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Effects of the methanol fraction of modified Seonghyangjeongki-san water extract on transient ischaemic brain injury in mice. PHARMACEUTICAL BIOLOGY 2021; 59:840-853. [PMID: 34184969 PMCID: PMC8245089 DOI: 10.1080/13880209.2021.1941130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 06/04/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
CONTEXT Recently in Korean medicine, the antioxidant and anti-inflammatory activities of Seonghyangjeongki-san (SHJKS) were reported. However, studies on the specific mechanisms of action of SHJKS for the treatment of ischaemic stroke are still lacking. OBJECTIVE This study investigates the mechanism of action of the water extract methanol fraction of modified SHJKS (SHJKSmex) on cerebral ischaemic injury. MATERIALS AND METHODS C57BL/6 male mice were orally administered SHJKSmex (30, 100, or 300 mg/kg) for 3 consecutive days (2 days, 1 day, and 1 h, respectively) before middle cerebral artery occlusion (MCAO). Twenty-four hours after MCAO, the infarct volumes were measured, brain edoema indices were calculated, and neurological deficit scores were determined. Inflammation-related substances in the ipsilateral hemisphere were determined by western blotting, dichlorofluorescin diacetate, thiobarbituric acid-reactive substances assay, and enzyme-linked immunosorbent assay. RESULTS SHJKSmex pre-treatment at 300 mg/kg decreased infarct volume by 87% and mean brain water content by 90% of the MCAO control group. Moreover, SHJKSmex effectively suppressed the expression of inducible nitric oxide synthase, reactive oxygen species, interleukin 1, and caspases-8 and -9 and increased the B-cell lymphoma 2/Bcl-2-associated X protein ratio (Bcl-2/Bax) in ischaemic mouse brain. The hippocampal pyramidal cell densities were significantly increased in the 300 mg/kg SHJKSmex-administered group compared to the MCAO control group. DISCUSSION AND CONCLUSIONS SHJKSmex protected the brain from ischaemic stroke in mice through its antioxidant, anti-inflammatory, and antiapoptotic activities. Our findings suggest that SHJKSmex is a promising therapeutic candidate for the development of a new formulation for ischaemia-induced brain damage.
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Effects of cigarette smoke on Haemophilus influenzae-induced otitis media in a rat model. Sci Rep 2021; 11:19729. [PMID: 34611260 PMCID: PMC8492685 DOI: 10.1038/s41598-021-99367-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/23/2021] [Indexed: 11/09/2022] Open
Abstract
Exposure to cigarette smoke (CS) is a factor that could delay or worsen the recovery of otitis media (OM) by causing inflammatory swelling of the Eustachian tube (ET). However, despite the suggested relationship, little is known about the association between OM and CS. Therefore, we aimed to evaluate the effects of CS on the development, progression, and recovery of OM, as well as the histological and molecular changes caused by CS exposure, by using a rat model of OM infected with non-typeable Haemophilus influenzae (NTHi). Eighty Sprague-Dawley rats with normal middle ears (MEs) were divided into four groups (n = 20 rats/group): control, CS, OM, and CS + OM. The CS and CS + OM groups were exposed to CS for 2 weeks. The inflammatory reaction to NTHi was more intense and lasted longer in the CS + OM group than in the other groups. Goblet cell proliferation and mucus secretion in the ET were more significant in the CS and CS + OM groups than in the other groups. These findings suggested that because CS directly affects the ET and ME mucosa, bacterial OM can become more severe and may resolve more slowly in the presence of CS exposure rather than in its absence.
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Beekeeping Genetic Resources and Retrieval of Honey Bee Apis mellifera L. Stock in the Russian Federation: A Review. INSECTS 2021; 12:684. [PMID: 34442250 PMCID: PMC8396492 DOI: 10.3390/insects12080684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 12/02/2022]
Abstract
The loss of honey bees has drawn a large amount of attention in various countries. Therefore, the development of efficient methods for recovering honey bee populations has been a priority for beekeepers. Here we present an extended literature review and report on personal communications relating to the characterization of the local and bred stock of honey bees in the Russian Federation. New types have been bred from local colonies (A. mellifera L., A. m. carpatica Avet., A. m. caucasia Gorb.). The main selection traits consist of a strong ability for overwintering, disease resistance and different aptitudes for nectar collection in low and high blooming seasons. These honey bees were certified by several methods: behavioral, morphometric and genetic analysis. We illustrate the practical experience of scientists, beekeepers and breeders in breeding A. mellifera Far East honey bees with Varroa and tracheal mite resistance, which were the initial reasons for breeding the A. mellifera Far Eastern breed by Russian breeders, Russian honey bee in America, the hybrid honey bee in Canada by American breeders, and in China by Chinese beekeepers. The recent achievements of Russian beekeepers may lead to the recovery of beekeeping areas suffering from crossbreeding and losses of honey bee colonies.
