashmere is lower than that of natural color (gray or brown) cashmere. The shrinkage of decolorized cashmere becomes larger than that of natural color cashmere, but the shrinkage of dyed cashmere (especially with weak acid dyes) is even greater than that of the decolorized fiber. These results should lead to the development of some practical processes and appropriate measures to control the high and unstable shrinkage of the cashmere sweater.

Combustion behavior of indigenous lignite in oxygen-enriched conditions was investigated by using thermogravimetric analyzer (TGA). Combustion tests were carried out in different oxygen concentration (21%O2/79%N2, 30%O2/70%N2, 40%O2/60%N2, 50%O2/50%N2, 60%O2/40%N2, 70%O2/30%N2). Then get the characteristic temperatures. . The model-fitting mathematical approach was used to evaluated the kinetic triplet (f (α),E,A) through Gorbatchev method. The combustion stages were divided into the early combustion stage and the later combustion stage. The calculation showed that the kinetics parameters higher in the early combustion stage than that in the later combustion stage.

The characteristics of Sheng Li (China) Lignite combustion under oxygen-enriched conditions were studied by thermogravimetric analysis , including TGDTG and DTA. Experiments on lignite combustion were carried out under four kinds of oxygen-enriched conditions (O2/N2mixture atmospheres) and with a heating rate of 10°C/min. The experiments of working temperature range was 20°C-900°C. The combustion process, regarded as the first order reaction, was analyzed through the Gorbachev kinetic equation participants, which gained the conclusion that Sheng Li lignite combustion reaction shift to low temperature zone and kinetic parameters of combustion increase gradually when oxygen concentration increase.

To meet the requirements of construction convenience and protection level for concrete bridge barrier, this article researches the base form of detached and re-installed barriers. Considering integrity and dismounting convenience, four base forms were put forward such as anchor bolt connected base,outside embedded base, inside embedded base and steel bar welded base. The four base forms were compared through computer simulation, bogie test and analysis of construction convenience. The researches show that there are more probability for inside embedded base and outside embedded base to overturn in practical application. The anchor bolt is likely to cause stress concentration of connection location, and difficult to install. Rigid connection between barrier and bridge frange plate was formed by base steel welded with anchor plate, and so the integrity is better and the construction is convenient and feasible. And so steel bar welded base is the best and suitable for application in the project.

The silk gland is an important organ in silkworm as it synthesizes silk proteins and is critical to spinning. The genomic DNA content of silk gland cells dramatically increases 200-400 thousand times for the larval life span through the process of endomitosis. Using in vitro culture, DNA synthesis was measured using BrdU labeling during the larval molt and intermolt periods. We found that the cell cycle of endomitosis was activated during the intermolt and was inhibited during the molt phase. The anterior silk gland, middle silk gland, and posterior silk gland cells asynchronously exit the endomitotic cycle after day 6 in 5th instar larvae, which correlated with the reduced expression of the cell cycle-related cdt1, pcna, cyclin E, cdk2 and cdk1 mRNAs in the wandering phase. Additional starvation had no effect on the initiation of silk gland DNA synthesis of the freshly ecdysed larvae.

Combustion curves of lignite samples from China in four different particle sizes and Oxygen-enriched condition were analyzed using non-isothermal thermogravimetric method. The lignite samples separated into -150+100 μm, -100+75 μm, -75+50 μm, and -50μm sizes. Combustion profiles shift to lower temperature zone as particle size decrease. Combustion profiles have little difference when the particle size below 100 μm in oxygen atmosphere; Oxygen-enriched combustion experiment were carried out in O2/N2 mixture atmospheres with the volume fraction of oxygen was 21%, 30%, 40%, 50%, 60% and 70%, respectively. As oxygen concentration increase profiles shift to lower temperature zone. and gets the proper range of oxygen concentration is about 50%.

The instability identification of goaf risky is an important work in the mine engineering. Based on distance discriminant analysis, a method to identify the instability of goaf risky in mines was presented in this paper. Nine factors influencing the stability of goaf risky, including uniaxial compressive strength of rock, elastic modulus of rock, rock quality designation (RQD), area ration of pillar, ratio of width to height of pillar, depth of ore body, volume of goaf, dip of ore body and area of goaf, were selected as discriminant indexes in the stability analysis of goaf. The actual data of 40 goafs were used as training samples to establish a discriminant analysis model to identify the stability of goaf. The results show that this discriminant analysis model has high precision and misdiscriminant ratio is 0.025 in re-substitution process. The instability identification of a metal mine was discriminanted by using this model and the identification result is identical with that of practical situation.

