[Determination of rare-earth impurities in ultra-highly pure Er2O3 and Ho2O3 by [HEH(HEP)] extraction chromatography-atomic emission spectrometry]

This article applied [HEH(HEP)] (2-ethyhexyldrogen-2-ethylhexyl phosphonate) extraction chromatography to separate 14 rare earth impurities from ultra-highly pure Er2O3 and Ho2O3, and then the impurities were determined by atomic emission spectrometry. The average percentage recovery for each element is in the range of 70%-140%. The relative standard deviations of the determination are +/- 3.3%-2.2%. This method can be applied to the determination of the trace amounts of rare eath impurities in Er2O3 and Ho2O3 with a purity of 99.9999%-99.99999%.

Feedback regulation of thyrotropin-releasing hormone gene expression by thyroid hormone in the caudal raphe nuclei in rats

Medullary TRH regulates autonomic activity, and altered thyroid status is associated with autonomic disorders. We investigated whether thyroid hormone exerts a negative feedback regulation on TRH gene expression in the medullary caudal raphe nuclei. Medullary pro-TRH messenger RNAs (mRNAs) were mainly located in the raphe pallidus and raphe obscurus neurons as shown by in situ hybridization and were significantly increased by 70% and 160-230% by Northern blot analyses in 24 h fasted rats at 1 and 3-5 weeks after thyroidectomy, respectively, when serum T4 levels were reduced by 75-87%. The increased pro-TRH mRNA on the 30th day after thyroidectomy was reversed to euthyroid levels by T4 replacement (2 or 4 microg/100 g x day). T4 injections (10 or 100 microg/100 g x day for 30 days) did not significantly influence medullary pro-TRH mRNA levels in sham-operated rats. Thyroidectomized rats fed normally showed a 500% increase in pro-TRH mRNA levels 30 days after the surgery, while those fasted for 24 h showed only a 180% increase. These data indicate that medullary TRH gene expression is enhanced during hypothyroidism due to the lack of negative feedback regulation by thyroid hormone, and this response is modulated by feeding state. These findings may have important relevance to understanding autonomic-related visceral alterations induced by hypothyroidism.

[Discovery of ten strains of non-O1 Vibrio cholerae pigmentogens]

OBJECTIVE

To study the distribution of non-O1 Vibrio cholerae pigmentogens in water and its biological characteristics and pathogenicity.

METHODS

Samples were collected from local source of drinking water and cultured for pathogenic V. cholerae. Non-O1 V. cholerae was isolated and identified with nutrient agar slant instead of KIA.

RESULTS

Ten strains of V. cholerae producing pigment with negative Gram's stain were detected in the source water in Lu' an Prefecture, Anhui Province during 1994 to 1997, which could all met the definition of non-O1 V. cholerae in morphology, cultural characteristics, biochemistry and serology, with systematic identification. Animal experiments showed that it had strong virulence.

CONCLUSION

These strains of V. cholerae cultured in basic cholate agar, nutrient agar slant and blood agar could produce brown pigment, so it was called non-O1 V. cholerae pigmentogens.

[Determination of copper, iron and zinc in hair of mentally retarded children by oscillopolarography]

The oscillopolarographic method (proposed by Ding Jianwen)for the simulltaneous determination of copper, iron and zinc in hair was further studied and applied to the investigation of copper, iron, zinc content in hair samples from 46 mentally retarded children and 49 healthy children. For copper, iron, zinc, the detection limits were 0.03, 0.03, 0.01 microgram/ml, dynamic range 0.05-15, 0.05-2.5, 0.2-10 micrograms/ml, the RSD of sample analysis 3.2%, 3.3%, 2.4%, the recoveries 96: 0%-105.2%, 2%, 97.3%-109.0%, 94.7%-107.7%, respectively. The difference between the results for the same sample by this method and the atomic absorption spectroscopic method was no statistical significance. The results showed that the copper content and iron content of hair samples from mentally retarded children were significantly lower than those of healthy children.

