DHA Induces Cell Death through the Production of ROS and the Upregulation of CHOP in Fibroblast-like Synovial Cells from Human Rheumatoid Arthritis Patients.

Rheumatoid arthritis (RA) is an inflammatory disease marked by a massive proliferation of synovial cells in the joints. In this study, we investigated the pro-apoptotic effects of docosahexaenoic acid (DHA) in human fibroblast-like synovial cells from RA patients (RA-FLS). An in vitro study using MH7A cells showed that DHA treatment induced caspase-8-dependent apoptosis in a dose-dependent manner and reduced the TNF-α-mediated induction of MMP-9 and IL-1ß. DHA also induced the phosphorylation of eIF2α, the expression of the ER stress markers ATF4 and C/EBP homologous protein (CHOP), and death receptor 5 (DR5). The knockdown of CHOP or DR5 increased cell viability and reduced apoptosis in DHA-treated cells. Furthermore, the knockdown of CHOP reduced DHA-mediated DR5 expression, while the overexpression of CHOP increased DR5 expression. We also found that DHA treatment induced the accumulation of reactive oxygen species (ROS), and pretreatment with the anti-oxidant Tiron effectively abrogated not only the expression of CHOP and DR5, but also DHA-induced apoptosis. Under this condition, cell viability was increased, while PARP-1 cleavage and caspase-8 activation were reduced. All the findings were reproduced in human primary synovial cells obtained from RA patients. These results suggest that the DHA-mediated induction of ROS and CHOP induced apoptosis through the upregulation of DR5 in RA-FLSs, and that CHOP could be used as a therapy for RA.

PKR-Mediated Phosphorylation of eIF2a and CHK1 Is Associated with Doxorubicin-Mediated Apoptosis in HCC1143 Triple-Negative Breast Cancer Cells.

Triple-negative breast cancer is more aggressive than other types of breast cancer. Protein kinase R (PKR), which is activated by dsRNA, is known to play a role in doxorubicin-mediated apoptosis; however, its role in DNA damage-mediated apoptosis is not well understood. In this study, we investigated the roles of PKR and its downstream players in doxorubicin-treated HCC1143 triple-negative breast cancer cells. Doxorubicin treatment induces DNA damage and apoptosis. Interestingly, doxorubicin treatment induced the phosphorylation of eukaryotic initiation factor 2 alpha (eIF2α) via PKR, whereas the inhibition of PKR with inhibitor C16 reduced eIF2α phosphorylation. Under these conditions, doxorubicin-mediated DNA fragmentation, cell death, and poly(ADP ribose) polymerase and caspase 7 levels were recovered. In addition, phosphorylation of checkpoint kinase 1 (CHK1), which is known to be involved in doxorubicin-mediated DNA damage, was increased by doxorubicin treatment, but blocked by PKR inhibition. Protein translation was downregulated by doxorubicin treatment and upregulated by blocking PKR phosphorylation. These results suggest that PKR activation induces apoptosis by increasing the phosphorylation of eIF2α and CHK1 and decreasing the global protein translation in doxorubicin-treated HCC1143 triple-negative breast cancer cells.

Therapeutic Response Monitoring with 89Zr-DFO-Pertuzumab in HER2-Positive and Trastuzumab-Resistant Breast Cancer Models.

