Solid-State Characterization and Interconversion of Recrystallized Amodiaquine Dihydrochloride in Aliphatic Monohydric Alcohols

Amodiaquine dihydrochloride monohydrate (AQ-DM) was obtained by recrystallizing amodiaquine dihydrochloride dihydrate (AQ-DD) in methanol, ethanol, and n-propanol. Solid-state characterization of AQ-DD and AQ-DM was performed using X-ray powder diffractometry, Fourier transform infrared spectroscopy, thermogravimetry, and differential scanning calorimetry. All recrystallized samples were identified as AQ-DM. Crystal habits of AQ-DD and AQ-DM were shown to be needle-like and rhombohedral crystals, respectively. When AQ-DD and AQ-DM were exposed to various relative humidity in dynamic vapor sorption apparatus, no solid-state interconversion was observed. However, AQ-DM showed higher solubility than AQ-DD when exposed to bulk water during solubility study, while excess AQ-DM was directly transformed back to a more stable AQ-DD structure. Heating AQ-DM sample to temperatures ≥190°C induced initial change to metastable amorphous form (AQ-DA) which was rapidly recrystallized to AQ-DD upon ≥80%RH moisture exposure. AQ-DD was able to be recrystallized in alcohols (C1-C3) as AQ-DM solid-state structure. In summary, AQ-DM was shown to have different solubility, moisture and temperature stability, and interconversion pathways when compared to AQ-DD. Thus, when AQ-DM was selected for any pharmaceutical applications, these critical transformation and property differences should be observed and closely monitored.     

The Effect of Freezing on the Radiation Sensitivity of Bacterial Spores

S ummary : Bacillus pumilus spores, irradiated under aerobic conditions, were inactivated exponentially at the same rate whether they were at room temperature (10–13°) in phosphate buffer or at -79° in phosphate buffer or in heart infusion broth.
Clostridium welchii spores were irradiated in Robertson's cooked meat medium under anaerobic conditions. With unheated spores, and those subjected to a heat shock before irradiation, the inactivation rate was the same at room temperature and -79°. The same applied to spores heat shocked after irradiation for doses up to 450 Krads, but above this dose level the spores irradiated frozen were more sensitive.
The effect of the heat shock, whether applied before or after irradiation, was to increase the number of survivors, and the proportionate increase appeared to vary with dose.     

光频微波对黄曲霉的杀灭试验

黄曲霉是污染粮食、食品、中药材和烟丝的常见霉菌。由于黄曲霉的产物黄曲霉毒素具有很强的致癌作用。因此 ,从这些食品或物品中消除黄曲霉可减少甚至消除黄曲霉毒素的危害。报告了微波辐射杀灭烟丝中黄曲霉的效果。光频微波对烟丝上的黄曲霉菌具有良好的杀灭作用 ,微波辐射 30s后菌落数明显减少 ,经 4 5s作用后可完全杀灭黄曲霉的细胞 (包括菌丝和孢子 )。应用光频微波辐射杀灭黄曲霉具有经济、方便和高效的优点 ,既可以用于大规模工业生产 ,亦可在家庭生活中使用。     

Effect of Microwave Radiation on Immobilization of Heavy Metals in Sediment Sludge

In order to evaluate the effect of microwave radiation on immobilization of heavy metals (Cu ^{2 +} , Cr ^{6 +} , Zn ^{2 +} and Pb ^{2 +} ) in sediment sludge, leaching tests were run under different test conditions to compare microwave radiation with conventional blast heating and drying process for their effectiveness in immobilizing heavy metals within sediment sludge. Experimental results indicate that microwave radiation can decrease the concentration of heavy metals in leachate by 63% ～ 70% more than conventional blast heating and drying process in an aclinic shake leaching test. Under the same simulated natural water conditions, the concentration of heavy metals in the leachate using microwave radiation is well below the concentration of heavy metals in leachate using conventional blast heating and drying process. It is therefore concluded that microwave radiation is much more effective than conventional blast heating and drying process in immobilizing heavy metals in sediment sludge.     

The Effect of Tuning Cold Plasma Composition on Glioblastoma Cell Viability

Previous research in cold atmospheric plasma (CAP) and cancer cell interaction has repeatedly proven that the cold plasma induced cell death. It is postulated that the reactive oxygen species (ROS) and reactive nitrogen species (RNS) play a major role in the CAP cancer therapy. In this paper, we seek to determine a mechanism of CAP therapy on glioblastoma cells (U87) through an understanding of the composition of the plasma, including treatment time, voltage, flow-rate and plasma-gas composition. In order to determine the threshold of plasma treatment on U87, normal human astrocytes (E6/E7) were used as the comparison cell line. Our data showed that the 30 sec plasma treatment caused 3-fold cell death in the U87 cells compared to the E6/E7 cells. All the other compositions of cold plasma were performed based on this result: plasma treatment time was maintained at 30 s per well while other plasma characteristics such as voltage, flow rate of source gas, and composition of source gas were changed one at a time to vary the intensity of the reactive species composition in the plasma jet, which may finally have various effect on cells reflected by cell viability. We defined a term “plasma dosage” to summarize the relationship of all the characteristics and cell viability.     

