Expression level of enzymes related to in situ estrogen synthesis and clinicopathological parameters in breast cancer patients

In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues.     

Concurrent Bursty Behavior of Social Sensors in Sporting Events

The advent of social media expands our ability to transmit information and connect with others instantly, which enables us to behave as “social sensors.” Here, we studied concurrent bursty behavior of Twitter users during major sporting events to determine their function as social sensors. We show that the degree of concurrent bursts in tweets (posts) and retweets (re-posts) works as a strong indicator of winning or losing a game. More specifically, our simple tweet analysis of Japanese professional baseball games in 2013 revealed that social sensors can immediately react to positive and negative events through bursts of tweets, but that positive events are more likely to induce a subsequent burst of retweets. We confirm that these findings also hold true for tweets related to Major League Baseball games in 2015. Furthermore, we demonstrate active interactions among social sensors by constructing retweet networks during a baseball game. The resulting networks commonly exhibited user clusters depending on the baseball team, with a scale-free connectedness that is indicative of a substantial difference in user popularity as an information source. While previous studies have mainly focused on bursts of tweets as a simple indicator of a real-world event, the temporal correlation between tweets and retweets implies unique aspects of social sensors, offering new insights into human behavior in a highly connected world.     

Specific interaction of arabinose residue in ginsenoside with egg phosphatidylcholine vesicles

The interaction of the specific sugar residue in ginsenosides with egg phosphatidylcholine vesicles was investigated by ESR spectrometry using phosphatidic acid spin-labeled at the polar head groups. Ginsenoside-Rc, which has an alpha-L-arabinofuranose residue and agglutinability toward egg yolk phosphatidylcholine vesicles (Fukuda, K. et al. (1985) Biochim. Biophys. Acta 820, 199-206), caused the restriction of the segmental motion of spin-labeled phosphatidic acid in egg phosphatidylcholine vesicles, indicating that the saponin interacted with the polar head groups of vesicles. Other ginsenosides-Rb2, Rb1, Rd and p-nitrophenyl glycoside derivatives which have less or no agglutinability were also investigated in the same manner. Only ginsenoside-Rb2 and p-nitrophenyl alpha-L-arabinofuranoside which have the specific sugar residue (arabinose) showed a strong interaction with the polar head groups of vesicles. To gain an insight into the mechanism of agglutination by ginsenoside-Rc, the interaction with the fatty acyl groups was also studied by using phosphatidylcholine spin-labeled at the fatty acyl groups. Ginsenoside-Rc increased the order parameter of the spin-labeled phosphatidylcholine, indicating that the saponin was inserted into lipid bilayers. In other saponins investigated, only ginsenoside-Rb2 interacted with the fatty acyl part of vesicles. The process of expression of agglutination by ginsenoside-Rc was discussed on the basis of the ESR studies.     

ESR study on synthetic glyceroglycolipid liposomal membranes

We previously reported that glyceroglycolipid liposomes without cholesterol activated mouse peritoneal macrophages in vivo and in vitro, whereas glyceroglycolipid liposomes containing equimolar cholesterol did not. In order to characterize the properties of the glyceroglycolipid membranes, ESR spectroscopic studies were carried out with an acyl spin-labeled galactosyl ceramide (SL-GC) or a headgroup spin-labeled phospholipid (SL-6-DPPA) in 1,2-dipalmitoyl[beta-cellobiosyl-(1'---3)]glycerol (Cel-DAG) liposomal membranes. The ESR spectrum of the SL-GC in the Cel-DAG liposomes at 37 degrees C was a single broad line, indicating that the SL-GC molecules were excluded almost completely from Cel-DAG domains and formed clusters in the membranes. The spectrum of SL-6-DPPA in the Cel-DAG liposomes at 37 degrees C showed broad resonance lines with the central peak being the highest, while that at 60 degrees gave narrow lines with the low-field peak being the highest. This observation and rotational correlation time analysis showed that the molecular motions of spin-label moiety of the SL-6-DPPA were extremely restricted at 37 degrees C but not above Tc. These results suggest that below Tc the Cel-DAG molecules are packed tightly and restricted in motion in the membrane. Incorporation of cholesterol into the Cel-DAG liposomal membranes gave (1) the spectra of the SL-GC triplet, and (2) the spectra of the SL-6-DPPA narrow resonance with the low-field peak being the highest. These results suggest that cholesterol disturbs the rigid-packed structure of the Cel-DAG membrane and increases the molecular motions of the Cel-DAG. The DSC analysis of Cel-DAG with and without cholesterol agreed well to the results of the ESR technique. Thus we assume that peritoneal macrophages recognize the rigid-packed carbohydrate residues which are restricted in motion on the Cel-DAG membranes.     