Immuno-positron emission tomography (PET) has great potential to evaluate the target expression level and therapeutic response for targeted cancer therapy. Immuno-PET imaging with pertuzumab, due to specific recognition in different binding sites of HER2, could be useful for the determination of the therapeutic efficacy of HER2-targeted therapy, trastuzumab, and heat shock protein 90 (HSP90) inhibitor, in HER2-expressing breast cancer. The aim of this study is to evaluate the feasibility of monitoring therapeutic response with 89Zr-DFO-pertuzumab for the treatment of HER2-targeted therapeutics, trastuzumab, or the HSP90 inhibitor 17-DMAG, in trastuzumab-resistant JIMT-1 breast cancer models. We prepared an immuno-PET imaging agent using desferoxamine (DFO)-pertuzumab labeled with 89Zr and performed the biodistribution and PET imaging in breast cancer xenograft models for monitoring therapeutic response to HER2-targeted therapy. 89Zr-DFO-pertuzumab was successfully prepared and showed specific binding to HER2 in vitro and clearly visualized HER2 expressing JIMT-1 tumors. 89Zr-DFO-pertuzumab had prominent tumor uptake in HER2 expressing JIMT-1 tumors. JIMT-1 tumors showed trastuzumab-resistant and HSP90 inhibitor sensitive characterization. In immuno-PET imaging, isotype antibody-treated JIMT-1 tumors had similar uptake in trastuzumab-treated JIMT-1 tumors, but 17-DMAG-treated JIMT-1 tumors showed greatly reduced uptake compared to vehicle-treated tumors. Additionally, HER2 downregulation evaluated by immuno-PET imaging was verified by western blot analysis and immunofluorescence staining which resulted in a significant reduction in the tumor's HER2 level in 17-DMAG-treated JIMT-1 tumors. 89Zr-DFO-pertuzumab immuno-PET may be clinically translated to select pertinent patients for HER2-targeted therapy and to monitor the therapeutic response in HER2-positive cancer patients under various HER2-targeted therapeutics treatments.

Preparation of Squalene Oil-Based Emulsion Adjuvants Employing a Self-Emulsifying Drug Delivery System and Assessment of Mycoplasma hyopneumoniae-Specific Antibody Titers in BALB/c Mice.

In this study, a self-emulsifying drug delivery system (SEDDS) was employed to prepare novel squalene oil-based emulsion adjuvants. Deionized water, 0.01% and 0.02% (w/v) carbomer solutions of C-971P NF and C-940 grades were used to prepare emulsions containing 3%, 5% and 10% of squalene oil. Altogether 15 candidate emulsions were prepared and used as adjuvants for the delivery of a combination vaccine containing a porcine circovirus type 2 (PCV2) antigen and inactivated Mycoplasma hyopneumoniae (J101 strain) antigen. Most of the emulsions showed droplet sizes in the submicron range and maintained zeta potential values between -40 mV to 0 mV for six months, indicating good physical stability as a vaccine adjuvant. Emulsion-based candidate adjuvants prepared with SEDDS technology stimulated IgG, IgG1 and IgG2a like a currently commercially available adjuvant, Montanide ISATM 201, and they were safe and their Mycoplasma hyopneumoniae-specific antibody titers were considered as comparable with that of Montanide ISATM 201.

Detection of 8-oxoguanine and apurinic/apyrimidinic sites using a fluorophore-labeled probe with cell-penetrating ability.

BACKGROUND: Reactive oxygen species (ROS) produce different lesions in DNA by ROS-induced DNA damage. Detection and quantification of 8-oxo-7,8-dihydroguanine (8-oxoG) within cells are important for study. Human ribosomal protein S3 (hRpS3) has a high binding affinity to 8-oxoG. In this study, we developed an imaging probe to detect 8-oxoG using a specific peptide from hRpS3. Transactivator (TAT) proteins are known to have cell-penetrating properties. Therefore, we developed a TAT-S3 probe by attaching a TAT peptide to our imaging probe. RESULTS: A DNA binding assay was conducted to confirm that our probe bound to 8-oxoG and apurinic/apyrimidinic (AP) sites. We confirmed that the TAT-S3 probe localized in the mitochondria, without permeabilization, and fluoresced in H2O2-treated HeLa cells and zebrafish embryos. Treatment with Mitoquinone (MitoQ), a mitochondria-targeted antioxidant, reduced TAT-S3 probe fluorescence. Additionally, treatment with O8, an inhibitor of OGG1, increased probe fluorescence. A competition assay was conducted with an aldehyde reaction probe (ARP) and methoxyamine (MX) to confirm binding of TAT-S3 to the AP sites. The TAT-S3 probe showed competitive binding to AP sites with ARP and MX. CONCLUSIONS: These results revealed that the TAT-S3 probe successfully detected the presence of 8-oxoG and AP sites in damaged cells. The TAT-S3 probe may have applications for the detection of diseases caused by reactive oxygen species.