微波辐射对PC12细胞Raf/MEK/ERK信号通路相关分子表达的影响

体外培养PC12细胞,将其诱导分化为神经元后,建立微波辐射细胞模型,采用免疫印迹技术和图像分析技术研究微波辐射后Raf/MEK/ERK信号通路相关分子的动态表达变化规律,进一步探讨微波辐射损伤的分子机制。结果发现,微波辐射后6h～3d,假辐射组和辐射组PC12细胞中Raf-1、ERK表达均呈先增加后减少趋势,两组差别不显著,但辐射组Raf-1、ERK和CREB的磷酸化水平均较假辐射组明显升高,表明Raf/MEK/ERK信号通路活化增强可能是微波辐射致神经细胞损伤的重要机制。     

Differential Damage in Bacterial Cells by Microwave Radiation on the Basis of Cell Wall Structure

Microwave radiation in Escherichia coli and Bacillus subtilis cell suspensions resulted in a dramatic reduction of the viable counts as well as increases in the amounts of DNA and protein released from the cells according to the increase of the final temperature of the cell suspensions. However, no significant reduction of cell density was observed in either cell suspension. It is believed that this is due to the fact that most of the bacterial cells inactivated by microwave radiation remained unlysed. Scanning electron microscopy of the microwave-heated cells revealed severe damage on the surface of most E. coli cells, yet there was no significant change observed in the B. subtilis cells. Microwave-injured E. coli cells were easily lysed in the presence of sodium dodecyl sulfate (SDS), yet B. subtilis cells were resistant to SDS.     

Effect of Genes Controlling Radiation Sensitivity on Chemically Induced Mutations in SACCHAROMYCES CEREVISIAE

The effect of 16 different genes (rad) conferring radiation sensitivity on chemically induced reversion in the yeast Saccharomyces cerevisiae was determined. The site of reversion used was a well-defined chain initiation mutant mapping in the structural gene coding for iso-1-cytochrome c. High doses of EMS and HNO₂ resulted in decreased reversion of cyc1–131 in rad6, rad9 and rad15 strains compared to the normal RAD+ strains. In addition, rad52 greatly decreased EMS reversion of cyc1–131 but had not effect on HNO ₂-induced reversion; rad18, on the other hand, increased HNO ₂-induced reversion but did not alter EMS-induced reversion. When NQO was used as the mutagen, every rad gene tested, except for rad14 , had an effect on reversion; rad6, rad9, rad15, rad17, rad18, rad22, rev1, rev2 and rev3 lowered NQO reversion while rad1, rad2, rad3, rad4, rad10, rad12 and rad16 increased it compared to the RAD+ strain. The effect of rad genes on chemical mutagenesis is discussed in terms of their effect on UV mutagenesis. It is concluded that although the nature of the repair pathways may differ for UV- and chemically-induced mutations in yeast, a functional repair system is required for the induction of mutation by the chemical agents NQO, EMS and HNO₂.     

肺腺癌细胞中STAT3表达对细胞生长及药物敏感性的影响

目的:探讨STAT3表达变化对细胞生长及化疗药物敏感性的影响.方法:采用AG490处理细胞、SOCS3基因转染A549细胞后.Western blot检测STAT3蛋白酪氨酸磷酸化水平变化;MTT法检测细胞增殖情况;不同浓度泰素处理细胞后观察细胞对药物的敏感性.结果:AG490处理细胞、SOCS3基因转染细胞后,Western blot证实其能显著抑制STAT3蛋白酪氨酸磷酸化水平(P<0.01);MTT法结果示细胞增殖明显受到抑制;细胞对泰素敏感性显著增高.结论:STAT3能促进细胞增殖,AG490、SOCS3能显著抑制A549细胞中STAT3蛋白的活性,从而抑制A549细胞生长并增加其对化疗药物的敏感性.     

增强UV-B辐射对拟南芥叶肉细胞蛋白的影响

采用不同剂量的UV-B辐射处理4周龄的野生型拟南芥幼苗(Columbia-0),分别采用丙酮沉淀法和TCA-丙酮法提取其叶肉细胞中的蛋白质,进而研究分析拟南芥叶肉细胞中蛋白质的含量与组成对不同强度UV-B辐射的响应。结果显示,两种方法相比较,TCA-丙酮法所提取得到的蛋白含量相对较多,更适合于分析增强UV-B辐射对拟南芥叶肉细胞蛋白质的影响;而两种方法所提取得到的蛋白质含量的变化趋势相同,随着UV-B辐射剂量的增加,蛋白质含量呈先增加后减少的趋势,B₂组达到了最大。此外,蛋白条带的数目和表达量也都发生了显著变化,同样也是以中剂量处理组（B₂组）变化最为明显,既有新增条带,又有消失条带。这可能是由于拟南芥在受到低剂量的UV-B辐射时,可以激活自身一些抗性基因的表达而诱导产生抗性蛋白,进而抵御UV-B的伤害;而当受到高剂量的UV-B辐射时,损伤自身的蛋白质合成途径,影响蛋白的合成。     