Lidocaine inhibits stimulation-coupled responses of neutrophils and protein kinase C activity

The effects of lidocaine, a local anesthetic, on various stimulation-coupled responses of neutrophils were studied. Superoxide generation, generation of chemiluminescence, depolarization of membrane potential and transitional increase in intracellular Ca2+ were inhibited by lidocaine in a concentration dependent manner. Lidocaine also inhibited Ca(2+)-activated phospholipid-dependent protein kinase (PKC) in the presence of various concentrations of Ca2+, phosphatidylserine and dioleoylglycerol. For the inhibition of all these stimulation-coupled responses, a similar order of the lidocaine concentration was needed. As in the case of dibucaine (Mori, T., Takai, Y., Minakuchi, R., Yu, B. and Nishizuka, Y., J. Biol. Chem. 255:8378-8380, 1980), lidocaine inhibited PKC activity in a manner competitive with phosphatidylserine. Lidocaine also inhibited the phosphorylation of 47 kDa neutrophil cytosplasmic protein, a phosphorylated protein required for NADPH oxidase activation. Thus, the cellular membrane phospholipid may be one of the target sites of lidocaine for the inhibitory action on the various stimulation-coupled responses of neutrophils, and these effects of lidocaine may correlate with its inhibitory action on PKC activity.     

Isolation of a cAMP-requiring mutant in Escherichia coli K-12: evidence of growth regulation via N-acetylglucosamine metabolism controlled by cAMP

Abstract An adenylate cyclase gene ( cya ) mutant was mutagenized and an adenosine 3,5-cyclic monophosphate (cAMP)-requiring mutant (KM8161) was obtained on Davis minimal medium containing glucose in the presence or absence of cAMP. KM8161 also required N -acetylglucosamine for its growth instead of cAMP. Furthermore, the mutant could use neither glucosamine nor N -acetylglucosamine as the carbon source. These results indicate that the cAMP-requiring property is due to multiple mutations of a few genes involved in amino sugar metabolism in addition to cya . By genetic analysis of KM8161, one gene, which was tentatively termed cidA and located near 2 min on the chromosomal map, proved to be defective. Reversion of cidA mutation in KM8161 resulted in recovery of not only the cAMP-requiring phenotype but also non-utilization of amino sugars. When both cAMP and N -acetylglucosamine or glucosamine were added to the culture medium for KM8161, only N -acetylglucosamine could be utilized as the carbon source. These studies s strongly suggest that the cidA or cya mutation in KM8161 causes deficiency in different stages of amino sugar metabolism and the regulatory circuit of growth by cAMP is mediated via control of N -acetylglucosamine metabolism.     

Intranuclear microinjection for transformation of tomato callus cells

An efficient method, called the culture plate method, was devised for microinjection of foreign materials into nuclei of tomato callus cells. The culture plate method, used in this study, is advantageous because cells suitable for microinjection can be selected microscopically and the injected cells subsequently cultured in the same plate. With this microinjection system, some foreign materials were injected into nuclei of callus cells without causing detrimental effects. Kanamycin-resistant callus clones were obtained 1 month after injection from single cells whose nuclei were microinjected with a NPT II DNA fragment of the pE2KX plasmid.     

Inhibition of neutrophil priming and tyrosyl phosphorylation by cepharanthine, a nonsteroidal antiinflammatory drug.

Receptor-mediated superoxide (O2.-)-generation and tyrosyl phosphorylation of neutrophil proteins, such as 58, 65, 84, 108 and 115 kDa, were enhanced by priming cells with granulocyte colony stimulating factor (G-CSF) [Akimura, K. et al. Arch. Biochem. Biophys. 298: 703-709, 1992]. To elucidate the possible involvement of tyrosyl phosphorylation of neutrophil proteins in the enhancing mechanism of O2.- generation, the effect of cepharanthine, a biscoclaurine alkaloid that inhibits phorbol 12-myristate 13-acetate (PMA)- and receptor-mediated O2.- generation, on the priming of human peripheral neutrophils (HPPMN) was studied. Both enhancement of formyl-methionyl-leucyl- phenylalanine (FMLP)-mediated O2.- generation and tyrosyl phosphorylation of some neutrophil proteins, i.e., 115, 108 and 84 kDa proteins, by HHPMN after treatment with G-CSF were strongly inhibited by cepharanthine in a concentration- and treatment-time-dependent manner. In contrast, inhibition of PMA-mediated O2.- generation by cepharanthine was weak and independent of treatment time. These results suggest that cepharanthine might inhibit the priming step of neutrophil activation concomitantly with its inhibition of the tyrosyl phosphorylation of some neutrophil proteins that might underlie the mechanism for priming of neutrophils with G-CSF.