Elastic differential cross sections for C4F6 isomers in the 1.5-200 eV energy electron impact: similarities with six fluorine containing molecules and evidence of F-atom like scattering.

We report absolute elastic differential cross sections for electron interactions with the C4F6 isomers, hexafluoro-1,3-butadiene (1,3-C4F6), hexafluoro-2-butyne (2-C4F6), and hexafluorocyclobutene (c-C4F6). The incident electron energy range is 1.5-200 eV, and the scattered electron angular range for the differential measurements varies from 15° to 150°. In all cases the absolute scale of the differential cross section was set using the relative flow technique, with helium as the reference species. Atomic-like behaviour in these scattering systems is shown here for the first time, and is further investigated by comparing the elastic cross sections for the C4F6 isomers with other fluorinated molecules, such as SF6 and CnF6 (n = 2, 3, and 6). We note that for all the six-F containing molecules, the scattering process for electron energies above 30 eV is indistinguishable. Finally, we report results for calculations of elastic differential cross sections for electron scattering from each of these isomers, within an optical potential method and assuming a screened corrected independent atom representation. The level of agreement between these calculations and our measurements is found to be quite remarkable in all cases.

An automated rapid detection system using the quenching probe method for detecting interleukin 28B and inosine triphosphatase single nucleotide polymorphisms in chronic hepatitis C.

Single nucleotide polymorphisms (SNPs) in the interleukin 28B gene (IL28B) are good pretreatment predictors of anti-hepatitis C virus (HCV) therapy with interferon. SNPs of the inosine triphosphatase (ITPA) gene are associated with reduced haemoglobin levels during treatment with ribavirin. The i-densy™ (Arkray, Inc.), which is based on the quenching probe (QP) method, automatically detects target genes in blood samples by fluorescence quenching within 100 min. Using a QP and primer set, a gene amplification response is generated that can quickly and easily detect a specific gene's arrangement by fluorometry. The present study was conducted to compare the utility of i-densy (QP method) with that of conventional direct sequencing (DS) for detecting SNPs in the IL28B and ITPA genes in chronic hepatitis C patients. Between June 2011 and January 2012, 73 consecutive patients underwent genotyping of IL28B, and 54 patients underwent genotyping of ITPA. All of the patients were seropositive for HCV-RNA. The IL28B and ITPA genotypes were tested for bi-allelic polymorphisms in rs8099917 (T/T, T/G and G/G; minor allele, G) and rs1127354 (C/C, C/A and A/A; minor allele, A), respectively. The results obtained with the QP method were identical to those obtained with the conventional DS method. The frequency of the IL28B genotypes TT, GT and GG were 74%, 24.7% and 1.4%, respectively, and those of the ITPA genotypes CC, AC and AA were 68.5%, 29.6% and 1.9%, respectively. These results indicate that the i-densy using the QP method can automatically, quickly and easily identify genotypes of IL28B and ITPA.

Electronic excitation to singlet states of 1,3-C4F6, c-C4F6 and 2-C4F6 by electron impact--electron energy-loss spectroscopy and ab initio calculations.

We report on the first measurements of the electron impact electronic excitation cross sections for C(4)F(6) isomers, hexafluoro-1,3-butadiene (1,3-C(4)F(6)), hexafluorocyclobutene (c-C(4)F(6)), and hexafluoro-2-butyne (2-C(4)F(6)), measured at 100 eV, 3° scattering angle, while sweeping the energy loss over the range 2.0-15.0 eV. Under these experimental conditions, optically allowed transitions are favored. The electronic state spectroscopy has been investigated and the assignments supported by quantum chemical calculations. The n = 3 members of the Rydberg series have been assigned converging to the lowest ionization energy limits of the C(4)F(6) isomers and classified according to the magnitude of the quantum defects (δ).

Pharmacological activity and structural analysis of a benzamide (TKS159) and its optical isomers in an in vitro study and in an in vivo study in mice.