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Prognostic implication of elevated cardiac troponin I in patients visiting emergency department without diagnosis of coronary artery disease. Clin Chem Lab Med 2021; 59:1107-1113. [PMID: 33554539 DOI: 10.1515/cclm-2020-1392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/22/2020] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Elevated cardiac troponin is not uncommon in patients visiting emergency department (ED) even without coronary artery disease, but its prognostic implication is not well understood in such patients. METHODS In this retrospective single-center registry, we investigated clinical outcome of patients visiting ED without documented coronary artery disease. Patients were categorized according to the maximal value of Siemens ADVIA Centaur TnI-Ultra assay (TnI) within 24 h after visit. Primary endpoint was 180-day all-cause death that included cardiac and non-cardiac death. RESULTS A total of 35,205 patients with median age 61 years and male gender 54.7% were included. Below the lowest level of detection (LOD) (≤0.006 ng/mL), between LOD and assay-specific <99th percentile (0.007-0.039 ng/mL), below median of ≥99th percentile (0.040-0.149 ng/mL), and above median of ≥99th percentile (≥0.150 ng/mL) TnI were found in 18,502 (52.6%), 11,338 (32.2%), 3,029 (8.6%), and 2,336 (6.6%) patients. In the 180-day follow-up period, 4,341 (12.3%) all-cause death including 694 (2.0%) cardiovascular death and 3,647 (10.4%) non-cardiovascular death developed. The risks of all-cause, cardiovascular, and non-cardiovascular death increased across higher TnI strata (hazard ratio [HR]=1.3 to 2.4; 2.0 to 9.3; 1.3 to 1.7; p<0.001, all). Analyses of multivariate models showed consistent results. CONCLUSIONS In patients visiting ED, elevated TnI was associated with higher risk of 180-day cardiovascular and non-cardiovascular death. Patients with elevated TnI may need additional evaluation or careful follow-up even without primary diagnosis of coronary artery disease.
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Pregnenolone as a potential candidate for hormone therapy for female reproductive disorders targeting ERβ. Mol Reprod Dev 2018; 86:109-117. [PMID: 30411422 DOI: 10.1002/mrd.23086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 11/06/2018] [Indexed: 12/12/2022]
Abstract
Many steroid hormones such as estrogen (E2) bind to their receptors for the regulation of biological processes. Pregnenolone (P5) is the precursor form of almost all steroid hormones and is often used to treat skin disorders and neurological complications. However, the mechanism and physiological function of P5 in reproductive organs are not well established. In this study, we investigated the effects of P5 on activation and expression of E2 receptor (ER) in the uteri and ovaries. To study the mechanism of P5 directly, Ishikawa cells were transfected with E2 response element (ERE)-luciferase plasmid and isoforms of ER. ERE-luciferase activity induced by P5 was similar to that induced by E2, and P5 showed high activity for ERβ without any relevance to P5-metabolizing hormones such as progesterone (P4) and E2. In an animal study, immature female rats treated with P5 showed upregulation of ERα and downregulation of ERβ in the uteri, which is the main organ expressing ERα. In ERβ-expressing organ ovaries, estrogen receptor 1, estrogen receptor 2, and P4 receptor were all downregulated by P5 and E2. Also, a decrease of ovarian cell proliferation and viability was observed in response to P5 relative to the control, suggesting that P5 may be a candidate for antiproliferative hormone of ovarian cancer. These findings suggest that P5 stimulates ERE promoter by ERβ-mediated signaling in the uteri and ovaries. Activation of ERβ by P5 may help in understanding the mechanism of ER-related female reproductive diseases such as endometriosis and ovarian cancer.
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Epigenetically altered miR-1247 functions as a tumor suppressor in pancreatic cancer. Oncotarget 2018; 8:26600-26612. [PMID: 28460450 PMCID: PMC5432282 DOI: 10.18632/oncotarget.15722] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/13/2017] [Indexed: 01/06/2023] Open
Abstract
Altered expression of microRNAs has been strongly implicated in human cancers, and growing evidence is emerging that a number of miRNAs are downregulated in cancer associated with CpG island hypermethylation. Although pancreatic cancer is one of the most malignant human cancers, the roles of miRNAs underlying the tumorigenesis of pancreatic cancer are still poorly understood. In the present study, we explored the molecular functional role of microRNA-1247 as tumor suppressor associated with epigenetic alteration in pancreatic cancer. CpG islands methylation of miR-1247 is frequently observed in various pancreatic cancer cell lines and in primary pancreatic tumors, but not in normal pancreatic tissue. Ectopic expression of miR-1247 in five pancreatic cancer cell lines results in suppressing of cell growth, proliferation, migration, and invasion in vitro and tumorigenicity of pancreatic cancer cells in vivo. Interestingly, we found one putative target gene of miR-1247, regulator of chromosome condensation 2 (RCC2), harbored miR-1247 target sequences in the 3′ UTR of its mRNA. In functional studies in vitro to understand the interaction between miR-1247 and RCC2, decreasing of RCC2 gene expression by miR-1247 was observed by immunoblotting and immunohistochemistry at both mRNA and protein levels. Moreover, luciferase reporter assay confirmed that RCC2 was a direct target of miR-1247. Taken together, our data suggest that CpG island hypermethylation of miR-1247 is responsible for its downregulation in pancreatic cancer, and ectopic expression of miR-1247 functions as a potential tumor suppressor targeting RCC2 in pancreatic cancer cells.
