Interaction of platinum agents, cisplatin, carboplatin and oxaliplatin against albumin in vivo rats and in vitro study using inductively coupled plasma-mass spectrometory.

The protein binding rates (PBR) of platinum-containing agents cisplatin (CDDP), carboplatin (CBDCA) and oxaliplatin (L-OHP) have been reported as 98%, 25-50% and 98%, respectively. To investigate the protein-binding properties of albumin with cisplatin, carboplatin and oxaliplatin, inductively coupled plasma mass spectrometry (ICP-MS) was used to measure their plasma concentration in rats over time. The study also examined the effects of cisplatin, carboplatin and oxaliplatin-binding on albumin in vitro, using CD spectrometry and native-polyacrylamide gel electrophoresis (native PAGE). The ratios of PBR to irreversible PBR, of cisplatin and oxaliplatin were 98%:98% and 90%:87%, respectively, indicating a higher affinity for irreversible binding with albumin. That of carboplatin was 25%:10%, indicating 60-70% reversible binding with albumin. The plasma protein binding rate concentrations of cisplatin, carboplatin and oxaliplatin after in vivo administration were 96%, 15% and 80%, respectively. The CD spectrometry of albumin was unaffected by cisplatin, carboplatin and oxaliplatin binding. Though similar protein binding rates were observed with oxaliplatin and cisplatin, oxaliplatin had a higher mobility rate during PAGE. It was confirmed that the binding of cisplatin and oxaliplatin with albumin affected its electric charge but not the structure. In conclusion, cisplatin and oxaliplatin bind irreversibly with albumin in plasma and may irreversibly interact with tissue protein and/or DNA. The difficulties involved with predicting the tissue concentrations of cisplatin and oxaliplatin from their plasma concentration inhibits their therapeutic drug monitoring. On the contrary, carboplatin, like some generic drugs, reversibly binds to plasma proteins. It is, therefore, possible to conduct therapeutic drug monitoring for carboplatin.

Performance and efficiency of removal of pharmaceutical compounds from hospital wastewater by lab-scale biological treatment system.

The fate of pharmaceuticals after discharged from hospital into wastewater was clarified experimentally by using a new lab-scale conventional activated sludge (CAS) treatment reactor. The 43 target compounds belong to nine therapeutic classes (antivirals, antibacterials, anticancer drugs, psychotropics, antihypertensives, analgesic-antipyretics, contrast media, herbal medicines, and phytoestrogens) were selected with inclusion of 16 newly estimated compounds. The efficiency of the present reactor was estimated by comparing the reaction rate constant of the solid-water partition coefficients (log Kd) between liquid and solid samples and half-life during 48-h experiment obtained by using hospital effluents with those obtained by using STP wastewater. The results that no significant difference in removal efficiency was observed between both water samples (P > 0.05) indicate high reliability of the present lab-scale reactor. The actual rates of removal when hospital effluent was applied varied widely (mean, 59 ± 40%) independent of type of the pharmaceuticals. More than 90% of 17 compounds were removed after 8 h of treatment. However, the values for psychotropics (mean, 19 ± 26%) and contrast media (mean, 24 ± 17%) were generally low, indicating high stability. The log Kd values ranged from 1.3 to 4.8. Notably, clarithromycin, acridine, and glycitein could be removed in both liquid and solid phases. The dominant removal mechanisms were found to be different for individual pharmaceutical. These results suggest the effectiveness of introduction of the lab-scale biological treatment system for development of a new solution for discharge of pharmaceuticals from hospital.

[Bioinorganic Chemistry of Iron].

