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The production of therapeutic proteins by mammalian cell culture is complex and sets high requirements for process, facility, and equipment design, as well as rigorous regulatory and quality standards. One particular point of concern and significant risk to supply chain is the susceptibility to contamination such as bacteria, fungi, mycoplasma, and viruses. Several technologies have been developed to create barriers for these agents to enter the process, e.g. filtration, UV inactivation, and temperature inactivation. However, if not implemented during development of the manufacturing process, these types of process changes can have significant impact on process performance if not managed appropriately. This article describes the implementation of the high-temperature short-time (HTST) treatment of cell culture media as an additional safety barrier against adventitious agents during the transfer of a large-scale commercial cell culture manufacturing process. The necessary steps and experiments, as well as subsequent results during qualification runs and routine manufacturing, are shown.  相似文献   
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This study examined the value of blood marker S100A1 in detecting cardiotoxicity induced by chemotherapy agents; trastuzumab and lapatinib, in normal rat heart. The rats were divided into three groups: control (n = 8, no treatment), T (n = 8, one time ip treatment with 10 mg/kg trastuzumab) and L (n = 8, oral treatment with 100 mg/kg/day lapatinib for 7 days). The activities of oxidative stress parameters Malondialdehyde (MDA), Superoxide dismutase (SOD), Catalase (CAT) and Glutathione (GSH) were measured from the extracted cardiac tissues. The levels of troponinI and S100A1 expressions were measured from blood samples. All biomarkers responded to the treatments as they exhibited alterations from their normative values, validating the chemically induced cardiotoxicity. S100A1 expression attenuated significantly (75%), which made the sensitive detection of cardiotoxicity feasible. Assessment of cardiotoxicity with S100A1 may be a valuable alternative in clinical oncology of cancers in some organs such as breast and prostate, as they do not overexpress it to compete against.  相似文献   
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The aim of this study was to investigate structural and biochemical changes in testes of rats treated with the thiosemicarbazone derivative thiazole ring Schiff base, (4-(1-phenyl-methylcyclobutane-3-yl)-2-(2-hydroxybenzylidene-hydrazino) thiazole (L), and its Cd(II) complex (CdL(2)). The animals were divided into three groups. Group I was designated as control. The rats in groups II and III were injected subcutaneously with L or CdL(2) respectively at 150-mg kg(-1) doses at 3-day intervals for 15 days. At the end of the study, blood samples were collected for biochemical analysis, and testes were removed for histological examinations. Serum levels of vitamin A, E and MDA of the L-injected group were similar to the control group. While CdL(2) treatment decreased serum vitamin A and E levels, it increased the MDA level compared to other groups. Histologically, the testes structures of L-treated animals were similar to the control. Spermatogenic cells in seminiferous tubules of CdL(2)-treated animals displayed necrosis. Nuclei of spermatogonia and primary spermatocytes were pyknotic and heterochromatic. Homogenous pink particles were present in place of the spermatids. The interstitial areas were oedematous and intertubular vessels were plugged. In conclusion, the present results indicate that L does not cause biochemical and morphological alterations, but its Cd(II) complex has degenerative effects in normal rat testes.  相似文献   
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The production of extracellular α-amylase by thermotolerant Bacillus subtilis was studied in solid state fermentation (SSF). The effect of wheat bran (WB) and rice husk (RH) was examined. The appropriate incubation period, moisture level, particle size and inoculum concentration was determined. Maximum yields of 159,520 and 21,760 U g−1 were achieved by employing WB and RH as substrates in 0.1 M phosphate buffer at pH 7 with 30% initial moisture content at 24 and 48 h. Particle size and inoculum concentration were found to be 1000 μm, 20% and 500 μm, 15% for WB and RH, respectively. Enzyme yield was 7.3-fold higher with WB medium compared with RH.  相似文献   