Development of a Theranostic Convergence Bioradiopharmaceutical for Immuno-PET Based Radioimmunotherapy of L1CAM in Cholangiocarcinoma Model.

PURPOSE: Cholangiocarcinoma is a malignancy of bile duct with a poor prognosis. Conventional chemotherapy and radiotherapy are generally ineffective, and surgical resection is the only curative treatment for cholangiocarcinoma. L1-cell adhesion molecule (L1CAM) has been known as a novel prognostic marker and therapeutic target for cholangiocarcinoma. This study aimed to evaluate the feasibility of immuno-PET imaging-based radioimmunotherapy using radiolabeled anti-L1CAM antibody in cholangiocarcinoma xenograft model. EXPERIMENTAL DESIGN: We prepared a theranostic convergence bioradiopharmaceutical using chimeric anti-L1CAM antibody (cA10-A3) conjugated with 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) chelator and labeled with 64Cu or 177Lu and evaluated the immuno-PET or SPECT/CT imaging and biodistribution with 64Cu-/177Lu-cA10-A3 in various cholangiocarcinoma xenograft models. Therapeutic efficacy and response monitoring were performed by 177Lu-cA10-A3 and 18F-FDG-PET, respectively, and immunohistochemistry was done by TUNEL and Ki-67. RESULTS: Radiolabeled cA10-A3 antibodies specifically recognized L1CAM in vitro, clearly visualized cholangiocarcinoma tumors in immuno-PET and SPECT/CT imaging, and differentiated the L1CAM expression level in cholangiocarcinoma xenograft models. 177Lu-cA10-A3 (12.95 MBq/100 µg) showed statistically significant reduction in tumor volumes (P < 0.05) and decreased glucose metabolism (P < 0.01). IHC analysis revealed 177Lu-cA10-A3 treatment increased TUNEL-positive and decreased Ki-67-positive cells, compared with saline, cA10-A3, or 177Lu-isotype. CONCLUSIONS: Anti-L1CAM immuno-PET imaging using 64Cu-cA10-A3 could be translated into the clinic for characterizing the pharmacokinetics and selecting appropriate patients for radioimmunotherapy. Radioimmunotherapy using 177Lu-cA10-A3 may provide survival benefit in L1CAM-expressing cholangiocarcinoma tumor. Theranostic convergence bioradiopharmaceutical strategy would be applied as imaging biomarker-based personalized medicine in L1CAM-expressing patients with cholangiocarcinoma.

Classification, bacteriological findings, and analysis of sex hormone receptors and cytokine expression in mammary lesions of abattoir sows.

Mammary lesions in sows can prevent suckling piglets from consuming colostrum that provides fundamental nutrients and protective immunity. Although mammary gross lesions are frequently found in sows at farms or slaughterhouses, with the exception of mastitis, they have received little research attention. In this study, we investigated mammary lesions observed in South Korean sows between 2015 and 2016. Mammary tissue samples of 82 sows showing gross lesions during meat inspection were histologically classified and immunohistochemical analysis was conducted to assess the expression of estrogen receptor (ER)-α, ER-ß, and progesterone receptor (PR) for mammary hyperplastic lesions as well as that of cluster of differentiation (CD) 3, CD79a, interleukin (IL)-1α, IL-1ß, IL-6, and IL-8 for mastitis. Furthermore, 20 swab samples were cultured, and the isolated bacteria were identified using polymerase chain reactions for 16S ribosomal RNA genes. The lesions were classified as hyperplasia, mastitis, or hyperplasia with mastitis. Immunohistochemistry results revealed that there was neither expression of ER-α nor of ER-ß, but all examined hyperplastic samples expressed PR. In addition, there was a significant correlation between CD3 and IL-1ß expressions, as well as between IL-1ß and IL-6 expressions. Regarding the identity of the isolated bacteria, Pseudomonas spp. were most frequently detected. The results of this study have revealed the incidence and characteristics of porcine mammary lesions.