Apoptosis is a known regulator of morphogenetic events. In mammals, the critical role of oxidative stress-induced apoptosis has been well-studied; however, in insects the role of oxidative stress in apoptosis is not clear. In a previous study, we showed that apoptosis-related genes are present in the silkworm Bombyx mori, an important lepidopteran insect model. In this study, we evaluated the effect of H2O2-induced oxidative stress on apoptosis, reactive oxygen species (ROS) levels, mitochondrial response, cytochrome c release and apoptosis-related gene expression in the BmN-SWU1 cell line from B. mori ovaries. Our results showed that BmN-SWU1 cells exposed to H2O2 showed cell protuberances, cytoplasmic condensation, apoptotic bodies, DNA ladder formation and caspase activities indicating apoptosis. H2O2-induced apoptosis also increased intracellular ROS level, changed mitochondrial distribution, reduced mitochondrial membrane potential and increased the release of cytochrome c from mitochondria. Furthermore, western blot analysis revealed a significant increase in p53 and cytochrome c expression, and a decrease in Bcl-2 expression compared to the controls. Moreover, quantitative real-time PCR (qRT-PCR) showed an increase in the transcript levels of BmICE, Bmapaf-1 and BmEndoG by 439.5%, 423.9% and 42.2%, respectively, after treatment with 1 μM H2O2 for 24 h. However, the transcript levels of Bmbuffy declined by 41.4% after 24 h of exposure to 1 μM H2O2. These results show that H2O2 treatment induced apoptosis in BmN-SWU1 cells via the mitochondrial apoptotic pathway. Further, it appears that oxidative stress induced by H2O2 activates both caspase-dependent and caspase-independent mitochondrial apoptotic pathways in silkworm cells. Taken together, these findings improve our knowledge of apoptosis in silkworm and the apoptotic pathways in insects.

Silk gland cells of silkworm larvae undergo multiple cycles of endomitosis for the synthesis of silk proteins during the spinning phase. In this paper, we analyzed the endomitotic DNA synthesis of silk gland cells during larval development, and found that it was a periodic fluctuation, increasing during the vigorous feeding phase and being gradually inhibited in the next molting phase. That means it might be activated by a self-regulating process after molting. The expression levels of cyclin E, cdt1 and pcna were consistent with these developmental changes. Moreover, we further examined whether these changes in endomitotic DNA synthesis resulted from feeding or hormonal stimulation. The results showed that DNA synthesis could be inhibited by starvation and re-activated by re-feeding, and therefore appears to be dependent on nutrition. DNA synthesis was suppressed by in vivo treatment with 20-hydroxyecdysone (20E). However, there was no effect on DNA synthesis by in vitro 20E treatment or by either in vivo or in vitro juvenile hormone treatment. The levels of Akt and 4E-BP phosphorylation in the silk glands were also reduced by starvation and in vivo treatment with 20E. These results indicate that the activation of endomitotic DNA synthesis during the intermolt stages is related to feeding and DNA synthesis is inhibited indirectly by 20E.

Cyclin B is an important regulator of the cell cycle G2 to M phase transition. The silkworm genomic database shows that there are two Cyclin B genes in the silkworm (Bombyx mori), BmCyclin B and BmCyclin B3. Using silkworm EST data, the cyclin B3 (EU074796) gene was cloned. Its complete cDNA was 1665 bp with an ORF of 1536 bp derived from seven exons and six introns. The BmCyclin B3 gene encodes 511 amino acids, and the predicted molecular weight is 57.8 kD with an isoelectric point of 9.18. The protein contains one protein damage box and two cyclin boxes. RNA interference-mediated reduction of BmCyclin B and BmCyclin B3 expression induced cell cycle arrest in G2 or M phase in BmN-SWU1 cells, thus inhibiting cell proliferation. These results suggest that BmCyclin B and BmCyclin B3 are necessary for completing the cell cycle in silkworm cells.

Purpose To explore the correlation between a septal angle measured on computed tomographic pulmonary angiography (CTPA) and pulmonary vascular resistance (PVR) determined by right heart catheterization in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods Eighty-six patients with CTEPH (54 men, mean age: 53.08±12.43 y) were retrospectively reviewed, and 86 sex-matched and age-matched individuals without pulmonary artery hypertension and pulmonary embolism were used as the control group. All patients with CTEPH underwent CTPA before right heart catheterization. Septal angle was measured on transverse CTPA images as the angle between the interventricular septum and the line joining the midpoint of the sternum to the thoracic vertebral spinous process. Hemodynamic PVR was calculated on the basis of the data from right heart catheterization. Results Septal angle was 65.27±12.24 degrees and 39.43±9.79 degrees in the CTEPH group and control group, respectively, which was statistically significant (t=18.139, P=0.000). The septal angle correlated positively with PVR (r=0.629, P=0.000). By stepwise linear regression analysis, the septal angle was shown to be the only variable (r=0.578) that was independently associated with PVR levels, leading to the following equation: PVR=21.591×septal angle-374.641. By receiver operating characteristic analysis, septal angle ≥67.55 degrees had a sensitivity of 71.6% and a specificity of 73.4% for predicting PVR≥1000 dyne s/cm with an area under the curve of 0.739±0.055, which was higher than the area under the curve of right ventricular area/left ventricular area (0.627±0.061) and that of transverse diameter of right ventricle/transverse diameter of left ventricle (0.612±0.060). Conclusion The septal angle is a useful tool for estimating PVR in patients with CTEPH.