　The X-ray crystallographic analysis of the single-crystal mugineic acid-Cu(II) complex showed that mugineic acid acts as a hexadentate ligand. Mugineic acid, a typical phytosiderophore, shows a marked stimulating effect on 59Fe-uptake and chlorophyll synthesis in rice plants. A salient feature is the higher reduction potential of the mugineic acid-Fe(III) complex than those of bacterial siderophores. X-ray diffraction study of the structurally analogous Co(III) complex of the mugineic acid-Fe(III) complex demonstrates that the azetidine nitrogen and secondary amine nitrogen, and both terminal carboxylate oxygens, coordinate as basal planar donors, and the hydroxyl oxygen and intermediate carboxylate oxygen bind as axial donors in a nearly octahedral configuration. The iron-transport mechanism in gramineous plants appears to involve the excretion of mugineic acid from the roots, which aids Fe(III)-solubilization and reduction of Fe(III) to Fe(II). Manganese peroxidase (MnP) is a component of the lignin degradation system of the basidiomycetous fungus, Phanerochaete chrysosporium. To elucidate the heme environment of this novel Mn(II)-dependent extracellular enzyme, we studied its ESR and resonance Raman spectroscopic properties. Consequently, it is most likely that the heme environment of MnP resembles that of cytochrome c peroxidase. In addition, degradation methods using basidiomycetous fungi or Fe3+-H2O2 mixed reagent were developed for dioxins and polychlorinated biphenyls. The complete amino acid sequences of respective [2Fe-2S] ferredoxins were determined and compared with those of other higher plants. Finally, the toxic effects of iron on human health and the development of novel antibacterial drugs capable of inhibiting the iron transport system of Vibrio vulnificus are described.

Distribution of six anticancer drugs and a variety of other pharmaceuticals, and their sorption onto sediments, in an urban Japanese river.

The distributions of 31 pharmaceuticals grouped into nine therapeutic classes, including six anticancer drugs, were investigated in the waters and sediments of an urban river in Japan. The coefficients of sorption (logK d) to the river sediments were also determined from the results of a field survey and laboratory-scale experiment. Three anticancer drugs-bicalutamide, doxifluridine, and tamoxifen-were detected in the river sediments at maximum concentrations of 391, 392, and 250 ng/kg, respectively. In addition, the transformation products of psychotropic carbamazepine (2-hydroxy carbamazepine, acridine, and acridone) were detected in the range of 108 ng/kg (2-hydroxy carbamazepine) to 2365 ng/kg (acridine), and the phytoestrogen glycitein was detected in the range of N.D. to 821 ng/kg. The logK d values of the targeted pharmaceuticals in river sediments in the field survey ranged from 0.5 (theophylline) to 3.3 (azithromycin). These results were in accord with those of the laboratory-scale sorption experiment. To the best of our knowledge, this is the first report of the detection of the anticancer drugs bicalutamide and tamoxifen, the transformation products of carbamazepine (2-hydroxy carbamazepine, acridine, and acridone), and the phytoestrogen genistein in river sediments.

A Novel Analytical Method of Cisplatin Using the HPLC with a Naphthylethyl Group Bonded with Silica Gel (πNAP) Column.

Cisplatin is the most widely used anticancer drug in the world. Mono-chloro and none-chloro complexes of cisplatin may be believed to be the activated compounds. The separation of these compounds using octa decyl silyl column or aminopropylsilyl silica gel column is difficult because of high-reactivity and structural similarity. In this study, cisplatin, hydroxo complexes, and OH-dimer were determined by HPLC using a naphthylethyl group bonded with silica gel (πNAP) column. The analytical conditions of HPLC were as follows: analytical column, πNAP column; wave length, 225 nm; column temperature, 40°C; mobile phase, 0.1 M sodium perchlorate, acetonitrile, and perchloric acid (290 : 10 : 3), flow rate, 1.0 mL/min. Sample (20 µL) was injected onto the HPLC system. Retention time of cisplatin, mono-chloride, OH-dimer, and none-chloride was 3.2, 3.4, 3.6, and, 4.3-6.6 min, respectively. Measurable ranges with this method were 1×10-5 to 4×10-3 M for cisplatin. Correlation coefficient of the calibration curves of cisplatin was 0.999 (p<0.01). The within- and between-day variations of coefficient of variation (CV) were 5% or lower. In this study, injectable formulations in physiological saline solution, water for injection, 5% glucose solution, and 7% sodium bicarbonate precisely were measured the stability and compositional changes upon mixing by πNAP column rather than C18 column. We successfully determined cisplatin, hydroxo complexes, and OH-dimer by HPLC using a πNAP column. Thus the measurement of cisplatin (cis-diamminedichloro-platinum(II), cis-[PtCl2(NH3)2]) (CDDP) should be done using a πNAP column rather than a C18 column or aminopropylsilyl silica gel column.