Influence of Plasma Unsteadiness on the Spectrum and Shape of Microwave Pulses in a Plasma Relativistic Microwave Amplifier

Dependence of the shape of a microwave pulse in a plasma relativistic microwave amplifier (PRMA) on the initial plasma electron density in the system is detected experimentally. Depending on the plasma density, fast disruption of amplification, stable operation of the amplifier during the relativistic electron beam (REB) pulse, and its delayed actuation can take place. A reduction in the output signal frequency relative to the input frequency is observed experimentally. The change in the shape of the microwave signal and the reduction in its frequency are explained by a decrease in the plasma density in the system. The dynamics of the plasma density during the REB pulse is determined qualitatively from the experimental data by using the linear theory of a PRMA with a thin-wall hollow electron beam. The processes in a PRMA are analyzed by means of the KARAT particle-in-cell code. It is shown that REB injection is accompanied by an increase in the mean energy of plasma electrons and a significant decrease in their density.     

The Effect of Early Application of a Combined Therapy of Bone Marrow Mesenchymal Stem Cells and Platelet-Rich Plasma on Blood and Bone Parameters in Ovariectomized Rats

Journal of Evolutionary Biochemistry and Physiology - Osteoporosis is a common bone disorder with marked morbidity and mortality that occurs frequently in women after menopause. Inadequacy of...     

TIP-1 Translocation onto the Cell Plasma Membrane Is a Molecular Biomarker of Tumor Response to Ionizing Radiation

Background

Tumor response to treatment has been generally assessed with anatomic and functional imaging. Recent development of in vivo molecular and cellular imaging showed promise in time-efficient assessment of the therapeutic efficacy of a prescribed regimen. Currently, the in vivo molecular imaging is limited with shortage of biomarkers and probes with sound biological relevance. We have previously shown in tumor-bearing mice that a hexapeptide (HVGGSSV) demonstrated potentials as a molecular imaging probe to distinguish the tumors responding to ionizing radiation (IR) and/or tyrosine kinase inhibitor treatment from those of non-responding tumors.

Methodology/Principal Findings

In this study we have studied biological basis of the HVGGSSV peptide binding within the irradiated tumors by use of tumor-bearing mice and cultured cancer cells. The results indicated that Tax interacting protein 1 (TIP-1, also known as Tax1BP3) is a molecular target that enables the selective binding of the HVGGSSV peptide within irradiated xenograft tumors. Optical imaging and immunohistochemical staining indicated that a TIP-1 specific antibody demonstrated similar biodistribution as the peptide in tumor-bearing mice. The TIP-1 antibody blocked the peptide from binding within irradiated tumors. Studies on both of human and mouse lung cancer cells showed that the intracellular TIP-1 relocated to the plasma membrane surface within the first few hours after exposure to IR and before the onset of treatment associated apoptosis and cell death. TIP-1 relocation onto the cell surface is associated with the reduced proliferation and the enhanced susceptibility to the subsequent IR treatment.

Conclusions/Significance

This study by use of tumor-bearing mice and cultured cancer cells suggested that imaging of the radiation-inducible TIP-1 translocation onto the cancer cell surface may predict the tumor responsiveness to radiation in a time-efficient manner and thus tailor radiotherapy of cancer.     

Mutants of Staphylococcus aureus with Increased Sensitivity to Ultraviolet Radiation

Nitrosoguanidine (NG) mutagenesis of Staphylococcus aureus resulted in the isolation of eight mutants exhibiting 3 to 28 times greater sensitivity to ultraviolet (UV) radiation. These mutants were further characterized by their ability to repair UV-irradiated bacteriophage, to act as recipients in the transduction of antibiotic resistance, and their sensitivity to NG. Based on the available data, six of these mutants are reduced in their ability to perform host-cell reactivation. One of the remaining two mutants may be deficient in post-replication repair.     

The Effects of Low-Intensity Millimeter-Wavelength Radiation and Electromagnetic Shielding on Pain Sensitivity in Rats

Here, we studied changes in pain sensitivity in rats subjected to low-intensity millimeter-wavelength electromagnetic radiation (EMR MM) of 7.1 mm and 0.1 mW/cm² in the occipital-collar region with daily exposure of 30 min over 21 days. As well, this radiation was combined with moderate electromagnetic shielding (EMS) which had the following parameters. The shielding coefficients of the constant component of the magnetic field along the vertical and horizontal constituents were 4.4- and 20-fold, respectively, with an exposure of 22 h/day over 21 days. The pain sensitivity was estimated with algometric tests, that is, the hot plate, flick-tail, and algesimeter-pincher tests; these allowed observation of the pain impulse at different regulatory levels. The algological effects of both individual and combined EMR MM and EMS were demonstrated. It was shown that EMR MM has an antinociceptive property when combined with EMS, as well as a modulation effect caused by shielding during hyperalgesia. At the same time, shielding reduces the antinociceptive effect of EMR MM.

     

A Study of the Effect of Terahertz Electromagnetic Radiation on Microbial Cell Viability

Biophysics - Abstract—The effect of pulsed terahertz radiation at a wavelength of 66 μm, a pulse duration of 100 ns, and a pulse energy of 200 mJ on a suspension of microbial cells was...