G-Protein-Coupled Receptor 120 Mediates DHA-Induced Apoptosis by Regulating IP3R, ROS and, ER Stress Levels in Cisplatin-Resistant Cancer Cells.

The omega-3 fatty acid docosahexaenoic acid (DHA) is known to induce apoptosis and cell cycle arrest via the induction of reactive oxygen species (ROS) production and endoplasmic reticulum (ER) stress in many types of cancers. However, the roles of DHA in drug-resistant cancer cells have not been elucidated. In this study, we investigated the effects of DHA in cisplatin-resistant gastric cancer SNU-601/cis2 cells. DHA was found to induce ROS-dependent apoptosis in these cells. The inositol 1,4,5-triphosphate receptor (IP3R) blocker 2-aminoethyl diphenylboninate (2-APB) reduced DHA-induced ROS production, consequently reducing apoptosis. We also found that G-protein-coupled receptor 120 (GPR120), a receptor of long-chain fatty acids, is expressed in SNU-601/cis2 cells, and the knockdown of GPR120 using specific shRNAs alleviated DHA-mediated ROS production and apoptosis. GPR120 knockdown reduced the expression of ER stress response genes, similar to the case for the pre-treatment of the cells with N-acetyl-L-cysteine (NAC), an ROS scavenger, or 2-APB. Indeed, the knockdown of C/EBP homologous protein (CHOP), a transcription factor that functions under ER stress conditions, markedly reduced DHA-mediated apoptosis, indicating that CHOP plays an essential role in the anti-cancer activity of DHA. These results suggest that GPR120 mediates DHA-induced apoptosis by regulating IP3R, ROS, and ER stress levels in cisplatin-resistant cancer cells, and that GPR120 is an effective chemotherapeutic target for cisplatin resistance.

Determination of Mycoplasma hyopneumoniae-Specific IgG, IgG1, and IgG2a Titers in BALB/c Mice Induced by Mineral Oil-Based Oil-in-Water Emulsion Adjuvants Prepared Using a Self-Emulsifying Drug Delivery System.

We prepared mineral oil-based emulsion adjuvants by employing simple self-emulsifying drug delivery system (SEDDS). Mineral oil emulsions (3%, 5%, and 7%) were prepared using deionized water and C-971P NF and C-940 grade carbomer solutions with concentrations 0.01% (w/v) and 0.02% (w/v). In total, 15 emulsions were prepared and mixed with a solution containing inactivated Mycoplasma hyopneumoniae (J101 strain) antigen and porcine circovirus type 2 antigen to prepare vaccines. Droplet sizes in the submicron range and zeta potential values between - 40 and 0 mV were maintained by most emulsion adjuvants for a period of 6 months. Emulsion adjuvants were regarded safe, and their M. hyopneumoniae-specific IgG, IgG1, and IgG2a titers were either better or comparable to those of aluminum gel.

PET Imaging Biomarkers of Anti-EGFR Immunotherapy in Esophageal Squamous Cell Carcinoma Models.