Detection of pharmaceuticals and phytochemicals together with their metabolites in hospital effluents in Japan, and their contribution to sewage treatment plant influents.

The occurrence of 41 pharmaceuticals and phytochemicals (PPs) including their metabolites was surveyed in hospital effluent in an urban area of Japan. A detailed survey of sewage treatment plant (STP) influent and effluent, and river water was also conducted. Finally, mass balances with mass fluxes of the target PPs through the water flow were evaluated and the degree of contribution of hospital effluent to the environmental discharge was estimated. The results indicate that 38 compounds were detectable in hospital effluent over a wide concentration range from ng/L to µg/L, with a maximum of 92µg/L. The contributions of PPs in the hospital effluent to STP influent varied widely from <0.1% to 14.8%. Although almost all of the remaining components could be removed below 1.0ng/L at STPs by the addition of ozone treatment, a number of PPs still remained above 10ng/L in STP effluent. These findings suggest the importance of applying highly developed treatments to hospital effluents and at STPs in the future to reduce the environmental risks posed by PPs. To our knowledge, this is the first demonstration of the presence of two conjugated metabolites of acetaminophen, acetaminophen glucuronide and acetaminophen sulfate, as well as of loxoprofen and loxoprofen alcohol, in hospital effluent, STP, and river waters.

Occurrence and fate of selected anticancer, antimicrobial, and psychotropic pharmaceuticals in an urban river in a subcatchment of the Yodo River basin, Japan.

Pollution status of six anticancer agents in the river water and effluents of sewage treatment plants (STPs) in Japan was surveyed with comparative analysis of the levels of four microbial and one psychotropic pharmaceuticals widely used for therapeutic medication. The area of survey is located in the Kanzaki-Ai River basin which is a major subcatchment of the Yodo River basin and is centered on a highly populated area that includes the middle and downstream reaches of the Yodo River. Selected cancer agents were bicalutamide, capecitabine, cyclophosphamide, doxifluridine, tamoxifen, and tegafur. A combination of strong anion solid-phase extraction cartridge under pH 11 for adsorption and optimization of liquid chromatography-tandem mass spectroscopy (LC-MS/MS) system was necessary to ensure high recovery rates (63-124% for river water and 52-115% for STP effluent). The year-round survey of these compounds in four seasons showed that all anticancer compounds were detected at median concentrations ranged from not detected to 32 ng/L in the river water and from not detected to 245 ng/L in the effluents of sewage treatment plants not using ozonation. In the case of bicalutamide (an active antiandrogen used to treat prostate cancer), the maximum concentration detected was 254 ng/L in river water and 1032 ng/L in non-ozonated sewage treatment plant effluents. Based on the mass balance, sewage treatment plants were the primary sources of anticancer compounds as well as the other pharmaceuticals in the river, and the attenuation effect of the river water was small. Ozonation at sewage treatment plants was effective in removing these compounds. To the best of our knowledge, this study is the first to report the existence of bicalutamide, doxifluridine, and tegafur in the river environment.

Second- and higher-order structural changes of DNA induced by antitumor-active tetrazolato-bridged dinuclear platinum(II) complexes with different types of 5-substituent.

