Permeation of Zidovudine and Probenecid from Oily Bases Containing Alcohols Through Rat Skin

Permeation of zidovudine (3'-azido-3'-deoxythymidine, AZT) and probenecid from oily bases containing an alcohol through rat skin was examined. Isopropyl myristate (IPM), as an oily vehicle, showed a penetration enhancing effect for AZT and probenecid. Ethanol, n-propanol, and n-butanol were used as additives in IPM and were examined for their own permeation and the enhancing effect on the permeation of AZT and probenecid. The skin permeation of AZT and probenecid from IPM was enhanced by addition of the alcohol in IPM. The degree of the enhancement was decreased with increasing lipophilicity of the alcohol used. me permeation rate of the drug from those systems was shown to be governed by penetration-enhancing effects of the oily base and alcohol, and the penetration of the alcohol itself through the skin.     

Allelopathic Effects of Volatile Monoterpenoids Produced by <Emphasis Type="Italic">Salvia leucophylla</Emphasis>: Inhibition of Cell Proliferation and DNA Synthesis in the Root Apical Meristem of <Emphasis Type="Italic">Brassica campestris</Emphasis> Seedlings

Salvia leucophylla, a shrub observed in coastal south California, produces several volatile monoterpenoids (camphor, 1,8-cineole, -pinene, -pinene, and camphene) that potentially act as allelochemicals. The effects of these were examined using Brassica campestris as the test plant. Camphor, 1,8-cineole, and -pinene inhibited germination of B. campestris seeds at high concentrations, whereas -pinene and camphene did not. Root growth was inhibited by all five monoterpenoids in a dose-dependent manner, but hypocotyl growth was largely unaffected. The monoterpenoids did not alter the sizes of matured cells in either hypocotyls or roots, indicating that cell expansion is relatively insensitive to these compounds. They did not decrease the mitotic index in the shoot apical region, but specifically lowered mitotic index in the root apical meristem. Moreover, morphological and biochemical analyses on the incorporation of 5-bromo-2-deoxyuridine into DNA demonstrated that the monoterpenoids inhibit both cell-nuclear and organelle DNA synthesis in the root apical meristem. These results suggest that the monoterpenoids produced by S. leucophylla could interfere with the growth of other plants in its vicinity through inhibition of cell proliferation in the root apical meristem.     

Simulation of chain length recognition observed in formation of inclusion complex

We carried out Brownian dynamics simulations to investigate the mechanism of chain length recognition observed in the formation of inclusion complexes (ICs) between cyclodextrins (CDs) and polymer chains. In our simulations, we used rings and chains as models to represent CDs and polymer chains, respectively. We used two types of chains with different lengths to determine which chain was preferred by the rings to form ICs. At low concentration of rings, we observed that almost all the rings formed ICs with the long chains. Chain length recognition could be reproduced in our simulation, and it occurred because of the difference in the inclusion time between the long chains and the short chains in the ICs. On the other hand, at high concentration of rings, the number of rings forming ICs with the long chains increased, and pseudo-polyrotaxanes (PPRXs) were formed. ICs were also formed with the short chains, because the inclusion time for each ring contained in the PPRXs reduced with an increase in the number of rings therein, and then, the dissociated rings formed ICs with the short chains. As a result, chain length recognition was not observed. From these results, we conclude that the difference in the inclusion time between the rings and the chains controls chain length recognition.     

Modification of physicochemical properties of actin filaments suppresses cell fragmentation in the execution phase of staurosporine-induced apoptotic processes

Effects of jasplakinolide (JSP), a stabilizer of F-actin, and latrunculin A (LTA), a destabilizer of F-actin, on a series of events occurring in the execution phase of staurosporine (STS)-induced apoptotic processes were studied using human osteosarcoma 143B cells. Time-dependent apparent increases of the population of cells with collapsed membrane potential of mitochondria (Delta Psi(m)) caused by STS treatment were not due to actual decreases in the Delta Psi(m) per cell, but due to the fragmentation of cells resulting in decreases in the number of active mitochondria per cell. Decreases in the Delta Psi(m) in fragmented cells occurred late in the execution phase. Both JSP and LAT failed to prevent STS-induced release of cytochrome c from mitochondria followed by the activation of caspases 3 and 9, the cleavage of poly (ADP-ribose) polymerase (PARP) and apoptotic nuclear fragmentation. However, both drugs prevented STS-induced apoptotic cell fragmentation and decreases in the Delta Psi(m). These results indicate that physicochemical states of actin filaments play a certain role in the execution phase of STS-induced apoptotic processes.     

Attenuation of ischemic liver injury by prostaglandin E1 analogue, misoprostol, and prostaglandin I2 analogue, OP-41483

Workplace AIDS training is a recent addition to many corporations' occupational health agenda. However, little is known about the objectives, content, and practices of AIDS training programs. A survey of 126 workplace AIDS trainers was conducted to determine the impact of the trainer's organizational affiliation (in-house, consultant, union, etc.) and personal motives on training program objectives, content, and practices. Results indicate that the organizational affiliation of trainers is significantly related to training objectives, topics, and practices, whereas strong personal motives for becoming an AIDS trainer is significantly associated with an emphasis on more controversial content areas and training practices. Findings are discussed in terms of applicability to other values-oriented training topics, applications to practice, and future research needs.     