We previously conducted an in vitro study of 4-amino-5-chloro-2-methoxy-N-(1-ethyl-2-hydroxymethyl-4-pyrrolidinyl)benzamide (2S,4S)-(1, TKS159) and its three optical isomers (2S,4R)-(2), (2R,4S)-(3) and (2R,4R)-(4) with respect to their binding ability to the 5-HT(4) receptors, as well as an in vivo study on their gastric emptying-accelerating ability in rats. Consequently, we reported that steric configuration at positions 2 and 4 of the pyrrolidine ring is important in determining their pharmacological activity. The optical isomer (2R,4S)-(3) exhibited the most potent binding ability. However, the compound (2S,4S)-(1, TKS159) exhibited the most potent gastric emptying-accelerating ability in rats. A difference was thus found between binding ability and gastric emptying-accelerating ability in rats. Therefore, we conducted an in vitro study of TKS159 (1) and its three optical isomers to examine their agonistic activity on the 5-HT(4) receptors, as well as an in vivo study in mice to examine their gastric emptying-accelerating ability. Consequently, a tendency for correlation was found between the activity and the ability. TKS159 (1) exhibited the most potent pharmacological activity, well reflecting the results from the previous in vivo study in rats. Furthermore, the present in vitro and in vivo studies reverified the importance of steric configuration at positions 2 and 4 of the pyrrolidine ring. In addition, we also made an X-ray crystallographic analysis of the optical isomer (2R,4S)-(3), which has the S-configuration at position 4 similar to TKS159 (1), and discussed molecular structures in conjunction with the previously reported results from the X-ray crystallographic analysis of TKS159 (1).

alpha-Lipoic acid attenuates x-irradiation-induced oxidative stress in mice.

The development of nontoxic but effective radioprotectors is needed because of the increasing risk of human exposure to ionizing radiation. We have reported that alpha-lipoic acid confers considerable radio-protective effect in mouse tissues when given prior to x-irradiation. In the present study, alpha-lipoic acid supplementation prior to x-irradiation with 4 and 6 Gy significantly inhibited the radiation-induced decline in total antioxidant capacity (TAC) of plasma. Radiation-induced decline in non-protein sulfhydryl content (NPSH) of different tissues, namely, brain, liver, spleen, kidney, and testis, was also ameliorated significantly at both 4 and 6 Gy doses. Maximal augmentation of radiation-induced protein carbonyl content was observed in spleen followed by brain, kidney, testis, and liver. Maximal protection in terms of carbonyl content was observed in spleen (116%) at 6 Gy dose, and minimal protection was found in liver (22.94%) at 4 Gy dose. Maximal increase in MDA (malondialdehyde) content was observed in brain, followed by testis, spleen, kidney, and liver. Protection by alpha-lipoic acid pretreatment in terms of MDA content was maximal in brain (51.67%) and minimal in spleen. The findings support the idea that alpha-lipoic acid is a free-radical scavenger and a potent antioxidant.

Effects of glycine betaine on bone marrow death and intestinal damage by gamma rays and carbon ions.

In this study, we investigated the effects of glycine betaine (GB) on bone marrow death and intestinal damage by gamma rays or carbon ions. C(3)H/He female mice received an i.p.-injection of GB before or after whole-body irradiation with gamma rays or 50 keV microm(-1) carbon ions. The irradiated mice were observed to determine the mortality for 30 days after exposure. Mice were also killed at 3.5 days after the exposure to determine the intestinal damage. The numbers of crypts per transverse circumference were counted using a microscope. For the bone marrow death, GB (93 mg GB per mouse) significantly (p < 0.05) increased the percentage survival for both radiations. For the intestinal damage, GB (93 mg GB per mouse) significantly (p < 0.05) increased the crypt survival for gamma rays, but not for carbon ions. GB might be a potential protector against normal tissue damage as a side effect in radiotherapy.

Factors influencing discharge location following high lesion spinal cord injury rehabilitation in British Columbia, Canada.

STUDY DESIGN: Retrospective chart review. OBJECTIVE: To identify and describe factors that influence discharge location -- extended care unit (nursing home) or other (private home, group home, or acute care) -- following rehabilitation for individuals with a new high lesion spinal cord injury (SCI) (C1-C4) in British Columbia, Canada. SETTING: GF Strong Rehabilitation Centre, Vancouver, British Columbia, Canada. METHODS: Eligible clients were adults admitted to the GF Strong Rehabilitation Centre Spinal Cord Program between 1994 and 2003, with a new C1-4 lesion (traumatic or nontraumatic), and an ASIA score of A-C at time of discharge. Medical charts of 52 individuals were reviewed and data regarding individual characteristics, health-related characteristics, personal context, hospitalization factors, health resources, and other contextual factors were extracted. RESULTS: In total, 40% of clients were discharged to extended care units post rehabilitation. Seven variables were associated at a univariate level: age, employment at the time of injury, pre-existing medical conditions, social support, preinjury living situation, and insurance (worker's compensation or motor vehicle) or private funding for equipment. Four variables were associated at the multivariate level: age, preinjury living situation, and insurance or private funding for equipment. CONCLUSION: A range of individual, health-related, family and social policy variables influence discharge location following rehabilitation for high lesion SCI in British Columbia. The unique combination of variables presented by each individual should be considered by the rehabilitation team in the discharge planning process.