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Combinatorial effects of an epigenetic inhibitor and ionizing radiation contribute to targeted elimination of pancreatic cancer stem cell. Oncotarget 2017; 8:89005-89020. [PMID: 29179494 PMCID: PMC5687664 DOI: 10.18632/oncotarget.21642] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/27/2017] [Indexed: 01/03/2023] Open
Abstract
Pancreatic cancer is associated with a high mortality rate, owing to de novo and acquired drug resistance, thereby leading to highly invasive and metastatic pancreatic cancer cells. Therefore, targeting pancreatic cancer stem cells (CSCs) may be a novel therapeutic strategy for the treatment of pancreatic cancer. Here, we combined a DNA methylation inhibitor (5-aza-2'-deoxycytidine; 5-aza-dC) and ionizing radiation (IR) to improve anti-cancer effects by inhibiting growth and proliferation and promoting apoptosis of pancreatic cancer cells in vitro and in vivo. Importantly, the combinatorial effect of 5-aza-dC with IR on sphere-forming pancreatic cancer cells was preferentially targeted toward CSCs through the downregulation of regulatory factors of self-renewal and CSC surface markers. We next performed the RNA sequencing to understand the underlying cellular mechanisms of the combined treatment with IR and 5-aza-dC in pancreatic cancer cells. Global transcriptome profiling indicated that the expression of the Oct4-centered transcriptional network of genes was significantly downregulated in cells with combination treatment. Our data suggested that combination treatment with DNA methylation inhibitor and IR may be a novel therapeutic strategy for pancreatic cancer. Overall, these findings support the use of epigenetic therapy in combination with radiotherapy to improve therapeutic efficacy by targeting and eradicating pancreatic CSCs.
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Abstract LB-227: Combined treatment with radiation and epigenetic regulation improve to targeting cancer stem cells in pancreatic cancer. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-lb-227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Increasing evidences suggests that various cancer types contain a population of cells that display stem cell properties. These cells are called cancer stem cells (CSCs). They are virtually resistant to radiation, and may contribute to treatment resistance and recurrence. Therefore, therapies specifically targeting CSCs will likely be needed for complete tumor eradication. Exposure of cells to ionizing radiation (IR) induces, not only, activation of multiple signaling pathways that play critical roles in cell fate determination, but also alteration of molecular pathways involved in cell death or survival. Recently, DNA methylation has been established as a critical epigenetic process involved in the regulation of gene expression in cancer cells, suggesting that DNA methylation inhibition may be an effective cancer treatment strategy. We therefore investigated the combination effect of a DNA methyltransferase inhibitor, 5-aza-2’-deoxycytidine (5-aza-dC), and radiation treatment in pancreatic cancer. Pancreatic cancer cell lines were initially tested for radiation sensitivity by ionizing radiation (IR) in vitro and were treated with 5-aza-dC. The effects of 5-aza-dC along with irradiation on cell growth, cell cycle distribution, apoptosis, and apoptosis-related gene expression were examined. Combination irradiation treatment with 5-aza-dC significantly decreased growth activity compared with irradiation or 5-aza-dC treatment alone. To understand whether combination treatment can target to pancreatic cancer stem cells, we observed that combination treatment can significantly reduce Oct4, Nanog, Sox2, CD133, and CD44 levels which are key factors for self-renewal pathway or cancer stem cell surface markers in pancreatic cancer cells, respectively. Using transcriptome analysis, OCT4 target genes showed differential expression pattern between irradiation or 5-aza-dC treatment alone and combination treatment. In addition, sphere forming assay supports these data in vitro and in vivo, describing that combination effect of IR and 5-aza-dC can reduce significantly sphere forming ability and proportion of side population (putative CSCs) significantly decreased in combination treated cells compared to control or single treatment. Therefore combined treatment of IR and 5-aza-dC is capable of eliminating pancreatic CSCs. Further investigation of this useful approach may lead to the development of a novel intervention for the cancer therapeutic strategy.
Citation Format: Joo Mi Yi, Hyun-Mi Kwon, Eun-Jin Kang, Kwangmo Yang. Combined treatment with radiation and epigenetic regulation improve to targeting cancer stem cells in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-227. doi:10.1158/1538-7445.AM2017-LB-227
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Pregnenolone sulfate regulates prolactin production in the rat pituitary. J Endocrinol 2016; 230:339-46. [PMID: 27507676 DOI: 10.1530/joe-16-0088] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 11/08/2022]
Abstract
Pregnenolone sulfate (PS) is a neuroactive steroid hormone produced in the brain. In this study, the effects of PS on synthesis and secretion of rat pituitary prolactin (PRL) were examined. To accomplish this, GH3 rat pituitary adenoma cells were treated with PS, which showed significantly increased mRNA and protein levels of PRL compared with the control. The mechanism of action responsible for the effects of PS on PRL synthesis and secretion was investigated by pretreating cells with inhibitors of traditional PRL- or the PS-related signaling pathway. PS-stimulated PRL transcription was significantly reduced by inhibitors of PKA, PKC and MAPK, but unchanged by GABAAR and NMDAR inhibitors. Western blotting analysis revealed that the total ERK1/2 level was upregulated in a time-dependent manner following PS treatment. An approximate 10% increase in GH3 cell proliferation was also observed in response to PS relative to the control. In the animal study, levels of PRL in the pituitary and in serum were elevated by PS. PS-stimulated PRL synthesis was also found to be associated with decreased expression of PRL target genes such as GNRH1, FSHB and LHB. These findings show that PS upregulates PRL synthesis and secretion in vivo and in vitro via MAPK signaling, suggesting that it has the potential for use as a therapeutic hormone to treat PRL-related disorders such as hypoprolactinemia and low milk supply.
