• ALGAE
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• v.33 no.1
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• pp.127-141
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• 2018

Low efficiency in microalgal biomass production was largely attributed to the low density of algal cell cultures. Though mutations that reduced the level of chlorophyll or pigment content increased efficiency of photon usage and thus the cell-culture density under high-illumination growth conditions (e.g., >$500{\mu}mol\;photon\;m^{-2}\;s^{-1}$), it was unclear whether algae could increase cell-culture density under low-illumination conditions (e.g., ${\sim}50{\mu}mol\;photon\;m^{-2}\;s^{-1}$). To address this question, we performed forward genetic screening in Chlamydomonas reinhardtii. A pool of >1,000 insertional mutants was constructed and subjected to continuous subcultures in shaking flasks under low-illumination conditions. Complexity of restriction fragment length polymorphism (RFLP) pattern in cultures indicated the degree of heterogeneity of mutant populations. We showed that the levels of RFLP complexity decreased when cycles of subculture increased, suggesting that cultures were gradually populated by high cell-culture density (HCD) strains. Analysis of the 3 isolated HCD mutants after 30 cycles of subcultures confirmed that their maximal biomass production was 50-100% higher than that of wild type under low-illumination. Furthermore, levels of chlorophyll content in HCD mutant strains were similar to that of wild type. Inverse polymerase chain reaction analysis identified the locus of insertion in two of three HCD strains. Molecular and transcriptomic analyses suggested that two HCD mutants were a result of the gain-of-function phenotype, both linking to the abnormality of mitochondrial functions. Taken together, our results demonstrate that HCD strains can be obtained through continuous subcultures under low illumination conditions.

• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1135-1156
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• 2014

The ratcheting effect greatly challenges the design of piping components. With the assistance of the quasi-three point bending apparatus, ratcheting and the ratcheting boundary of pressurized straight Z2CND18.12N stainless steel pipe under bending loading and vertical displacement control were studied experimentally. The characteristics of progressive inelastic deformation in axial and hoop directions of the Z2CND18.12N stainless steel pipes were investigated. The experiment results show that the ratcheting strain occurs mainly in the hoop direction while there is less ratcheting strain in the axial direction. The characteristics of the bending ratcheting behavior of the pressure pipes were derived and compared under load control and displacement control, respectively. The results show that the cyclic bending loading and the internal pressure affect the ratcheting behavior of the pressurized straight pipe significantly under load control. In the meantime, the ratcheting characteristics are also highly associated with the cyclic displacement and the internal pressure under displacement control. All these factors affect not only the saturation of the ratcheting strain but the ratcheting strain rate. A series of multi-step bending ratcheting experiments were conducted under both control modes. It was found that the hardening effect of Z2CND18.12N stainless steel pipe under previous cyclic loadings no matter with high or low displacement amplitudes is significant, and the prior loading histories greatly retard the ratcheting strain and its rate under subsequent loadings. Finally, the ratcheting boundaries of the pressurized straight Z2CND18.12N stainless steel pipe were determined and compared based on KTA/ASME, RCC-MR and the experimental results.

• Structural Engineering and Mechanics
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• v.68 no.4
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• pp.475-483
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• 2018

Square tubular columns are commonly used in moment resisting frames, while through-diaphragm connection is the most typical configuration detail to connect the H-shaped beam to the column. However, brittle fracture normally occurs at the complete joint penetration weld between the beam flange and the through-diaphragm due to the stress concentration caused by the geometrical discontinuity. Accordingly, three improved types of through-diaphragm are presented in this paper to provide smooth force flow path comparing to that of conventional connections. Tensile tests were conducted on four specimens and the results were analyzed in terms of failure modes, load-displacement response, yield and ultimate capacity, and initial stiffness. Furthermore, strain distributions on the through-diaphragm, the beam flange plate, and the column face were comprehensively evaluated and discussed. It was found that all the proposed three types of improved through-diaphragm connections were able to reduce the stress concentration in the welds between the beam flange and the through-diaphragm. Furthermore, the stress distribution in connection with longer tapered through-diaphragm was more uniform.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.439-449
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• 2017