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The period of four oscillation of the S state intermediates of the water oxidizing complex in Photosystem II (PSII) is commonly analyzed by the Kok parameters. The important miss factor determines the efficiency for each S transition. Commonly, an equal miss factor has been used in the analysis. We have used EPR signals which probe all S states in the same sample during S cycle advancement. This allows, for the first time, to measure directly the miss parameter for each S state transition. Experiments were performed in PSII membrane preparations from spinach in the presence of electron acceptor at 1 °C and 20 °C. The data show that the miss parameter is different in different transitions and shows different temperature dependence. We found no misses at 1 °C and 10% misses at 20 °C during the S(1)→S(2) transition. The highest miss factor was found in the S(2)→S(3) transition which decreased from 23% to 16% with increasing temperature. For the S(3)→S(0) transition the miss parameter was found to be 7% at 1 °C and decreased to 3% at 20 °C. For the S(0)→S(1) transition the miss parameter was found to be approximately 10% at both temperatures. The contribution from the acceptor side in the form of recombination reactions as well as from the donor side of PSII to the uneven misses is discussed. It is suggested that the different transition efficiency in each S transition partly reflects the chemistry at the CaMn(4)O(5) cluster. That consequently contributes to the uneven misses during S cycle turnover in PSII.  相似文献   
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Whereas retinoid acid (RA) signaling has been implicated in embryonic heart development, its significance in differentiation of specific cardiac subtypes remains largely unknown. In the present study, we took advantage of lineage-specific expression of atrial natriuretic peptide (ANP) in embryonic stem (ES) cells to study RA-induced effects on differentiation of atrial- and pacemaker-like phenotypes. Embryoid bodies (EB) were exposed to 10(-5), 10(-7), and 10(-9) M RA at early (days 1-5 [d1-5]) and late (d6-10) developmental stages, and RA effects on expression of lineage-specific cardiac markers and ion channels were examined. Our initial experiments revealed a detrimental effect of 10(-5) M RA on EB development by inducing marked apoptosis. Morphologic and expression analysis demonstrated that 10(-7) M RA applied at d1-5 was most effective to induce the atrial sublineage. RA did not affect differentiation of pacemaker-like cells, independent of RA concentration and application time. Conversely, RA exposure at an early developmental stage inhibited ventricular-specific MLC-2v gene expression. Late-stage RA administration exhibited no significant alterations in cardiomyogenic differentiation. Terminally differentiated cardiomyocytes exposed to RA at d1-5 or d6-10 displayed unchanged I(Ca,L) and I(to) channel expression compared with untreated cells. However, patch clamp studies revealed a significant increase of I(Ca,L) and I(to) current densities associated with increased levels of the underlying channel subunits in 6-7-day-old cardiomyocytes upon early RA exposure. In contrast, I(f) current density and HCN4 expression remained largely unaffected by RA. Our results imply that RA induces differentiation of ANP-expressing EBs toward an atrial phenotype in a time- and concentration-dependent manner and accelerates expression of I(Ca,L) and I(to) ion channels without affecting differentiation of pacemaker cells.  相似文献   
59.
Eight different agro-residues were tested for α-amylase and protease production by using Bacillus licheniformis ZB-05. Among them, rice husk (RH) was proved as the best substrate for two enzymes (α-amylase 443 U/g and protease 469,000 U/g). Maximum enzyme production was observed to be 30 % initial moisture, with a growth period of 36 h in 20 and 30 % inoculum volumes for α-amylase and protease, respectively. The best enzyme recovery from solid mass was obtained when extracted with tap water. Among the tested various nitrogen sources, 1 % ammonium sulphate followed by 2 % Bacto liver, 2 % ammonium sulphate and 1 % Bacto casaminoacid served as the best inorganic and organic nitrogen sources for α-amylase and protease production, respectively. As additional carbon sources, 2 % soluble starch enhanced α-amylase production, while 1 % maltose enhanced protease production.  相似文献   
60.
The aim of this work was to investigate the enzyme inhibition, antioxidant activity, and phenolic compounds of Lecokia cretica (Lam .) DC. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α‐glycosidase enzymes were strongly inhibited by the L. cretica extracts. IC50 values for the three enzymes were found as 3.21 mg/mL, 2.1 mg/mL, and 2.07 mg/mL, respectively. Antioxidant activities were examined in both aqueous and ethanol (EtOH) extracts using CUPRAC, FRAP, and DPPH method. Also, the phenolic compounds of the endemic plant were identified and quantified by using HPLC/MS/MS. According to the results, the extracts have remarkable antioxidant activities. The most abundant phenolic acids of L. cretica in EtOH extract were determined as quinic acid (12.76 mg/kg of crude extract), chlorogenic acid (3.39 mg/kg), and malic acid (2.38 mg/kg).  相似文献   
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