Increase in AP-1 transcription factor DNA binding activity by valproic acid

Valproic acid (VPA), a simple branched fatty acid anticonvulsant, has been demonstrated to have clinical efficacy in the treatment of manic-depressive illness (Bowden et al., 1994), but the mechanism(s) by which VPA produces its therapeutic effects remain to be elucidated. VPA's clinical antimanic action require a lag period for onset and are not immediately reversed upon discontinuation of treatment, effects that suggest alterations at the genomic level; we therefore investigated the effects of VPA on the modulation of the DNA binding activity of key transcription factors. DNA binding activities of activator protein 1 (AP-1) and cAMP responsive element binding protein (CREB) were studied in acute (hours) and chronic (days) VPA-treated rat C6 glioma cells. VPA did not affect CREB DNA binding activity, but concentration- and time-dependently increased AP-1 DNA binding activity. The activity was raised at 2 hours (the shortest time examined) and remained high after 6 days (the longest time used) of continuing VPA treatment. VPA also enhanced AP-1 DNA binding activity in human neuroblastoma (SH-SY5Y) cells. Because the effects of VPA were markedly inhibited by cycloheximide, they appear to require new protein synthesis. Taken together, the data suggest that antimanic agents may affect gene expression by modulation of the activity of major transcription factors; in view of the key roles of these nuclear transcription regulatory factors in long-term neuronal plasticity and cellular responsiveness, these effects may play a major role in VPA's therapeutic efficacy and are worthy of further study.

Main chain and side chain dynamics of peptides in liquid solution from 13C NMR: melittin as a model peptide

Peptide backbone and lysine and tryptophan side chain mobilities in the synthetic, 26-residue peptide melittin (MLT) enriched with 13C were investigated in liquid solution by 13C T1 and steady state nuclear Overhauser effect measurements at two magnetic fields and by Trp fluorescence anisotropy measurements and were analyzed using the Lipari and Szabo model-free approach. The overall rotational correlation times at 20 degrees C were 1.28, 1.4, 2.8, and 4.2 ns for monomeric random coil MLT, for monomeric helical MLT (in CD3OD), for tetrameric MLT in neat D2O, and for the tetramer in 50 mM phosphate buffer, respectively. Motion of the backbone in the interior of the sequence was most restricted in the monomeric helix and least restricted in the tetramer. In the monomeric disordered peptide, relatively less restricted backbone motion extending from the N terminus to the fourth residue was observed. Such "end effects" continued only to the third residue in the monomeric helix and were observed just in the amino terminus glycine in the tetramer. The three Lys side chains showed the least restricted motion in the monomers and a differential restriction in the tetramers consistent with the tetramer structure. The motion of the Trp side chain was more restricted than that of Lys side chains and generally as restricted as that of the interior backbone atoms. The effective correlation times for the local motion of the backbone atoms were in the motional narrowing limit and showed distinct patterns. Agreement between NMR relaxation and Trp fluorescence anisotropy data was good for the monomer but not for the tetramer. Implications of these results for peptide dynamics in general are examined.

Distinct functional domains in the cowpea mosaic virus movement protein

Cell-to-cell movement of cowpea mosaic virus particles in plants takes place with the help of tubules that penetrate presumably modified plasmodesmata. These tubules, which are built up by the virus-encoded 48-kDa movement protein (MP), are also formed on single protoplast cells. To determine whether the MP contains different functional domains, the effect of mutations in its coding region was studied. Mutations between amino acids 1 and 313 led to complete abolishment of the tubule-forming capacity, while a deletion in the C-terminal region resulted in tubules that could not take up virus particles. From these observations, it is concluded that the MP contains at least two distinct domains, one that is involved in tubule formation and that spans amino acids 1 and 313 and a second that is probably involved in the incorporation of virus particles in the tubule and that is located in the C terminus between amino acids 314 and 331.

Structure and dynamics of melittin in lysomyristoyl phosphatidylcholine micelles determined by nuclear magnetic resonance

Mixed micelles of the 26-residue, lytic peptide melittin (MLT) and 1-myristoyl-2-hydroxyl-sn-glycero-3-phosphocholine (MMPC) in aqueous solution at 25 degrees C were investigated by (13)C- and (31)P-NMR spectroscopy. (13)C alpha chemical shifts of isotopically labeled synthetic MLT revealed that MLT in the micelle is predominantly alpha-helical and that the peptide secondary structure is stable from pH 4 to pH 11. Although the helical transformation of MLT as determined from NMR is evident at lipid:peptide molar ratios as low as 1:2, tryptophan fluorescence measurements demonstrate that well-defined micellar complexes do not predominate until lipid:peptide ratios exceed 30:1. (31)P linewidth measurements indicate that the interaction between phosphate ions in solution and cationic groups on MLT is pH dependent, and that the phosphoryl group of MMPC senses a constant charge, most likely +2, on MLT from pH 4 to pH 10. (13)C-NMR relaxation data, analyzed using the model-free formalism, show that the peptide backbone of MLT is partially, but not completely, immobilized in the mixed micelles. Specifically, order parameters (S(2)) of C alpha-H vectors averaged 0.7 and were somewhat larger for residues in the N-terminal half of the molecule. The amino terminal glycine had essentially the same range of motion as the backbone carbons. Likewise, order parameters for the trp side chain were similar to those found for the peptide C alpha moieties, as was verified by trp fluorescence anisotropy decay data. In contrast, the motion of the lysine side chains was less restricted, the average S(2) values for the C epsilon-H vectors being 0.19, 0.30, and 0.44 for lys-7, 21, and 23, respectively, for MLT in the mixed micelles. Values of the effective correlation time of the local motion tau e were in the motional narrowing limit and usually longer for side-chain atoms than for those in the backbone. The dynamics were independent of pH from pH 4 to pH 9, but at pH 11 the correlation time for the rotational motion of the mixed micelles as a whole increased from 10 ns to 16 ns, and S(2) for the lys side chains increased. Overall it appears that the MLT helix lies near the surface of the micelle at low to neutral pH, but at higher pH its orientation changes, accompanied by deeper penetration of the lysine side chains into the micelle interior. It is apparent, however, that the MLT-lipid interaction is not dependent on deprotonation of any of the titratable cationic groups in the peptide in the pH 4-10 range, and that there is substantial backbone and side-chain mobility in micelle-bound MLT.