Beauveria bassiana infects a number of pest species and is known to produce insecticidal substances, such as the nonribosomal peptides (NRPs) beauvericin and bassianolide. However, most NRPs and their biological roles in B. bassiana remain undiscovered. To identify NRPs that potentially contribute to pathogenesis, the 21 predicted NRP synthetases (NRPSs) or NRPS-like proteins of B. bassiana ARSEF 2860 were primarily ranked into three functional groups: basic metabolism (7 NRPSs), pathogenicity (12 NRPSs), and unknown function (2 NRPSs). Based on the transcript levels during in vivo growth on diamondback moth (Plutella xylostella (Linnaeus)), half of the Group II NRPSs were likely to be involved in infection. Given that the metabolites biosynthesized by these NRPSs remain to be determined, our result underlines the importance of the NRPSome in fungal pathogenesis, and will serve as a guide for future genomic mining projects to discover functionally essential and structurally diverse NRPs in fungal genomes.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.637-647
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• 2018

Extra-hypothalamic growth hormone-releasing hormone (GHRH) plays an important role in reproduction. To study the treatment effect of Grin (a novel hGHRH homodimer), the infertility models of 85 male Chinese hamsters were established by intraperitoneally injecting 20 mg/kg of cyclophosphamide once in a week for 5 weeks and the treatment with Grin or human menopausal gonadotropin (hMG) as positive control was evaluated by performing a 3-week mating experiment. 2-8 mg/kg of Grin and 200 U/kg of hMG showed similar effect and different pathological characteristics. Compared to the single cyclophosphamide group (0%), the pregnancy rates (H-, M-, L-Grin 26.7, 30.8, 31.3%, and hMG 31.3%) showed significant difference, but there was no difference between the hMG and Grin groups. The single cyclophosphamide group presented loose tubules with pathologic vacuoles and significant TUNEL positive cells. Grin induced less weight of body or testis, compactly aligned tubules with little intra-lumens, whereas hMG caused more weight of body or testis, enlarging tubules with annular clearance. Grin presented a dose-dependent manner or cell differentiation-dependentincrease in testicular GHRH receptor, and did not impact the levels of blood and testicular GH, testosterone. Grin promotes fertility by proliferating and differentiating primitive cells through up-regulating testicular GHRH receptor without triggering GH secretion, which might solve the etiology of oligoasthenozoospermia.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.181-189
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• 2008

The aim of this study was to evaluate the effects of $Ca^{2+}$, $HCO_3{^-}$ and BSA on the in vitro capacitation-associated protein tyrosine phosphorylation, hyperactivation and acrosome reaction in guinea pig sperm. Caudal epididymal sperm were incubated in four different groups: modified TALP (Tyrode's albumin lactate pyruvate) or TALP without one of the medium constituents ($Ca^{2+}$, $HCO_3{^-}$ and BSA). After incubation for the required time (0 h, 0.5 h, 1 h, 3 h, 5 h, and 7 h), sperm were removed for further experiment. The capacitation effect was assessed by CTC (Chlortetracycline) staining. Western blotting and indirect immunofluorescence were used to analyze the level and localization of tyrosine phosphorylation. The results showed that guinea pig sperm underwent a time-dependent increase in protein tyrosine phosphorylation during the in vitro capacitation and the percentage of protein tyrosine phosphorylated sperm increased from 36% to 92% from the beginning of incubation to 7 h incubation. Also, there was a shift in the site of phosphotyrosine-specific fluorescence from the head of sperm to both the head and the flagellum. Moreover, an absence of $Ca^{2+}$ or $HCO_3{^-}$ inhibited in vitro hyperactivation and acrosome reaction and decreased the phosphorylation of the proteins throughout the period of in vitro capacitation. However, an absence of BSA could not influence these processes if substituted by polyvinyl alcohol (PVA) in the medium.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1440-1446
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• 2011

The study investigated the effects of dietary Vitamin E (VE) on nitric oxide (NO) metabolism, immune function and analyzed the correlation between NO free radical and cytokines (IL-2 and IL-6) in broilers. One hundred and fifty 2-week-old broilers were randomly divided into three groups. Control group and lower VE ($VE^-$) group were provided with a basic diet supplemented with 12.55 mg/kg VE and 2.55 mg/kg VE for 30 days, respectively. Higher VE ($VE^{-}-VE^+$) group was supplemented with 2.55 mg/kg VE in the first 15 days and then 32.55 mg/kg VE in the next 15 days. Five broilers in each group were then sacrificed on the 5th, 10th, 15th, 20th, 25th and 30th days, respectively, and the content of NO free radical, superoxide dismutase (SOD), glutathione peroxidase (GSHPx), malondialdehyde (MDA) and cytokines, IL-2 and IL-6, were measured. The results showed that lower VE could decrease growth performance of broilers while higher VE could increase growth performance and eliminate differences resulted from feeding lower VE dietary in early stages (p<0.05). Compared with the control group, lower VE could increase significantly NO and MDA concentration, and increase IL-2 concentration in serum (p<0.05). Higher VE could significantly increase activities of SOD and glutathione GSH-Px (p<0.05). IL-2 is positively correlated with NO in heart (p<0.05) and IL-6 is negatively correlated with NO in liver (p<0.05) and heart (p<0.01). These results indicate that dietary VE could regulate antioxidant capacity and NO metabolism of broilers and higher VE-supplemented diet could directly decrease production of IL-2.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1465-1470
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• 2014