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The effects of vitamin D3 on lipogenesis in the liver and adipose tissue of pregnant rats. Int J Mol Med 2015; 36:1151-8. [PMID: 26239543 DOI: 10.3892/ijmm.2015.2300] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/15/2015] [Indexed: 11/06/2022] Open
Abstract
Obesity is a worldwide individual and public health issue, and contributes to the development of numerous chronic diseases. In particular, maternal obesity has harmful effects on both the mother and child during and after pregnancy. The digestion and metabolism of food are controlled by endocrine factors, including insulin, glucagon and estrogen. These hormonal factors are differentially regulated during pregnancy due to the specialized hormonal environment during this period. In the present study, we examined the effects of 1,25-dihydroxyvitamin D3 (VD3), an active hormonal form of nutritional vitamin D3, on lipid metabolism in pregnant rats. The body weight of rats treated with VD3 was significantly reduced compared to that of the rats in the control group. In addition, histological analysis demonstrated that the amount of fat stored in adipocytes was reduced by treatment with VD3. To determine the role of VD3 in lipid metabolism, the expression levels of lipid metabolism‑associated genes were measured in the rat adipose tissue and liver. VD3 negatively regulated the expression of various lipogenic genes, including fatty acid synthase (FAS), stearoyl-CoA desaturase 1 (SCD1) and acetyl-CoA carboxylase 1 (ACC1), in both the adipose tissue and liver. However, the regulators of lipogenic enzymes such as, sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor-γ (PPAR-γ) and insulin-induced gene 2 (INSIG2) were differentially regulated by VD3 in a tissue‑specific manner. On the whole, these findings suggest that VD3 regulates lipid metabolism and deposition in the liver and adipose tissue, and thereby reduces fat in pregnant animals, as well as body weight. Our results suggest that the alteration of lipogenesis through the administration of VD3 may help to reduce excessive weight gain during pregnancy and prevent obesity‑related pregnancy complications such as pre-eclampsia, gestational diabetes, hypertension and issues with labor.
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The adverse effect of 4-tert-octylphenol on fat metabolism in pregnant rats via regulation of lipogenic proteins. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2015; 40:284-291. [PMID: 26164745 DOI: 10.1016/j.etap.2015.06.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/14/2015] [Accepted: 06/19/2015] [Indexed: 06/04/2023]
Abstract
Alkylphenols such as 4-tert-octylphenol (OP), nonylphenol, and bisphenol A are classified as endocrine-disrupting chemicals (EDCs). Digestion and metabolism of food are controlled by many endocrine factors, including insulin, glucagon, and estrogen. These factors are differentially regulated during pregnancy. The alteration of nutritional intake and fat metabolism may affect the maintenance of pregnancy and supplementation of nutrients to the fetus, and therefore can cause severe metabolic diseases such as ketosis, marasmus and diabetes mellitus in pregnant individuals. In this study, we examined the effects of OP on fat metabolism in pregnant rats. Ethinyl estradiol (EE) was also administered as an estrogenic positive control. In our results, rats treated with OP showed significantly reduced body weights compared to the control group. In addition, histological analysis showed that the amount of fat deposited in adipocytes was reduced by OP treatment. To study the mechanism of action of OP in fat metabolism, we examined the expression levels of fat metabolism-associated genes in rat adipose tissue and liver by real-time PCR. OP and EE negatively regulated the expression of lipogenic enzymes, including FAS (fatty acid synthase), ACC-1 (acetyl-CoA carboxylase-1), and SCD-1 (stearoyl-CoA desaturase-1). The levels of lipogenic enzyme-associated transcription factors such as C/EBP-α (CAAT enhancer binding protein alpha) and SREBP-1c (sterol regulatory element binding protein-1c) were also reduced in both liver and adipose tissue. In summary, these findings suggest that OP has adverse effects on fat metabolism in pregnant rats and inhibits fat deposition via regulating lipogenic genes in the liver and adipose tissue. The altered fat metabolism by OP may affect the nutrition balance during pregnancy and can cause metabolism-related diseases.
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Usefulness of serum leucine-rich alpha-2 glycoprotein as a disease activity biomarker in patients with rheumatoid arthritis. J Korean Med Sci 2014; 29:1199-204. [PMID: 25246736 PMCID: PMC4168171 DOI: 10.3346/jkms.2014.29.9.1199] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 05/28/2014] [Indexed: 12/12/2022] Open
Abstract
Our study aimed to investigate whether serum leucine-rich alpha-2-glycoprotein (LRG) levels are elevated in patients with rheumatoid arthritis (RA). In addition, we assessed their correlation with disease activity parameters and pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α). Our study included 69 patients with RA and 48 age- and sex-matched healthy controls. Serum concentrations of TNF-α and LRG were determined by enzyme-linked immunosorbent assay. Serum LRG concentrations were significantly elevated in patients with RA compared with those in healthy controls (30.8 ± 14.4 vs. 22.2 ± 6.1 ng/mL; P<0.001). In patients with RA, serum LRG levels were found to be correlated with disease activity score 28 (DAS28), erythrocyte sedimentation rate, and C-reactive protein levels (γ=0.671; γ=0.612; and γ=0.601, P<0.001, respectively), but not with serum TNF-α levels. Serum LRG levels in patients with an active disease status (DAS28≥2.6) were significantly higher than those in remission (DAS28<2.6) (36.45 ± 14.36 vs. 24.63 ± 8.81 ng/mL; P<0.001). Our findings suggest that serum LRG could contribute to the inflammatory process independent of TNF-α and it may be a novel biomarker for assessing inflammatory activity in patients with RA.