[Alteration of drinking pattern after the entrance of university]

Three hundred fifty-nine freshmen and freshwomen of Tokai University and Tamagawa University were examined for alcohol habituelle using questionnaires on life style and club activity as well as the established questionnaires of the Adolescent Alcohol Involvement scale (AAIS). The scores of AAIS of the male and female students were 30.6 and 27.7, respectively. About 10% of the subjects were revealed to be alcohol misusers. In both sexes, the drinking patterns remarkably changed after the entrance of university. Even in females, the drinking pattern markedly changed. The grade of club activity is one of factors influencing the drinking pattern of students. Especially big changes were observed in the students of cultural clubs.

Anal atresia: effect of smoking and drinking habits during pregnancy

Using data compiled from 216,707 births from the population-based Kanagawa Birth Defects Monitoring Program (KAMP), we conducted a case-control study to evaluate the effect of maternal smoking and/or drinking during pregnancy on the risk of infants' anal atresia in 1989-1994. The frequency of maternal smoking (including passive smoking) and/or maternal drinking during pregnancy among 84 infants with anal atresia was compared with 174 matched controls. The 84 anal atresias include 49 cases of isolated anal atresia and 35 cases of syndromal anal atresia. Our findings suggest that maternal drinking during early pregnancy is associated with an increased risk of isolated anal atresia (OR = 4.8, 95% CI 1.2 to 19.1, p < 0.05). A slightly increased trend was also observed in the association of maternal smoking during pregnancy with both in the pooled groups of anal atresia (OR = 1.4, 95% CI 0.5 to 3.6).

N-terminus and lysine side chain pKa values of melittin in aqueous solutions and micellar dispersions measured by 15N NMR

Melittin (MLT) is a 26-amino acid cytolytic peptide from the Apis mellifera honey bee. It is known to exist as an alpha-helical tetramer, as an alpha-helical monomer, or as a monomeric random coil depending on solvent conditions. The charge state of MLT is believed to be a major factor in determining its aggregation properties and its interaction with lipids. Several, contradictory, indirect measurements of the pKa values of the three lysine groups in MLT have been reported. In the present study, high-resolution 15N NMR at 50.6 MHz was used to directly measure the pKa values of the amino groups of the Gly-1, Lys-7, Lys-21, and Lys-23 residues of MLT. Specifically, the pH dependence of MLT 15N chemical shifts was measured separately for the isotopically enriched backbone nitrogen of Gly-1 and the side chain nitrogen atoms of Lys-7, Lys-21, and Lys-23 at a MLT concentration of 1.2 mM and a temperature of 23 degrees C. Measurements were made for MLT in potassium phosphate buffer, in neat water, and in 1-myristoyl-2-hydroxyl-sn-glycero-3-phosphocholine (MMPC) lipid micelles. The experiments showed for MLT tetramer in aqueous phosphate buffer that the amino nitrogen of Gly-1 has a pKa of 8.15, and that the Lys-7, Lys-21, and Lys-23 side chain nitrogen atoms have pKa values of 10.21, 10.03, and 10.24 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

[Quantitative determination of ursolic acid in folium Ilicis cornutae (gouguye) gathered in different and periods]

The content of ursolic acid in Folium Ilicis Cornutae (Gouguye) gathered in different periods from Yongfeng county of Jiangxi province was determined by TLCS method. The result shows that the content appears to be low in samples gathered in April, but about the same in samples of February, June, August, October and December.