Here, we used circular dichroism (CD) and fluorescence microscopy (FM) to examine the interactions of a series of antitumor-active tetrazolato-bridged dinuclear platinum(II) complexes, [{cis-Pt(NH3)2}2(µ-OH)(µ-5-R-tetrazolato-N2,N3)](n+) (R=CH3 (1), C6H5 (2), CH2COOCH2CH3 (3), CH2COO(-) (4), n=2 (1-3) or 1 (4)), which are derivatives of [{cis-Pt(NH3)2}2(µ-OH)(µ-tetrazolato-N2,N3)](2+) (5-H-Y), with DNA to elucidate the influence of these interactions on the secondary or higher-order structure of DNA and reveal the mechanism of action. The CD study showed that three derivatives, 1-3, with a double-positive charge altered the secondary structures of calf thymus DNA but that 4, the only complex with a single positive charge, induced almost no change, implying that the B- to C-form conformational change is influenced by ionic attraction. Unexpectedly, single-molecule observations with FM revealed that 4 changed the higher-order structure of T4 DNA into the compact-globule state most efficiently, at the lowest concentration, which was nearly equal to that of 5-H-Y. These contradictory results suggest that secondary structural changes are not necessarily linked to higher-order ones, and that the non-coordinative interaction could be divided into two distinct interactions: (1) ionic attraction and (2) hydrogen bonding and/or van der Waals contact. The relationship between diffusion-controlled non-coordinative DNA interactions and cytotoxicities is also discussed.

Adenosine thiamine triphosphate (AThTP) inhibits poly(ADP-ribose) polymerase-1 (PARP-1) activity.

Overactivation of poly(ADP-ribose) polymerase-1 (PARP-1) has been demonstrated to result in various stress-related diseases, including diabetes mellitus. Deficiency of cellular nicotinamide adenine dinucleotide (NAD(+)) content, consumed by PARP-1 to add ADP-ribose moieties onto target proteins, contributes to pathophysiological conditions. Adenosine thiamine triphosphate (AThTP) exists in small amounts in mammals; however, the function(s) of this metabolite remains unresolved. The structure of AThTP resembles NAD(+). Recent experimental studies demonstrate beneficial impacts of high-dose thiamine treatment of diabetic complications. These findings have led us to hypothesize that AThTP may modulate the activity of PARP-1. We have chemically synthesized AThTP and evaluated the effect of AThTP on recombinant PARP-1 enzyme activity. AThTP inhibited the PARP-1 activity at 10 µM, and a structural model of the PARP-1-AThTP complex highlighted the AThTP binding site. The results provide new insights into the pharmacological importance of AThTP as an inhibitor of PARP-1.

Optochiasmal arachnoiditis following cotton wrapping of anterior communicating artery aneurysm treated by surgical removal of granuloma.

We report the case of a 50 year old female who presented with visual disturbance due to optochiasmal arachnoiditis and foreign body granuloma 9 months after cotton wrapping for ruptured anterior communicating artery (AcomA) aneurysm. Magnetic resonance imaging (MRI) revealed enhanced mass lesion around AcomA complex and hyperintense signal on optic chiasm and right optic tract by fluid-attenuated inversion recovery image. Despite the repeated steroid pulse therapy, she deteriorated and MRI showed expansion of the granulomatous lesion over 5 months. Surgical removal of foreign body granuloma resulted in marked improvement of visual disturbance as well as of the MRI findings. We conclude that the use of cotton sheet close to the optic nerve should be avoided, and that surgical removal of the granuloma would be the optimal choice especially for the patient in whom steroid therapy fails to improve clinical symptoms.

[Traumatic vertebral arteriovenous fistula caused by an injury due to penetration by pieces of glass: case report].

We reported a case of a 79-year-old male with traumatic vertebral arteriovenous fistula. The patient was admitted with hemorrhagic shock due to arterial bleeding caused by a penetrating injury of the neck. Cervical CT showed free air at the level of the lamina of C1. Injury of the vertebral artery was suspected. The right vertebral angiogram showed an arteriovenous fistula between the V3 portion of the right vertebral artery and the suboccipital venous plexus with retrograde intracranial venous drainage. The patient underwent endovascular treatment of the parent vertebral artery occlusion, which successfully obliterated the arteriovenous fistula.