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Association of aldehyde dehydrogenase 1 expression and biologically aggressive features in breast cancer. Neoplasma 2014; 61:352-62. [PMID: 24824938 DOI: 10.4149/neo_2014_045] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
UNLABELLED Aldehyde dehydrogenase 1 (ALDH1) has been regarded as a breast cancer stem cell marker. Several studies have reported that ALDH1 expression is associated with poor prognosis in breast cancer. We aimed, therefore, to determine the prognostic value of ALDH1 expression and its association with several biomarkers in breast cancer tissue using immunohistochemistry. Furthermore, we investigated the characteristics of and differences between cellular and stromal expression of ALDH1. We performed tissue microarray (TMA) analysis of 425 breast cancer tissue samples collected during surgery. Immunohistochemical staining was then performed to measure the expression of ALDH1 and other breast cancer biomarkers. Statistical analysis of the relationship between ALDH1 expression and clinicopathologic characteristics was performed for 390 TMA samples. We found that ALDH1 was expressed in 71 cases (18.2%) in the tumor cells and/or stroma. Of these cases, 38 (9.7%) showed ALDH1 expression in tumor cells and 38 (9.7%) showed ALDH1 expression in the stroma. ALDH1 expression was significantly associated with markers of a poor prognosis, such as young age, estrogen receptor negativity, progesterone receptor negativity, a high histological grade, and a high Ki-67 index. However, ALDH1 expression was not associated with p53, transforming growth factor-beta, Gli-1, YKL-40, or sonic hedgehog expression status. With regard to the expression site, the clinical characteristics did not differ between cases of cellular expression and those of stromal expression. However, ALDH1 expression in tumor cells was correlated with hormone receptor status, histological grade, molecular subtype, epidermal growth factor receptor expression status, and cytokeratin 5/6 expression status while stromal expression of ALDH1 was only correlated with hormone receptor status. Overall, these findings suggest that ALDH1 expression in tumor tissue is associated with a biologically aggressive phenotype. KEYWORDS ALDH1, biologically aggressive, breast cancer.
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Plasma chemerin levels in rheumatoid arthritis are correlated with disease activity rather than obesity. Joint Bone Spine 2013; 81:189-90. [PMID: 23932723 DOI: 10.1016/j.jbspin.2013.07.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 07/16/2013] [Indexed: 11/26/2022]
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Transcription factor Sox4 is required for PUMA-mediated apoptosis induced by histone deacetylase inhibitor, TSA. Biochem Biophys Res Commun 2013; 438:445-51. [DOI: 10.1016/j.bbrc.2013.07.099] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 07/24/2013] [Indexed: 12/25/2022]
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Blood-brain barrier opening to large molecules does not imply blood-brain barrier opening to small ions. Neurobiol Dis 2013; 52:204-18. [PMID: 23291193 DOI: 10.1016/j.nbd.2012.12.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 11/10/2012] [Accepted: 12/20/2012] [Indexed: 10/27/2022] Open
Abstract
Neuroimaging of exogenous tracer extravasation has become the technique of choice in preclinical and clinical studies of blood-brain barrier permeability. Such tracers have a larger molecular weight than small ions, neurotransmitters and many drugs. Therefore, it is assumed that tracer extravasation indicates both permeability to these and the cancelation of the electrical polarization across the barrier. Electrophysiological anomalies following intracarotideal administration of dehydrocholate, a bile salt causing extravasation of the albumin-binding tracer Evans blue, seemingly supported this. By contrast, electron microscopic studies suggested a different hierarchical pattern of blood-brain barrier dysfunction, a milder degree of impairment being characterized by increased function of the transcellular pathway and a severe degree by opening of the tight junctions. This would imply that the extravasation of macromolecules can occur before disruption of the electrical barrier. However, functional evidence for this has been lacking. Here, we further investigated the electrophysiological anomalies following intracarotideal application of dehydrocholate in rats and found that it caused focal cerebral ischemia by middle cerebral artery thrombosis, the electrophysiological recordings being characteristic of long-lasting spreading depolarization. These observations indicated that intracarotideal dehydrocholate is not a suitable model to study the isolated dysfunction of the blood-brain barrier. Second, we studied the topical application of dehydrocholate to the brain and the application of mannitol into the carotid artery. In both models, we found significant extravasation of Evans blue but no changes in either extracellular potassium or the CO(2)-dependent intracortical direct current deflection. The latter is assumed to depend on the proton gradient across the barrier in rats which we confirmed in additional experiments in vivo and in vitro. The stability of the extracellular potassium concentration and the CO(2)-dependent direct current deflection are two functional tests which indicate the integrity of the electrical barrier. Hence, our results provide functional evidence that the blood-brain barrier opening to large molecules does not necessarily imply the opening to small ions consistent with the hierarchy of damage in the previous electron microscopic studies.