Epidermal growth factor receptor (EGFR) is overexpressed and considered as a proper molecular target for diagnosis and targeted therapy of esophageal squamous cell carcinoma (ESCC). This study evaluated the usefulness of PET imaging biomarkers with 64Cu-PCTA-cetuximab and 18F-FDG-PET for anti-EGFR immunotherapy in ESCC models. In vivo EGFR status and glucose metabolism by cetuximab treatment were evaluated using 64Cu-PCTA-cetuximab and 18F-FDG-PET, respectively. Therapeutic responses with imaging biomarkers were confirmed by western blot and immunohistochemistry. TE-4 and TE-8 tumors were clearly visualized by 64Cu-PCTA-cetuximab, and EGFR expression on TE-8 tumors showed 2.6-fold higher uptake than TE-4. Tumor volumes were markedly reduced by cetuximab in TE-8 tumor (92.5 ± 5.9%), but TE-4 tumors were refractory to cetuximab treatment. The SUVs in 64Cu-PCTA-cetuximab and 18F-FDG-PET images were statistically significantly reduced by cetuximab treatment in TE-8 but not in TE-4. 64Cu-PCTA-cetuximab and 18F-FDG-PET images were well correlated with EGFR and pAkt levels. 64Cu-PCTA-cetuximab immuno-PET had a potential for determining EGFR level and monitoring therapeutic response by anti-EGFR therapy. 18F-FDG-PET was also attractive for monitoring efficacy of anti-EGFR therapy. In conclusion, PET imaging biomarkers may be useful for selecting patients that express target molecules and for monitoring therapeutic efficacy of EGFR-targeted therapy in ESCC patients.

Apoptotic and Anti-Inflammatory Effects of Eupatorium japonicum Thunb. in Rheumatoid Arthritis Fibroblast-Like Synoviocytes.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by synovitis, hyperplasia, and the destruction of bone and cartilage. A variety of immunosuppressive biological agents have been developed because the pathogenesis of RA is related predominantly to the inflammatory response. However, rheumatoid arthritis fibroblast-like synovial cells (RAFLS), which are known to play an important role in RA progression, exhibit resistance to immunosuppressants through cancer-like properties. In this study, we identified a novel therapeutic compound for RA, which reduced inflammation and the abnormal proliferation of RAFLS in natural product library made from Korean native plants. Eupatorium japonicum Thunb. (EJT) extract, a component of the natural product library, most effectively reduced viability through the induction of ROS-mediated apoptosis in a dose-dependent manner. In addition, the increased ROS induced the expression of ATF4 and CHOP, key players in ER stress-mediated apoptosis. Interestingly, EJT extract treatment dose-dependently reduced the expression of IL-1ß and the transcription of MMP-9, which were induced by TNF-α treatment, through the inhibition of NF-κB and p38 activation. Collectively, we found that EJT extract exerted apoptotic effects through increases in ROS production and CHOP expression and exerted anti-inflammatory effects through the suppression of NF-κB activation, IL-1ß expression, and MMP-9 transcription.

Angelica gigas Nakai Has Synergetic Effects on Doxorubicin-Induced Apoptosis.

Natural products are valuable sources for drug discovery because they have a wide variety of useful chemical components and biological properties. A quick reevaluation of the potential therapeutic properties of established natural products was made possible by the recent development of the methodology and improvement in the accuracy of an automated high-throughput screening system. In this study, we screened natural product libraries to detect compounds with anticancer effects using HeLa cells. Of the 420 plant extracts screened, the extract of Angelica gigas Nakai (AGN) was the most effective in reducing cell viability of HeLa cells. Markers of apoptosis, such as exposure of phosphatidylserine and cleavage of caspase-7 and PARP, were increased by treatment with the AGN extract. Treatment of the AGN extract increased expression of PKR as well as ATF4 and CHOP, the unfolded protein response genes. In addition, cotreatment of doxorubicin and the AGN extract significantly increased doxorubicin-induced apoptosis in HeLa cells. Decursin and decursinol angelate, which were known to have anticancer effects, were the main components of the AGN extract. These results suggest that the extract of AGN containing, decursin and decursinol angelate, increases doxorubicin susceptibility.

CD204-Expressing Tumor-Associated Macrophages Are Associated With Malignant, High-Grade, and Hormone Receptor-Negative Canine Mammary Gland Tumors.