Inhibitor of DNA binding 1 (Id1) plays an important role in genesis and metastatic progression of prostate cancer. We previously reported that down regulation of Id1 by small interfering RNA could inhibit the proliferation of PC3 cells and growth of its xenografted tumors. Curcumin, the active ingredient of turmeric, has shown anti-cancer properties via modulation of a number of different molecular regulators. Here we investigated whether Id1 might be involved in the anti-cancer effects of curcumin in vivo and in vitro. We firstly confirmed that curcumin inhibited cell viability in a dose-dependent fashion, and induced apoptosis in PC3 cells, associated with significant decrease in the mRNA and protein expression of Id1. Similar effects of curcumin were observed in tumors of the PC3 xenografted mouse model with introperitoneal injection of curcumin once a day for one month. Tumor growth in mice was obviously suppressed by curcumin during the period of 24 to 30 days. Both mRNA and protein levels of Id1 were significantly down-regulated in xenografted tumors. Our findings point to a novel molecular pathway for curcumin anti-cancer effects. Curcumin may be used as an Id1 inhibitor to modulate Id1 expression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4865-4869
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• 2014

Objective: This study evaluated the expression level of high mobility group box-B1 (HMGB-1) and matrix metalloproteinase-9 (MMP-9) in non-small cell lung cancer (NSCLC) inmorder to reveal any relation with development and prognosis. Methods: NSCLC and normal tissues were selected from 30 patients at age of 30-73, and used for RT-PCR and Western blot analyses of HMGB-1. A total of 100 paraffin embedded NSCLC tissues were also isolated from patients through surgical resection, and used for detection of HMGB-1 by immunohistochemistry. In addition, 50 samples were also applied for MMP-9 detection, and 30 normal tissues were considered as controls. Correlation analysis of HMGB-1 and MMP-9 was carried out by Pearsons correlation coefficient. Results: The average expression level of HMGB-1 in NSCLC patients was significantly higher than in normal lung tissues. In addition, patients in III-IV period exhibit significantly higher positive rate of HMGB-1 when compared with I-II period cases. Furthermore, a positive correlation with HMGB-1 was found in the expression of MPP-9. Conclusion: HMGB-1 was highly expressed in NSCLC, which may become a prognostic and predictive marker for NSCLC. Besides, MPP-9 was positively correlated with HMGB-1.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4367-4372
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• 2014

We here document discovery of expression profile of myeloid derived suppressor cells (MDSCs) in chronic hepatitis B (CHB) patients and changes in the course of disease. The study population was composed of 75 outpatient HBV cases and 15 healthy control cases. Peripheral blood samples were collected for separation of mononuclear cells. Levels of MDSCs labeled with Lin-DR-CD11b+CD33+ obtained from peripheral blood mononuclear cells (PBMC), were revealed to have significant differences between the CHB and other groups. They were 0.414% for health control cases and 0.226% for CHB cases (Z=-2.356, p=0.0189). It also observed that the group of HBeAg positive cases had significant difference in MDSCs/PBMC median ($X^2=11.877$, p=0.003), compared with group of HBeAg negative cases and the healthy control group. It suggested considerable MDSCs might be involved in HBeAg immune tolerance. In addition, negative correlations between MDSCs/PBMC and parameters of ALT, AST and TBil, while positive correlation between MDSCs/PBMC and ALB parameter were found. Multiple comparisons between the four phases and health control phase again, there was a statistically sifnificant difference ($X^2=17.198$, p=0.002). Taken together, these findings may provide a new immunotherapy strategy for reduced the expression levels of MDSCs in CHB patients, through induction of an autoimmune response to virus removal.