Analyses of serum lipoprotein(a) and the relation to phenotypes and genotypes of apolipoprotein(a) in type 2 diabetic patients with retinopathy.

To elucidate the association of lipoprotein(a) (Lp(a)) with diabetic retinopathy (DR), we studied the serum Lp(a) concentrations (n = 412), apolipoprotein(a) (apo(a)) phenotypes expressed by the number of kringle 4 (K4) repeats (n = 150), apo(a) gene genotypes (n = 161) of type 2 diabetes with or without DR. The 5'-untranslated region of apo(a) gene was classified into seven haplotypes (A to G) and 18 genotypes by PCR-RFLP at three distinct sites. The serum Lp(a) concentrations were significantly higher in diabetic patients than in normal controls. Furthermore, the patients with DR, especially proliferative retinopathy showed higher serum Lp(a) concentrations than those without DR. Although a negative correlation was found between the serum Lp(a) concentrations and the number of K4 repeats in total diabetic patients, no difference was seen in the distribution of the number of K4 repeats between those with and without DR. In the same apo(a) phenotypes, the patients with DR had higher Lp(a) concentrations than those without DR. Among the genotypes, type CC showed significantly higher serum Lp(a) concentrations than the other genotypes. However, there was no difference in the ratios of the type CC between the patients with and without DR. In conclusion, other factors than phenotypes and genotypes in the 5'-untranslated region of apo(a) may be responsible for the elevation of serum Lp(a) in diabetic patients with retinopathy.

Mitochondrial gene mutations in the tRNA(Leu(UUR)) region and diabetes: prevalence and clinical phenotypes in Japan.

BACKGROUND: Mitochondrial gene mutations play a role in the development of diabetes mellitus. We have assessed the frequency of the A3243G and other mitochondrial mutations in Japan and in the relationship to clinical features of diabetes. METHODS: DNA was obtained from peripheral leukocytes of 240 patients with diabetes mellitus (39 with type 1; 188 with type 2; 13 with gestational diabetes) and 125 control subjects. We used PCR-restriction fragment length polymorphism analysis (ApaI) for A3243G and PCR-single-strand conformation polymorphism analysis to determine the mutations in the mitochondrial gene including nucleotide position 3243. RESULTS: The A3243G mutation was found in seven patients, and an inverse relationship was observed between the degree of heteroplasmy and the age at onset of diabetes. A3156G, G3357A, C3375A, and T3394C were detected in addition. Those who shared the same mutation showed similar clinical characteristics, thus representing a putative clinical subtype. The patients with A3156G had a sudden onset of hyperglycemia and showed a rapid progression to an insulin-dependent state with positive anti-glutamic acid decarboxylase antibody. Those with T3394C showed a mild defect in glucose-stimulated insulin secretion, and hyperglycemia appeared after adding such factors as aging or obesity. CONCLUSIONS: The identification of mitochondrial gene mutations allows preclinical diagnosis of diabetes and prediction of the age at onset by evaluating the degree of heteroplasmy in cases with A3243G. Mutation detection may also be important for patient management and identification of affected family members.

[Intermittent administration of 5-FU and isovorin to patients with advanced and recurrent colon cancer].

We attempted a new regimen of intermittent administration of 5-FU and low-dose Isovorin (F.I) to four patients with advanced and recurrent colon cancer. A partial response (PR) was achieved in two of four patients who had evaluable lesions for this treatment. We observed few side effects among these patients. Only one patient among four showed grade 1 neuropathy after two administrations of this chemotherapy. However, after a two-week pause in administration, the neuropathy disappeared and we could continue the therapy. This patient with multiple liver metastases achieved a partial response. Other patients had no side effects such as bone marrow suppression or digestive symptoms. This intermittent F.I treatment might be an effective and promising therapy with few side effects even for patients with poorer conditions.

[Clinical experience of intermittent administration of 5-FU and CDDP to patients with advanced and recurrent gastric cancer].

We administered 5-FU and CDDP (FP) intermittently to four patients with advanced and recurrent gastric cancer. A minor response (MR) and partial response (PR) were achieved in two of four patients who had evaluable lesions for this treatment, and few side effects were observed. Only one patient among six showed grade 2 leucocytopenia after 15 administrations of this chemotherapy, when she had attained a partial response in a lung metastasis. The other patients had no side effects such as bone marrow suppression or digestive symptoms. This intermittent FP treatment may be an effective and promising therapy with few side effects even for the patients with serious conditions.