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Control Efficacy of Natural Enemies on Four Arthropod Pests found in Greenhouse Hot Pepper. ACTA ACUST UNITED AC 2012. [DOI: 10.5656/ksae.2012.02.1.73] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Streptococcus dysgalactiae subspecies dysgalactiae infection after total knee arthroplasty: a case report. Knee Surg Relat Res 2012; 24:120-3. [PMID: 22708114 PMCID: PMC3373999 DOI: 10.5792/ksrr.2012.24.2.120] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 11/06/2011] [Accepted: 12/04/2011] [Indexed: 10/28/2022] Open
Abstract
Streptococcus dysgalactiae subspecies dysgalactiae (SDSD), Lancefield group C streptococcus, is an animal pathogen which often causes pyogenic infection in domestic animals. Human infection by SDSD has been reported as a cellulitis on the upper arm, but a prosthetic joint infection caused by SDSD after total knee arthroplasty (TKA) has not yet been reported in the literature demonstrating that its clinical manifestation and management have not been well established. In this case report, we aimed to present a case of SDSD prosthetic joint infection after TKA, which was successfully treated by two-stage re-implantation with an application of antibiotic-impregnated cement spacer.
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Levels of plasma-soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) are correlated with disease activity in rheumatoid arthritis. J Rheumatol 2012; 39:933-8. [PMID: 22422501 DOI: 10.3899/jrheum.111218] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To determine whether levels of plasma-soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) are elevated in patients with rheumatoid arthritis (RA) and whether levels are correlated with disease activity and other variables. METHODS Our study included 71 patients with RA and 50 age- and sex-matched healthy controls. Clinical characteristics and laboratory measures, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and 28-joint Disease Activity Score (DAS28) were assessed. Plasma levels of sTREM-1 and tumor necrosis factor-α (TNF-α) were measured by ELISA. RESULTS Patients with RA had significantly higher plasma sTREM-1 levels than healthy controls (170.10 ± 84.71 pg/ml vs 97.41 ± 40.64 pg/ml; p < 0.001). In patients with RA, plasma sTREM-1 levels were found to be correlated with DAS28, ESR, CRP, white blood cell counts, neutrophil counts, and plasma TNF-α levels (r = 0.329, p = 0.005; r = 0.241, p = 0.043; r = 0.314, p < 0.001; r = 0.261, p = 0.028; r = 0.278, p = 0.019; and r = 0.313, p = 0.009, respectively). Plasma sTREM-1 levels in patients with active disease status (DAS28 > 3.2) were significantly higher than in those with low disease status (DAS28 ≤ 3.2; 208.89 ± 100.14 pg/ml vs 150.29 ± 68.70 pg/ml; p = 0.005). CONCLUSION Patients with RA had higher plasma sTREM-1 levels than healthy controls, and plasma sTREM-1 levels were correlated with disease activity measures, suggesting that plasma sTREM-1 could play a role in the inflammatory process associated with TNF-α, and that it may be a useful disease activity marker in RA.
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New molecular bridge between RelA/p65 and NF-κB target genes via histone acetyltransferase TIP60 cofactor. J Biol Chem 2012; 287:7780-91. [PMID: 22249179 DOI: 10.1074/jbc.m111.278465] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nuclear factor-κB (NF-κB) family is involved in the expressions of numerous genes, in development, apoptosis, inflammatory responses, and oncogenesis. In this study we identified four NF-κB target genes that are modulated by TIP60. We also found that TIP60 interacts with the NF-κB RelA/p65 subunit and increases its transcriptional activity through protein-protein interaction. Although TIP60 binds with RelA/p65 using its histone acetyltransferase domain, TIP60 does not directly acetylate RelA/p65. However, TIP60 maintained acetylated Lys-310 RelA/p65 levels in the TNF-α-dependent NF-κB signaling pathway. In chromatin immunoprecipitation assay, TIP60 was primarily recruited to the IL-6, IL-8, C-IAP1, and XIAP promoters in TNF-α stimulation followed by acetylation of histones H3 and H4. Chromatin remodeling by TIP60 involved the sequential recruitment of acetyl-Lys-310 RelA/p65 to its target gene promoters. Furthermore, we showed that up-regulated TIP60 expression was correlated with acetyl-Lys-310 RelA/p65 expressions in hepatocarcinoma tissues. Taken together these results suggest that TIP60 is involved in the NF-κB pathway through protein interaction with RelA/p65 and that it modulates the transcriptional activity of RelA/p65 in NF-κB-dependent gene expression.
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Tip60 regulates myoblast differentiation by enhancing the transcriptional activity of MyoD via their physical interactions. FEBS J 2011; 278:4394-404. [PMID: 21936881 DOI: 10.1111/j.1742-4658.2011.08362.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The progression of muscle differentiation is tightly controlled by multiple groups of transcription factors and transcriptional coregulators. MyoD is a transcription factor of the myogenic basic helix-loop-helix family required for the process of muscle cell differentiation. We now show that Tip60 is required for myoblast differentiation via enhancement of the transcriptional activity of MyoD. Knockdown of Tip60 in C2C12 cells leads to a lack of ability to switch from proliferating myoblasts to differentiated myotubes. Ectopic expression of Tip60 increased MyoD-mediated luciferase activity on the myogenic regulatory gene, myogenin. We also found that Tip60 physically interacts with MyoD using its chromo- and Zn-finger-containing region, and that these protein interactions were required for the effective transcriptional activation of MyoD. Furthermore, a chromatin immunoprecipitation assay revealed that Tip60 recruits MyoD on the myogenin promoter, and Tip60 also increases the levels of acetylated histones H3 and H4 during myogenic differentiation. Taken together, these findings suggest that Tip60 is an important co-activator for MyoD-mediated myogenesis in mouse myoblast C2C12 cells.