Tumor-associated macrophages (TAMs) are an important component of leukocyte infiltration in tumors. TAMs can be classified into M1 and M2 phenotypes. In the present study, the expression of CD204, an M2-polarized macrophage receptor, was investigated by immunohistochemistry in the area surrounding TAMs in 101 cases of canine mammary gland tumor (CMT). We examined the relationship between M2-polarized TAMs and malignancy, histological subtype, histological grade, molecular subtype, hormone receptor (HR) status, and clinical obesity indices. The mean number of CD204-positive macrophages was significantly higher in malignant CMTs than in benign CMTs ( P = .000). The number of CD204-positive macrophages differed significantly between histological grades ( P = .000) and were significantly higher in grade III than in grades I and II. Moreover, the mean number of CD204-positive macrophages was significantly higher in HR-negative malignant CMTs than in HR-positive malignant CMTs ( P = .035) and in malignant CMTs with lymphatic invasion compared to malignant CMTs without lymphatic invasion ( P = .000). These findings suggest that CD204-positive macrophages might affect the development and behavior of CMTs and highlight the potential of CD204 as a prognostic factor.

Differential and correlated expressions of p16/p21/p27/p38 in mammary gland tumors of aged dogs.

The inhibitory effect of neutering on mammary gland tumor development in dogs has been well described. However, we observed that the effect of neutering on tumor malignancy may be altered by aging. Therefore, we characterized mammary tumors in aged dogs by analyzing the expression of cellular senescence markers. Expressions of p16, p38, p21, and p27 antibodies, which are senescence-associated markers, were assessed in canine mammary tumors of aged dogs via immunohistochemical analysis. In addition, correlations between those expressions were analyzed. Expression of p16 was negatively associated with strong nuclear p27 expression. Expression of p38 was observed in most of the mammary tumors examined, and negative p38 expression was related to positive p21 expression. Moreover, p21 expression was associated with p27 expression; negative p21 expression was associated with negative p27 expression, while positive p21 expression was associated with positive p27 expression. The results confirm that the p21- and p27-encoding genes have similar expression patterns in the mammary tumors of aged dogs. In the present study, we characterized the expression of cellular senescence markers in these tumors and elucidated the relationships among their expression patterns.

Efficacy of clade 2.3.2 H5 commercial vaccines in protecting chickens from clade 2.3.4.4 H5N8 highly pathogenic avian influenza infection.

Emerging clade 2.3.4.4 of the highly pathogenic avian influenza (HPAI) virus strain H5N8, which had been detected sporadically in domestic poultry in China, started to affect wild birds and poultry in South Korea in 2014. The virus was spread to Germany, Italy, the Netherlands, United Kingdom, and even United States by migratory birds. Here, we tested currently used commercial clade 2.3.2 H5 vaccines to evaluate mortality, clinical signs, virus shedding, and histological damage after experimental infection of chickens with the clade 2.3.4.4 HPAI H5N8 virus. Although the vaccination protected chickens from death, it failed to prevent chickens from shedding the virus and from tissue damage according to histological examination. These results suggest that the use of appropriate vaccines that match the currently epidemic HPAI virus is recommended, and continuous HPAI surveillance and testing of currently used commercial vaccines should be performed.

Breed- and age-related differences in canine mammary tumors.