Quantitative comparison of two types of planar lipid bilayers--folded and painted--with respect to fusion with vesicles.

Two major types of planar lipid bilayers, painted and folded, were compared with respect to vesicle fusion using one chamber for the preparation of both bilayers. Liposomes containing ion channels composed of nystatin and ergosterol were used as the vesicle sample. Fusion of the liposome to either bilayer elicited a spike-like current change, which corresponds to a fusion event. The lag time between the first fusion event and the addition of the vesicles is an index of the ease with which the vesicles fuse with the bilayers. The lag time in the painted bilayer at a KCl concentration (cis) of 450 mM was 1.58+/-1.18 min, similar to that in the folded bilayer (1.65+/-0.64 min). The lag time decreased with increase of the osmotic difference across the painted bilayer, whereas this change was small in the folded bilayer. The fusion of the liposomes to the painted bilayer was markedly reduced by stopping the stirring in the cis compartment, whereas the fusion to the folded bilayer was not affected significantly. These results imply that no practical difference exists in the ability of vesicles to fuse with the painted and folded bilayers. For the study of single channel behavior, the painted bilayer could have an advantage because simply stopping the stirring prevents excess fusion.

Solution structure of micelle-bound H5 peptide (427-452): a primary structure corresponding to the pore forming region of the voltage dependent potassium channel.

A 26-mer peptide with the sequence of the pore forming region (residues 427-452) of the Shaker K(+) channel (H5 region) was chemically synthesized. Analyses by CD and two-dimensional 1H NMR spectroscopy were used to investigate the structure of the peptide bound to SDS micelles in solution, which are commonly used in biophysical studies. The tertiary structure of the peptide as a monomer was composed of an alpha-helix (431-438), a turn (439-442), and random coils (427-430, 443-452), and was very similar to that of the pore forming region of the native K(+) channel from Streptomyces lividans determined by X-ray analysis. This result suggests that even an isolated peptide forms a native-like conformation for residues from 431 to 442, depending on its intrinsic amino acid sequence and the surrounding environment.

Pathophysiological significance of in vivo ESR signal decay in brain damage caused by X-irradiation. Radiation effect on nitroxyl decay of a lipophilic spin probe in the head region.

X-irradiation of mice decreased the decay rate of the in vivo ESR signal in the head region to 75% of the control when 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy (MCPROXYL), a lipophilic and blood-brain barrier-permeable spin probe, was used. We attempted to identify the specific factor responsible for the decrease in the signal decay rate caused by X-irradiation. The signal decay of MCPROXYL in the head region depends on the following three factors: (1) blood concentration of MCPROXYL, (2) reduction to the corresponding hydroxylamine in the brain tissue, and (3) effusion of MCPROXYL from the brain tissue. Irradiation at 15 Gy did not significantly change the rate of decrease of blood concentration of MCPROXYL at 1 h post-irradiation. The reducing activity of the brain homogenate was not changed by the X-irradiation (15 Gy). The contents of MCPROXYL and its hydroxylamine derivative in the brain of 15 Gy-irradiated mice remained higher than in non-irradiated mice. These findings suggest that the effect of X-irradiation observed by in vivo ESR is attributable not to the redox reaction of MCPROXYL in the brain but to the change of the efflux rate of the MCPROXYL from the brain.

Elevated serum-soluble Fas ligand in histiocytic necrotizing lymphadenitis.

Recent studies have indicated that Fas and perforin-based mechanisms seem to induce apoptosis in histiocytic necrotizing lymphadenitis (HNL). In this study, we evaluated the serum levels of soluble Fas ligand (sFasL) in 30 HNL patients using paired sera. Elevations in sFasL levels were detected in 9 patients in the active stage. In the convalescent stage, the levels of sFasL decreased to an undetectable degree after 2 weeks. These findings indicate the possibility that sFasL plays an important role in the constitutional symptoms and pathogenesis of HNL and, furthermore, that it can act as a surrogate marker of the disease activity.

Pur alpha protein implicated in dendritic RNA transport interacts with ribosomes in neuronal cytoplasm.