To explore the relationship of spinal ventricular septal angle (SVSA) measured by computer tomographic pulmonary angiography (CTPA) and right cardiac functions, N-terminal brain natriuretic peptide (NT-proBNP) in the patients with chronic thromboembolic pulmonary hypertension (CTEPH).Forty-four CTEPH patients, 26 males and 18 females aged (52 ± 12) years old on average, at our hospital from January 2008 to January 2010 were retrospectively reviewed. SVSA and such pulmonary artery obstruction indices as Qanadli and Mastora indices were evaluated by two independent radiologists. The parameters of right heart functions were evaluated by echocardiography and right-heart catheterization. The level of NT-proBNP was measured by enzyme linked immunosorbent assay (ELISA).SVSA was (63 ± 11)° in CTEPH and (40 ± 7)° in the control group. The differences were significant (t = 12.320, P = 0.000). SVSA had a moderately positive correlation with the level of NT-proBNP (r = 0.704, P = 0.000). A positive correlation existed between SVSA and right atrium transverse diameter (r = 0.381, P = 0.002), right atrium long axis diameter (r = 0.437, P = 0.000) and right ventricular transverse diameter (r = 0.449, P = 0.000) on echocardiography. But there was no correlation between SVSA and right ventricular ejection fraction (r = -0.175, P = 0.365, n = 24). Also there was a negative correlation between SVSA and cardiac output (r = -0.337, P = 0.025), cardiac index (r = -0.351, P = 0.020), right cardiac work (r = -0.307, P = 0.043) and right ventricular stroke work (r = -0.384, P = 0.010).Spinal ventricular septal angle measured on CTPA may serve as a better predictor for evaluating the level of NT-proBNP and right cardiac functions in CTEPH.

Objectives The purpose is to identify the role of cardiovascular parameters of computed tomographic pulmonary angiography (CTPA) to assess pulmonary vascular resistance (PVR) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Background The assessment of PVR is of great importance in the management of patients with CTEPH. The role of CPTA in assessment of PVR of CTEPH remains to be explored. Methods Clinical and radiological data of 90 patients (55 men, age 17–84years) with CTEPH were retrospectively reviewed in this study. All patients received CTPA before right-heart catheterization. Cardiovascular parameters and Pulmonary Artery Obstruction Indices including Qanadli Index and Mastora Index were evaluated on CTPA. Hemodynamic PVR was calculated with the standard formula according to data from right-heart catheterization. The correlation of cardiovascular parameters of CTPA and PVR was analyzed. Results In Cardiovascular parameters, neither Qanadli Index(r=0.134, p=0.208) nor Mastora Index (r=0.149, p=0.90) did correlate with PVR. Cobb angle(r=0.613, p=0.000), the ratio of right to left ventricular area(r=0.422, p=0.000)and the ratio of right to left ventricular transverse diameter (r=0.410, p=0.000) respectively correlated with PVR. By receiver operating characteristic curve analysis, a Cobb angle cutoff value of 67.55° had a sensitivity of 72.5% and a specificity of 84.0% to determine PVR ≥1000 (dyn.sec/cm 5 ) and its Area Under Curve is (0.800±0.048). By stepwise linear regression analysis, Cobb angle was only one variable (R=0.601) shown to be independently associated with PVR, leading to the following equation: PVR=25.796×Cobb angle−585.935(F=37.929, p=0.000). Conclusion The analysis of CTPA-derived cardiovascular parameters, especially the Cobb angle, is a reliable tool for estimating PVR in patients with CTEPH, but Pulmonary Artery Obstruction Indices do not correlate with PVR.

To observe the therapeutic effect of digital acupoint pressure for treatment of the nerve root type of cervical spondylosis.Four hundred cases were randomly divided into a digital acupoint pressure group (DAP group) and a medicine group, 200 cases in each group. Acupoints of Quepen (ST 12), Jianjing (GB 21) and Tianzong (ST 11) etc. were used for digital pressing in the DAP group; and Chinese herb medicine of Gentongping was routinely taken in the medicine group. After three treatment courses, the symptoms of pain and numbness, the signs of pressure measurement by compression of head, brachial plexus drawer test and arm myodynamia, as well as the total cumulative scores of daily living capability, were compared.After treatment, the total cumulative scores of numbness, pressure measurement by compression of head, brachial plexus drawer test, arm myodynamia and daily living capability in both groups were obviously better than those of before treatment (all P0.01); but there was a significant difference on the total cumulative score of the symptoms and signs between the two groups. The cured rate of 78.0% and total effective rate of 99.0% in the DAP group were better than those of 61.0% and 87.0% in the medicine group, respectively (both P0.01).Digital acupoint pressure plays an active role in improving the symptoms and signs on patients with nerve root type of cervical spondylosis, which is better than Chinese herb medicine of Gentongping.