Clinical trials of immunoadsorbent in systemic lupus erythematosus therapy

Five patients with systemic lupus erythematosus (SLE) were perfused through an extracorporeal shunt filled with DNA-immunoadsorbent (DNA immobilized on carbonized resin beads). High concentrations of anti-DNA antibodies (36.4-67.0%) (binding percentage with 125I-DNA) in the serum of SLE patients were reduced to 13.8-53.0%, respectively. The highest removal percentage was 62.1%. Although the decline levels varied, the symptoms of patients, i.e., long-term severe joint pain, severe edema, hydropericardium, and ascites were all relieved considerably. The immunoadsorbent showed satisfactory blood compatibility.

Increasing neuroforaminal volume by anterior interbody distraction in degenerative lumbar spine

STUDY DESIGN

This study quantified changes in the size of the stenotic neuroforamen in degenerative lumbar spines. The volume and area of the neuroforamen were measured before and after the application of anterior distraction using the BAK interbody fusion system.

OBJECTIVE

To quantitatively assess the neuroforaminal area and volume when the BAK interbody fusion system is applied to lumbar spines with neuroforaminal stenosis.

SUMMARY OF BACKGROUND DATA

The spatial relationship between the nerve root and the osseous and nonosseous elements of the neuroforamen is clinically important. Few studies have focused on changes in neuroforaminal size in the lumbar spine after anterior interbody distraction. No previous study has assessed the neuroforaminal volume.

METHODS

The BAK instrumentation system was applied anteriorly at L4-L5 and L5-S1 intervertebral discs in nine degenerative cadaver lumbar spines. The neuroforaminal volumes of L4-L5 and L5-S1 were measured from silicon molds taken of the neuroforamen. In addition, computed tomography and circular blunt probes were used to determine the neuroforaminal areas. The disc height was recorded from lateral radiographs.

RESULTS

After the BAK instrumentation, the volume of the neuroforamen increased significantly--by 22.9% for L4-L5 and 21.5% for L5-S1. The posterior disc height increased by 37.1% at L4-L5 and 45.1% at L5-S1. The neuroforaminal areas significantly increased--by 29.0% at L4-L5 and 33.8% at L5-S1. There was good correlation between the volume and the posterior disc height (R2 = 0.50) and the volume and the area of the narrowest portion of neuroforamen (R2 = 0.56).

CONCLUSIONS

The results indicated that anterior systems such as the BAK system, which increase disc heights, can significantly increase neuroforaminal volume and area, providing adequate space for the nerve root and improving neuroforaminal stenosis.

[Effects of aging on urinary secretion of 3-hydroxyproline and its importance for cancer screening in the elderly with ROC analysis]

OBJECTIVE

to observe the influence of aging on urinary secretion of 3-hydroxyproline (3-Hyp) in normal subjects and in cancer patients and study the effects of aging on the accuracy of urinary 3-Hyp as a general-purpose cancer screening test.

DESIGN

We reanalyzed, from the aspect of gerontology, the amounts of 3-Hyp in the urine samples of the 211 healthy persons and 94 patients with cancer reported earlier. The two groups were divided in 3 age subgroups: adult, 30 to 44 years, middle-aged, 45 to 64 years, and aged, 65 years and older. The cancer stage was separated into 3 categories: stage 1, the early stage without any invasion, stage 2, locally invasive with no distant metastasis, and stage 3, advanced cancer. The correlation of age and urinary 3-Hyp was analyzed in normal subjects and cancer patients. Sensitivity and specificity were calculated for different cutoff points in the diverse groups to construct the receiver operating characteristic (ROC) curves.

MAIN RESULTS

We observed that aging decreases the urinary secretion of 3-Hyp in normal subjects, with a correlation coefficient of -0.250 (p < 0.001). The mean levels of urinary 3-Hyp in patients with cancer were significantly higher than in the normal subjects, p = 0.005. The correlation coefficient of urinary 3-Hyp and age was not significant (0.100) in cancer patients. The cutoff points of 0.800 mg/g creatinine of urinary 3-Hyp for persons under 65 years of age and 0.600 mg/g creatinine for persons 65 years or older were the best thresholds for cancer screening. In the ROC analyses, we observed that 3-Hyp has higher accuracy for cancer screening in the aged group for all stages together and in the aged and middle-aged for early stages of cancer.

CONCLUSIONS

The urinary 3-Hyp test was more effective for cancer screening in old persons (65 years or older), where cancer is more frequent and more difficult to discover. The authors stress the necessity and importance of verifying the effectiveness of urinary 3-Hyp for general cancer screening in a larger population and in a community set.