We have previously reported that pur alpha, known to be a regulator of DNA replication and transcription, links neural BC1 RNA to microtubules via dendrite-targeting RNA motifs. Here we demonstrate the subcellular localization of pur proteins within the brain. Pur proteins were detected in neurons but not in glia. Immunohistochemical staining was prominent in perikarya and proximal dendrites and also extended into primary dendritic processes, but no significant signals were detected in the distal regions of dendrite. When homogenates of mouse brain were fractionated, pur alpha was most concentrated in the microsomal pellet. Consistently, pur alpha co-fractionated with free polysomes as well as with membrane-bound polysomes and the association with polysomes was mediated by binding ribosomal subunits. Levels of ribosomes with pur alpha progressively increased during postnatal development of the brain.

Neural BC1 RNA associates with pur alpha, a single-stranded DNA and RNA binding protein, which is involved in the transcription of the BC1 RNA gene.

BC1 RNA is preferentially expressed in neural cells by RNA polymerase III (Pol III) and forms ribonucleoprotein particles (RNP) in the somatodendritic domain of neurons. Our previous studies have suggested that, in the nucleus, BC1 RNA forms an RNP containing a nuclear protein(s) that participates in the transcription of the BC1 RNA gene. In this study, we have shown that newly synthesized BC1 RNA in purified brain nuclear extracts is immunoprecipitated by an antibody against Pur alpha. Pur alpha is a protein that binds single-stranded DNA and RNA and is known to regulate transcription of Pol II system. Although BC1 RNA is transcribed by Pol III, the BC1 RNA gene has two putative Pur alpha binding sites, which Pur alpha specifically recognizes. Point mutations within these sites reduced transcriptional activity in vitro. Furthermore, transcription was inhibited by depletion of Pur alpha from the nuclear extracts, either by the coexistence of its binding region of BC1 RNA or by the antibody that was able to precipitate the nuclear BC1 RNP. These observations suggest that BC1 RNA associates with Pur alpha which is involved in the transcription of the BC1 RNA gene.

Novel approach to in vivo screening for radioprotective activity in whole mice: in vivo electron spin resonance study probing the redox reaction of nitroxyl.

Previously, we reported that X-irradiation enhanced the signal decay of a spin probe injected into whole mice measured by in vivo ESR, and that the observed enhancement was suppressed by the pre-administration of cysteamine, a radioprotector [Miura, Y., Anzai, K., Urano, S. and Ozawa, T. (1997) Free Rad. Biol. Med. 23: 533-540]. In the present study, the suppression activity of the X-ray-induced increase in the ESR signal decay rate (termed suppression index, SI) was measured for several radioprotectors: 5-hydroxytryptamine (5-HT), S-2-(3-aminopropylamino)-ethylphosphorothioic acid (WR-2721), 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl (TEMPOL), cimetidine, interleukin-1 beta (IL-1 beta) and stem cell factor (SCF). The enhancement of the ESR signal decay of carbamoyl-PROXYL due to X-irradiation was suppressed by a treatment with all of the radioprotectors examined, showing positive SI values. However, a dose-dependency of 5-HT or WR-2721 was not observed, suggesting that several mechanisms exist for radioprotection and a modification of the signal decay rate. Although the in vivo ESR system cannot be used in place of the 30-day survival method for the assessment of radioprotectors, this system might be applicable to in vivo, non-invasive screening prior to using the 30-day survival method.

The single-stranded DNA- and RNA-binding proteins pur alpha and pur beta link BC1 RNA to microtubules through binding to the dendrite-targeting RNA motifs.

Neural BC1 RNA is distributed in neuronal dendrites as RNA-protein complexes (BC1 RNPs) containing Translin. In this study, we demonstrated that the single-stranded DNA- and RNA-binding protein pur alpha and its isoform, pur beta, which have been implicated in control of DNA replication and transcription, linked BC1 RNA to microtubules (MTs). The binding site was within the 5' proximal region of BC1 RNA containing putative dendrite-targeting RNA motifs rich in G and U residues, suggesting that in the cytoplasm of neurons, these nuclear factors are involved in the BC1 RNA transport along dendritic MTs. The pur proteins were not components of BC1 RNP but appeared to associate with MTs in brain cells. Therefore, it is suggested that they may transiently interact with the RNP during transport. In this respect, the interaction of pur proteins with BC1 RNA could be regulated by the Translin present within the RNP, because the binding mode of these two classes of proteins (pur proteins and Translin) to the dendrite-targeting RNA motifs was mutually exclusive. As the motifs are well conserved in microtubule-associated protein 2a/b mRNA as well, the pur proteins may also play a role(s) in the dendritic transport of a subset of mRNAs.