Triple-negative breast cancer is a type of breast cancer that does not express the genes for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2). It is an important and clinically relevant condition as it has a poor prognosis and is difficult to treat. Basal-like triple-negative cancer is highly prevalent in both African-Americans and adolescents. We therefore examined whether such a cancer likewise occurs in specific breeds and age groups in dogs, focusing on basal-like triple-negative cancer in particular. In this study, 181 samples from dogs with malignant mammary carcinoma from the 5 most common breeds and 2 age groups in Korea were analyzed. Histological classification and molecular subtyping, including assessment of immunohistochemical findings, were carried out. Twenty-five of 28 (89.3%) triple-negative carcinomas were identified as basal-like triple-negative carcinomas. Analysis of associations of classified factors revealed that the shih tzu breed (9/25, 36.0%) and advanced-age (19/25, 76.0%) groups were characterized by higher prevalence of basal-like triple-negative tumors with diverse histological types and of a higher grade. These results suggest that breed- and age-related differences can be identified in canine mammary carcinoma and, notably, in the shih tzu breed and at older ages. Further investigation of these distinguishing characteristics of the shih tzu breed is warranted.

Le cancer mammaire triple-négatif est un type de cancer mammaire qui n'exprime pas les gènes pour les récepteurs de l'oestrogène (RO), les récepteurs de la progestérone (RP), et les récepteurs pour le facteur de croissance épidermique humain-2 (REH-2). Il s'agit d'une condition importante et cliniquement significative étant donné son mauvais pronostic et la difficulté à le traiter. Le cancer triple-négatif de type basal est très prévalent chez les afro-américains et les adolescents. Nous avons donc voulu savoir si chez les chiens ce type de cancer est rencontré également dans des races spécifiques et dans des groupes d'âge précis, en se concentrant sur des cancers triple-négatifs de type basal en particulier. Dans la présente étude réalisée en Corée, 181 échantillons provenant de chiens avec des carcinomes mammaires malins des cinq races les plus communes et de deux groupes d'âge ont été analysés. Une classification histologique et un sous-typage moléculaire, incluant une évaluation des trouvailles immunohistochimiques, ont été réalisés. Vingt-cinq des 28 (89,3 %) des carcinomes triple-négatifs ont été identifiés comme étant des carcinomes triple-négatifs de type basal. Une analyse des associations des facteurs classés a révélé que les groupes de chiens de la race Shih tsu (9/25, 36,0 %) et d'un âge avancé (19/25, 76,0 %) étaient caractérisés par une prévalence plus élevée de tumeurs triple-négatives de type basal avec des types histologiques variés et de grade plus élevé. Ces résultats suggèrent que des différences reliées à la race et à l'âge peuvent être identifiés dans les carcinomes mammaires canins et, notamment, chez la race Shih tsu et à un âge plus avancé. Des études supplémentaires de ces caractéristiques distinctives de la race Shih tsu sont justifiées.(Traduit par Docteur Serge Messier).

Salubrinal-Mediated Upregulation of eIF2α Phosphorylation Increases Doxorubicin Sensitivity in MCF-7/ADR Cells.

Eukaryotic translation initiation factor 2 alpha (eIF2α), which is a component of the eukaryotic translation initiation complex, functions in cell death and survival under various stress conditions. In this study, we investigated the roles of eIF2α phosphorylation in cell death using the breast cancer cell lines MCF-7 and MCF-7/ADR. MCF-7/ADR cells are MCF-7-driven cells that have acquired resistance to doxorubicin (ADR). Treatment of doxorubicin reduced the viability and induced apoptosis in both cell lines, although susceptibility to the drug was very different. Treatment with doxorubicin induced phosphorylation of eIF2α in MCF-7 cells but not in MCF-7/ADR cells. Basal expression levels of Growth Arrest and DNA Damage 34 (GADD34), a regulator of eIF2α, were higher in MCF-7/ADR cells compared to MCF-7 cells. Indeed, treatment with salubrinal, an inhibitor of GADD34, resulted in the upregulation of eIF2α phosphorylation and enhanced doxorubicin-mediated apoptosis in MCF-7/ADR cells. However, MCF-7 cells did not show such synergic effects. These results suggest that dephosphorylation of eIF2α by GADD34 plays an important role in doxorubicin resistance in MCF-7/ADR cells.

Temporal Evolution of MRI Characteristics in Dogs with Collagenase-Induced Intracerebral Hemorrhage.