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Gelsolin negatively regulates the activity of tumor suppressor p53 through their physical interaction in hepatocarcinoma HepG2 cells. Biochem Biophys Res Commun 2011; 412:44-9. [PMID: 21801713 DOI: 10.1016/j.bbrc.2011.07.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 07/08/2011] [Indexed: 10/18/2022]
Abstract
As a transcription factor, p53 modulates several cellular responses including cell-cycle control, apoptosis, and differentiation. In this study, we have shown that an actin regulatory protein, gelsolin (GSN), can physically interact with p53. The nuclear localization of p53 is inhibited by GSN overexpression in hepatocarcinoma HepG2 cells. Additionally, we demonstrate that GSN negatively regulates p53-dependent transcriptional activity of a reporter construct, driven by the p21-promoter. Furthermore, p53-mediated apoptosis was repressed in GSN-transfected HepG2 cells. Taken together, these results suggest that GSN binds to p53 and this interaction leads to the inhibition of p53-induced apoptosis by anchoring of p53 in the cytoplasm in HepG2 cells.
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Seasonal Occurrence, Development and Preference of Riptortus pedestris on Hairy Vetch. ACTA ACUST UNITED AC 2011. [DOI: 10.5656/ksae.2011.03.0.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Hounsfield units upon PET/CT are useful in evaluating metastatic regional lymph nodes in patients with oesophageal squamous cell carcinoma. Br J Radiol 2011; 85:606-12. [PMID: 21304006 DOI: 10.1259/bjr/73516936] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES This study evaluated the usefulness of measurements of X-ray attenuation (in Hounsfield units) obtained from unenhanced CT images for attenuation correction of the positron emission tomography (PET) data from PET/CT in the assessment of regional lymph node metastasis in oesophageal squamous cell carcinoma. METHODS 17 patients with oesophageal squamous cell carcinoma underwent surgery after evaluation with PET/CT. After the excised lymph nodes were reviewed, we compared the histopathology and PET/CT findings, and analysed the lymph node metastasis. When 18-F fludeoxyglucose (FDG) uptake in the lymph nodes was focally prominent in comparison with background mediastinal activity (regardless of lymph node size), the lymph nodes were considered to be positive for malignancy by PET/CT. The mean Hounsfield units of mediastinal lymph nodes showing abnormally increased FDG uptake in PET/CT was retrospectively evaluated using images from the unenhanced CT component of PET/CT. Receiver operating characteristic (ROC) curve analysis was applied to determine the optimal cut-off value of mean Hounsfield units for detecting individual lymph node metastases. RESULTS For depiction of malignant nodal groups in each lymph node group, the sensitivity, specificity and accuracy of PET/CT based on increased FDG uptake were 58.8%, 74.5% and 70.8%, respectively. For patients with nodal groups that were positive for uptake by PET/CT, the mean attenuation in lymph nodes as measured by CT was 48 ± 13 HU for malignant nodes and 75 ± 18 HU for benign nodes. This difference was statistically significant (p<0.001). Using ROC curve analysis, we determined the cut-off as 71 HU. When we excluded lymph nodes with attenuation higher than 71 HU from the nodes determined as malignant by PET/CT, the specificity and accuracy for detecting metastatic lymph nodes improved to 90.9% and 83.3%, respectively. CONCLUSIONS When interpreting lymph node metastasis in oesophageal squamous cell carcinoma using PET/CT, the assumption that any lymph node with mean HU>71 is benign can improve diagnostic accuracy.
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A Case of Henoch-Schönlein Purpura Complicated by Acute Pancreatitis and Interstitial Pneumonitis. JOURNAL OF RHEUMATIC DISEASES 2011. [DOI: 10.4078/jrd.2011.18.4.292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Neural retina leucine-zipper regulates the expression of Ppp2r5c, the regulatory subunit of protein phosphatase 2A, in photoreceptor development. FEBS J 2010; 277:5051-60. [DOI: 10.1111/j.1742-4658.2010.07910.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Influence of epidermal growth factor supplementation during in vitro maturation on nuclear status and gene expression of canine oocytes. Res Vet Sci 2010; 91:439-45. [PMID: 20888022 DOI: 10.1016/j.rvsc.2010.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 07/20/2010] [Accepted: 09/04/2010] [Indexed: 10/19/2022]
Abstract
This study evaluated the effect of epidermal growth factor (EGF) supplementation during in vitro maturation on the meiotic status and the expression of EGF receptor (EGFr), luteinizing hormone receptor (LHr) and gap junction protein α 5 (GJA5) in canine cumulus-oocyte-complexes (COCs). COCs of ≥110 μm diameter, exhibiting dark pigmentation and completely surrounded by three or more layers of cumulus cells collected from anestrus stage ovaries in natural cycle were matured in TCM-199 supplemented with 10% fetal bovine serum, 0.57 mM cysteine, 10 μg/ml LH and FSH, and different concentrations of EGF (0, 10 and 30 ng/ml). Oocytes cultured for 72 h were fixed to assess the nuclear maturation. Expression of EGFr, LHr and GAJ5 was assessed by immunocytochemistry and real-time PCR. Proportion of metaphase II status of oocytes cultured in in vitro maturation (IVM) medium supplemented with 10 ng/ml EGF for 72 h was significantly (P<0.05) higher than 0 and 30 ng/ml EGF supplemented IVM medium (9.8% vs. 6.5% and 5.2%). In both cumulus cells and oocytes, EGFr protein was undetectable, LHr protein level of expression was low and a strong expression of GJA5 protein was observed. The relative abundance (RA) of EGFr transcript revealed low levels and the LHr expression decreased steadily with addition of EGF. However it did not vary among different concentrations of EGF supplementation. The RA of GJA5 transcript exhibited lower level at 10 ng/ml EGF supplementation. In conclusion, the supplementation of 10 ng/ml EGF in IVM media exerted a positive influence on the progression of maturation to MII phase and the expression level of GJA5 at 72 h, but did not demonstrate any stimulatory role on the expression of EGFr and LHr during the maturation of the canine IVM oocytes.
