Dietary exposure experiments on the migration of chemical pollutants from microplastics to bivalves.

Plastics can contain two types of organic contaminants; absorbed from ambient water, and already contained as additives. To investigate the bioaccumulation of these substances, we conducted two types of exposure experiments using mussels and polyethylene microplastics with absorbed PCBs and containing four types of additives (BDE209, DBDPE, UV327 and UV234). After dietary exposure for 15 days, significantly higher concentrations of total PCBs, UV327 and UV234 were detected in the gonad of exposed groups than in the control groups, respectively. However, no significant differences in BDE209 or DBDPE levels were observed between the control and exposure groups. Although a higher transfer ratio was shown for PCB congeners with octanol-water partition coefficients (logKow) below 7, the ratio was lower for higher-hydrophobic PCBs with logKow above 7. This suggests that higher hydrophobic compounds (not only highly chlorinated PCBs, but also BDE209 and DBDPE) tend not to desorb or leach from plastics.

Association between the controlling nutritional status score and outcomes in ischemic stroke patients with active cancer.

BACKGROUND: The effect of nutritional status on survival in ischemic stroke patients with active cancer remains unclear. METHODS: This study retrospectively evaluated ischemic stroke patients with active cancer admitted to a university hospital in Japan between 2006 and 2016. Patients were followed for 2 years after stroke. The controlling nutritional status (CONUT) score was used to classify undernutrition degree into 4 groups: normal, light, moderate, and severe. Survival rates were compared using the Kaplan-Meier method. Hazard ratio (HR) and 95 % confidence intervals (CIs) for mortality were calculated using Cox regression models. RESULTS: A total of 158 patients (31 % women; median age: 71 years) were analyzed. Of these, 47 % had distant metastasis. The median (interquartile range) National Institute of Health Stroke Scale and CONUT scores were 4 (1-10) and 5 (3-7), respectively. Kaplan-Meier curve indicated that patients with poorer nutritional status had worse outcomes (overall log-rank test, p < 0.001). The univariable Cox regression analysis showed that the HR (95 % CI) for the light, moderate, and severe groups were 1.14 (0.45-2.86), 3.01 (1.27-7.12), and 2.94 (1.10-7.84), respectively. This statistical significance did not persist after adjustment for potential confounders (HR [95 % CI] for the light, moderate, and severe groups were 0.95 [0.36-2.49], 1.56 [0.57-4.28], and 1.34 [0.37-4.92], respectively). Past stroke, distant metastasis, and plasma D-dimer levels on admission were independent predictors of prognosis. CONCLUSIONS: This single-center, retrospective study suggests that nutritional status serves as a prognostic indicator for ischemic stroke patients with active cancer. However, the effect is not statistically independent.

Ischemic Stroke Due to Heparin-induced Thrombocytopenia during Severe COVID-19 Infection.

A 53-year-old woman with severe coronavirus disease 2019 (COVID-19) pneumonia was admitted and treated with intravenous unfractionated heparin for thromboprophylaxis under general anesthesia with mechanical ventilation. She developed right hemiparesis after hospitalization due to a large hemorrhagic infarction. Her platelet count decreased from 243,000/µL at administration to 121,000/µL. Anti-platelet factor 4-heparin antibody testing was positive according to a latex immunoturbidimetric assay. She was therefore diagnosed with heparin-induced thrombocytopenia. We immediately stopped the heparin and started argatroban; the platelet count recovered, and thrombosis did not relapse. Physicians should consider heparin-induced thrombocytopenia as a cause of ischemic stroke in patients with COVID-19 infection.

Pyrazolo pyrimidine-type inhibitors of SRC family tyrosine kinases promote ovarian steroid-induced differentiation of human endometrial stromal cells in vitro.