Intracerebral hemorrhage (ICH) is one of the most lethal types of stroke. Neuroimaging techniques, particularly MRI, have improved the diagnostic accuracy of ICH. The MRI characteristics of the evolving stages of ICH in humans-but not those in dogs-have been described. In this study, we document the temporal MRI characteristics in a canine model of collagenase-induced ICH. Specifically, ICH was induced in 5 healthy beagles by injecting 500 U of bacterial collagenase from Clostridium histolyticum, which was delivered into the parietal lobe over 5 min by using a microinfusion pump. T1- and T2-weighted, fluid-attenuated inversion recovery, gradient-echo (GRE), and diffusion-weighted (DWI) imaging and measurement of the apparent diffusion coefficient (ADC) were performed serially at 6 different time points (before and 12 h, 3 d, 5 d, 10 d and 24 d after hemorrhage) by using a 3-T MR system. The temporal changes of T1 signal intensity (SI) corresponded well with the reported human data. The temporal changes of T2 and GRE sequences, with the exception of T2 and GRE hyperintensities at the early subacute stage, also matched. ADC measurements were high at the early subacute stage, and DWI-SI positively correlated with T2- and GRE-SI from the early subacute stage onward. In conclusion, MRI is an ideal method for characterizing the temporal evolution of parenchymal alterations after ICH in dogs. These data might be useful for differentiating clinical stages of ICH in dogs.

Hempseed oil induces reactive oxygen species- and C/EBP homologous protein-mediated apoptosis in MH7A human rheumatoid arthritis fibroblast-like synovial cells.

ETHNOPHARMACOLOGICAL RELEVANCE: The medicinal efficacy of hempseed (Cannabis sativa L.), which is rich in polyunsaturated fatty acids, in atopic dermatitis, inflammation, and rheumatoid arthritis (RA) has been suggested for centuries. Hempseed has been used as a treatment for these diseases in Korean and Chinese folk medicine. The aim of the study is to investigate the effects of hempseed oil (HO) on MH7A human RA fibroblast-like synovial cells. MATERIALS AND METHODS: MH7A cells were used to study the anti-rheumatoid effects of hempseed (Cannabis sativa L., cv. Cheungsam/Cannabaceae) oil by investigating cell viability, apoptosis, lipid accumulation, oxidative stress, and endoplasmic reticulum (ER) stress-induced apoptosis. RESULTS: HO treatment reduced the survival rate of MH7A cells and promoted apoptotic cell death in a time- and dose-dependent manner. Both lipid accumulation and the level of intracellular reactive oxygen species (ROS) increased in HO-treated MH7A cells. Co-treatment with the antioxidant Tiron effectively abrogated the cytotoxic effects of HO; the ROS level was reduced, cell viability was recovered, and apoptotic cell death was significantly diminished. Moreover, HO-treated cells exhibited increased expression of the major ER stress markers, glucose-regulated protein 78 and C/EBP homologous protein (CHOP). The siRNA-mediated knockdown of CHOP prevented HO-induced apoptosis. CONCLUSIONS: Our results suggest that HO treatment induced lipid accumulation, ROS production, CHOP expression, and apoptosis in MH7A cells, and that CHOP functions as an anti-rheumatoid factor downstream of HO in MH7A cells.

Solvent dependent triphenylamine based D-(pi-A)n type dye molecules and optical properties.

D-(pi-A)n type dyes of triphenylamine derivatives were synthesized and their absorption and luminescence in different solvents were examined to investigate solvent dependent properties observed for their emissions in solvents with different dielectric constants. The emission wavelengths showed a dramatic blue shift with increasing solvent polarity. The results of molecular orbital calculations by computer simulation, based on Material Studio suite of programs, were found to reasonably account for the spectral properties. Relative levels of HOMO and LUMO were measured and calculated and all derivatives exhibited strong solid fluorescence with distinctively different FWHMs.