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Abstract
Accumulation of β-amyloid protein (Aβ) is one of the most important pathological features of Alzheimer's disease. Although Aβ induces neurodegeneration in the cortex and hippocampus through several molecular mechanisms, few studies have evaluated the modulation of transcription factors during Aβ-induced neurotoxicity. Therefore, in this study, we investigated the transcriptional activity of transcription factor CP2 in neuronal damage mediated by Aβ (Aβ(1-42) and Aβ(25-35) ). An unbiased motif search of the transferrin promoter region showed that CP2 binds to the transferrin promoter, an iron-regulating protein, and regulates transferrin transcription. Ectopic expression of CP2 led to increased transferrin expression at both the mRNA and protein levels, whereas knockdown of CP2 down-regulated transferrin mRNA and protein expression. Moreover, CP2 trans-activated transcription of a transferrin reporter gene. An electrophoretic mobility shift assay and a chromatin immunoprecipitation assay showed that CP2 binds to the transferrin promoter region. Furthermore, the binding affinity of CP2 to the transferrin promoter was regulated by Aβ, as Aβ (Aβ(1-42) and Aβ(25-35) ) markedly increased the binding affinity of CP2 for the transferrin promoter. Taken together, these results suggest that CP2 contributes to the pathogenesis of Alzheimer's disease by inducing transferrin expression via up-regulating its transcription.
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The effect of bleaching agent on the flavor of liquid whey and whey protein concentrate. J Dairy Sci 2010; 92:5917-27. [PMID: 19923595 DOI: 10.3168/jds.2009-2535] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The increasing use and demand for whey protein as an ingredient requires a bland-tasting, neutral-colored final product. The bleaching of colored Cheddar whey is necessary to achieve this goal. Currently, hydrogen peroxide (HP) and benzoyl peroxide (BPO) are utilized for bleaching liquid whey before spray drying. There is no current information on the effect of the bleaching process on the flavor of spray-dried whey protein concentrate (WPC). The objective of this study was to characterize the effect of bleaching on the flavor of liquid and spray-dried Cheddar whey. Cheddar cheeses colored with water-soluble annatto were manufactured in duplicate. Four bleaching treatments (HP, 250 and 500 mg/kg and BPO, 10 and 20 mg/kg) were applied to liquid whey for 1.5 h at 60 degrees C followed by cooling to 5 degrees C. A control whey with no bleach was also evaluated. Flavor of the liquid wheys was evaluated by sensory and instrumental volatile analysis. One HP treatment and one BPO treatment were subsequently selected and incorporated into liquid whey along with an unbleached control that was processed into spray-dried WPC. These trials were conducted in triplicate. The WPC were evaluated by sensory and instrumental analyses as well as color and proximate analyses. The HP-bleached liquid whey and WPC contained higher concentrations of oxidation reaction products, including the compounds heptanal, hexanal, octanal, and nonanal, compared with unbleached or BPO-bleached liquid whey or WPC. The HP products were higher in overall oxidation products compared with BPO samples. The HP liquid whey and WPC were higher in fatty and cardboard flavors compared with the control or BPO samples. Hunter CIE Lab color values (L*, a*, b*) of WPC powders were distinct on all 3 color scale parameters, with HP-bleached WPC having the highest L* values. Hydrogen peroxide resulted in a whiter WPC and higher off-flavor intensities; however, there was no difference in norbixin recovery between HP and BPO. These results indicate that the bleaching of liquid whey may affect the flavor of WPC and that the type of bleaching agent used may affect WPC flavor.
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Radical cyclization of beta-alkoxyacrylates: synthesis of a C2-symmetric, L-shaped molecule with four fused tetrahydropyran rings. Chirality 2000; 12:360-1. [PMID: 10824152 DOI: 10.1002/(sici)1520-636x(2000)12:5/6<360::aid-chir10>3.0.co;2-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A C2-symmetric, L-shaped tetracycle with four fused tetrahydropyran rings was synthesized from (3R, 4R)-1, 6-dibenzoyloxy-hexane-3, 4-diol employing radical cyclization reactions of beta-alkoxyacrylates.
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