Reversible protein tyrosine phosphorylation, coordinately controlled by protein tyrosine kinases and phosphatases, is a critical element in signal transduction pathways regulating a wide variety of biological processes, including cell growth, differentiation, and tumorigenesis. We have previously reported that c-Src belonging to the Src family tyrosine kinase (SFK) becomes dephosphorylated at tyrosine 530 (Y530) and thereby activated during progestin-induced differentiation of human endometrial stromal cells (i.e., decidualization). In this study, to elucidate the role of decidual c-Src activation, we examined whether 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP1) and 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2), both potent and selective SFK inhibitors, affected the ovarian steroid-induced decidualization in vitro. Unexpectedly, PP1 paradoxically increased the kinase activity of decidual c-Src together with dephosphorylation of Y530 in the presence of ovarian steroids. Concomitantly, PP1 enhanced morphological and functional decidualization, as determined by induction of decidualization markers, such as insulin-like growth factor binding protein-1 and prolactin. PP2 also advanced decidualization along with up-regulation of the active form of c-Src whose Y-530 was dephosphorylated. In contrast to PP1 and PP2, herbimycin A, a tyrosine kinase inhibitor with less specificity for SFKs, showed little enhancing effect on the expression of both IGFBP-1 and active c-Src. These results suggest that SFKs, including c-Src, may play a significant role in stromal cell differentiation, providing a clue for a possible therapeutic strategy to modulate endometrial function by targeting signaling pathway(s) involving SFKs.

Involvement of histone acetylation in ovarian steroid-induced decidualization of human endometrial stromal cells.

Histone acetyltransferases and histone deacetylases (HDACs) determine the acetylation status of histones, regulating gene transcription. Decidualization is the progestin-induced differentiation of estrogen-primed endometrial stromal cells (ESCs), which is crucial for implantation and maintenance of pregnancy. We here show that trichostatin A (TSA), a specific HDAC inhibitor, enhances the up-regulation of decidualization markers such as insulin-like growth factor binding protein-1 (IGFBP-1) and prolactin in a dose-dependent manner that is directed by 17beta-estradiol (E(2)) plus progesterone (P(4)) in cultured ESCs, but not glandular cells, both isolated from human endometrium. Morphological changes resembling decidual transformation were also augmented by co-addition of TSA. Acid urea triton gel analysis and immunoblot using acetylated histone type-specific antibodies demonstrated that treatment with E(2) plus P(4) significantly increased the levels of acetylated H3 and H4 whose increment was augmented by co-treatment with TSA. Chromatin immunoprecipitation assay revealed that treatment with E(2) plus P(4) increased the amount of proximal progesterone-responsive region of IGFBP-1 promoter associated with acetylated H4, which was dramatically enhanced by co-addition of TSA. Taken together, our results suggest that histone acetylation is deeply involved in differentiation of human ESCs and that TSA has a potential as an enhancer of decidualization through promotion of progesterone action.

Expression and subcellular distribution of the active form of c-Src tyrosine kinase in differentiating human endometrial stromal cells.

Decidual growth factors and locally produced cytokines are thought to activate specific phosphorylation signalling pathway(s), thereby eliciting a variety of decidual functions. We have previously reported the activation of c-Src tyrosine kinase during ovarian steroid-induced decidualization of cultured human endometrial stromal cells. As chicken c-Src is known to be activated upon dephosphorylation of tyrosine 527 (Y527, corresponding to Y530 in human), we here employed a monoclonal antibody, clone 28, directed against the active form of human c-Src whose Y530 is dephosphorylated, and investigated whether c-Src became dephosphorylated at Y530 and thereby activated during decidualization. We found that the active form of c-Src was up-regulated and demonstrated increased kinase activity during in-vitro decidualization. Immunohistochemistry revealed that decidual cells in early pregnancy decidua were intensely stained with clone 28 when compared with the stromal cells in the non-pregnant endometrium. Moreover, the active form of c-Src translocated from a perinuclear region to the cytoplasm upon decidualization. Thus, the Y530 dephosphorylation, kinase activation, and subcellular translocation of c-Src may be intracellular signalling events associated with decidualization in vivo as well as in vitro.