Cloning and some properties of Japanese pear (Pyrus pyrifolia) polyphenol oxidase,and changes in browning potential during fruit maturation

A PCR‐amplified genomic DNA fragment encoding Japanese pear (Pyrus pyrifolia) polyphenol oxidase (PPO) was cloned and sequenced. The DNA appears to encode a 66 kDa precursor protein consisting of a 56 kDa mature protein and a 9.5 kDa N‐terminal transit peptide. The amino acid sequence showed high homology with apple PPO. The PPO mainly existed as a soluble fraction in cells and was limitedly proteolysed, while the mature form (56 kDa) was detected in plastids. Immature fruits showing high browning potential had high PPO activity and a high level of phenolics, while mature fruits showing little browning had high PPO activity but a low level of phenolics. Copyright © 2003 Society of Chemical Industry     

Intragenic Tsc2 somatic mutations as Knudson''s second hit in spontaneous and chemically induced renal carcinomas in the Eker rat model

Membrane conductances during hypoosmotic swelling were characterized in rat astrocytes in primary tissue culture. Using whole cell patch clamp techniques, mean +/- SEM cell conductance in isoosmotic phosphate-buffered saline (PBS) was 55.6 +/- 5.8 pS/pF. Cell conductance (mean +/- SEM) increased from this initial value to 187 +/- 46%, 561 +/- 188%, and 1216 +/- 376% within 9 min of exposure to 220 mOsm, 190 mOsm, and 145 mOsm PBS, respectively. With each of these hypoosmotic exposures, no change occurred in membrane capacitance. When CsCl replaced KCl in the microelectrode solution, a similar conductance increase was obtained at each osmolality. However, when gluconate salts were used in place of chloride salts in the electrode solution, no significant conductance increase was observed with 190 mOsm PBS. With a KCl microelectrode solution, all conductance increase which occurred in 190 mOsm PBS was inhibited by 200 microM niflumic acid, but not by 5 mM BaCl(2). Both niflumic acid and BaCl(2) inhibited 60-80% of the conductance increase of cells in 145 mOsm PBS. Using a microelectrode solution containing taurine as the major anion, membrane conductance increased 5-fold when cells were placed in 250 mOsm medium. This conductance increase was completely inhibited by 200 microM niflumic acid. Thus, independent chloride and potassium conductances are activated by hypoosmotic swelling of cultured astrocytes while plasma membrane area is unaltered. The chloride conductance pathway is activated at a significantly lower degree of hypoosmotic exposure than that which activates the potassium pathway and may be permeable to anionic taurine. These conductance pathways may mediate diffusive loss of potassium, chloride, and taurine from these cells during volume regulation following hypoosmotic swelling.     

Role of mitochondria in the switch mechanism of the cell death mode from apoptosis to necrosis--studies on rho0 cells

Detailed mechanisms of the switch of the cell death mode from apoptosis to necrosis remain to be solved, although the intracellular level of ATP and that of free radicals have been postulated to be the major factors involved in the mechanisms. In the present study menadione (MEN)-induced cell injury processes were studied using rho0 cells derived from human osteosarcoma 143B cells and parental rho+ cells co-treated with inhibitors of electron transfer chain of mitochondria or oligomycin, an inhibitor of ATP synthesis. Treatment of rho+ cells with 100 microM MEN induced apoptosis, which reached the maximum at 6 h, and was followed by an abrupt decrease thereafter, while necrotic cells (NC) increased continuously when they were judged by Annexin V and PI double staining. On the other hand, MEN induced apoptotic and necrotic changes much faster in rho0 cells compared to rho+ cells. The frequency to find apoptotic cells (AP) in the former cells was distinctly smaller than that to find NC judged by Annexin V and PI double staining. Electron microscopically, a major population of rho0 cells treated with MEN for 6 h consisted of intermediate cells, and a small number of AP co-existed. At 9 h of the treatment intermediate cells were exclusively seen, and AP were hardly detected. When parental rho+ cells were treated with MEN in the presence of oligomycin or oligomycin plus antimycin A both apoptotic and necrotic changes of the cells were distinctly accelerated. The intracellular level of superoxide in rho0 cells continuously increased after the MEN treatment, whereas that of ATP remained distinctly low before and after the MEN treatment compared to that in rho+ cells. These data suggest that the intracellular level of superoxide may be a key factor controlling the switch from apoptosis to necrosis.     

Multifaceted Analysis of IL-23A- and/or EBI3-Including Cytokines Produced by Psoriatic Keratinocytes

Interleukin (IL) 23 (p19/p40) plays a critical role in the pathogenesis of psoriasis and is upregulated in psoriasis skin lesions. In clinical practice, anti-IL-23Ap19 antibodies are highly effective against psoriasis. IL-39 (p19/ Epstein-Barr virus-induced (EBI) 3), a newly discovered cytokine in 2015, shares the p19 subunit with IL-23. Anti-IL-23Ap19 antibodies may bind to IL-39; also, the cytokine may contribute to the pathogenesis of psoriasis. To investigate IL23Ap19- and/or EBI3-including cytokines in psoriatic keratinocytes, we analyzed IL-23Ap19 and EBI3 expressions in psoriasis skin lesions, using immunohistochemistry and normal human epidermal keratinocytes (NHEKs) stimulated with inflammatory cytokines, using quantitative real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and liquid chromatography-electrospray tandem mass spectrometry (LC-Ms/Ms). Immunohistochemical analysis showed that IL-23Ap19 and EBI3 expressions were upregulated in the psoriasis skin lesions. In vitro, these expressions were synergistically induced by the triple combination of tumor necrosis factor (TNF)-α, IL-17A, and interferon (IFN)-γ, and suppressed by dexamethasone, vitamin D3, and acitretin. In ELISA and LC-Ms/Ms analyses, keratinocyte-derived IL-23Ap19 and EBI3, but not heterodimeric forms, were detected with humanized anti-IL-23Ap19 monoclonal antibodies, tildrakizumab, and anti-EBI3 antibodies, respectively. Psoriatic keratinocytes may express IL-23Ap19 and EBI3 proteins in a monomer or homopolymer, such as homodimer or homotrimer.