[Maternal drinking and smoking and the risk of birth defects]

Maternal drinking or smoking and the risk of birth defects was studied in a case-control study, performed on 1,789 babies, born between 1990 and 1992 in the Tokai University hospital, and their mothers. The findings were as follows: The proportion of maternal drinking before or during pregnancy was higher in the mothers of children with birth defects (odds ratio 2.2; 95% confidence intervals 0.5-8.9). However, this difference was not statistically significant. Maternal smoking, defined as 11 or more cigarettes per day before pregnancy, was 13.5% in the mothers of children with birth defects, compared to 6.7% in the mothers of controls (odds ratio 2.2; 95% CI 0.6-7.4). This difference was not statistically significant. A total of 78 classified deformities were reported in the 52 children with birth defects, of which 24.4% were associated with maternal drinking and 16.7% were associated with maternal smoking, respectively. A significant association was found between premature birth and mothers who reported drinking during pregnancy (odds ratio 3.3 95% CI 1.1-10.9). The frequency of spontaneous abortion was higher among mothers who reported both drinking and smoking during pregnancy. In addition the frequency of complications during pregnancy was higher. Analysis of factors related to birth defects showed that the risk for birth defective infants was higher for mothers above 35 years of age than for those under 35 (p < 0.05). This study supports an association between maternal drinking during pregnancy and infant birth defects, but does not implicate maternal smoking because the number of mothers who smoked during pregnancy was too small to be of significance.

13C NMR and fluorescence analysis of tryptophan dynamics in wild-type and two single-Trp variants of Escherichia coli thioredoxin

The rotational motion of tryptophan side chains in oxidized and reduced wild-type (WT) Escherichia coli thioredoxin and in two single-tryptophan variants of E. coli thioredoxin was studied in solution in the temperature range 20-50 degrees C from 13C-NMR relaxation rate measurements at 75.4 and 125.7 MHz and at 20 degrees C from steady-state and time-resolved trp fluorescence anisotropy measurements. Tryptophan enriched with 13C at the delta 1 and epsilon 3 sites of the indole ring was incorporated into WT thioredoxin and into two single-trp mutants, W31F and W28F, in which trp-28 or trp-31 of WT thioredoxin was replaced, respectively, with phenylalanine. The NMR relaxation data were interpreted using the Lipari and Szabo "model-free" approach (G. Lipari and A. Szabo. 1982. J. Amer. Chem. Soc. 104:4546-4559) with trp steady-state anisotropy data included for the variants at 20 degrees C. Values for the correlation time for the overall rotational motion (tau m) from NMR of oxidized and reduced WT thioredoxin at 35 degrees C agree well with those given by Stone et al. (Stone, M. J., K. Chandrasekhar, A. Holmgren, P. E. Wright, and H. J. Dyson. 1993. Biochemistry. 32:426-435) from 15N NMR relaxation rates, and the dependence of tau m on viscosity and temperature was in accord with the Stokes-Einstein relationship. Order parameters (S2) near 1 were obtained for the trp side chains in the WT proteins even at 50 degrees C. A slight increase in the amplitude of motion (decrease in S2) of trp-31, which is near the protein surface, but not of trp-28, which is partially buried in the protein matrix, was observed in reduced relative to oxidized WT thioredoxin. For trp-28 in W31F, order parameters near 1 (S2 > or = 0.8) at 20 degrees C were found, whereas trp-31 in W28F yielded the smallest order parameters (S2 approximately 0.6) of any of the cases. Analysis of time-resolved anisotropy decays in W28F and W31F yielded S2 values in good agreement with NMR, but gave tau m values about 60% smaller. Generally, values of tau e, the effective correlation time for the internal motion, were < or = 60 ps from NMR, whereas somewhat longer times were obtained from fluorescence. The ability of NMR and fluorescence techniques to detect subnanosecond motions in proteins reliably is examined.

An approach to sequence-specific antibody proteases. The use of haptens mimicking both a transition state and a distorted ground state

We describe here a novel strategy for the isolation of antibodies with sequence-specific protease activity: the synthesis of dipeptide haptens in which the targeted peptide bond has been replaced by a ring-strained or torsionally strained hydroxyethylene transition-state analog. Thus, the analogs mimic both a peptide bond in a distorted, reactive conformation and the transition state for peptide bond hydrolysis. In order to obtain sequence-specific antibody proteases, these analogs have been flanked with additional amino acid residues in preparation for immunization. In particular, we have synthesized peptides containing analogs such as 2-cis-amino-3-cis-hydroxycyclobutane carboxylic acid and endo-(3-amino-2-hydroxy)bicyclo[2.2.1]-heptane-7-anti-carboxylic acid. We have also prepared a series of peptide derivatives containing analogs, such as 2-[3-amino-2-oxo-1-azetidinyl]-3-methylbutanoic acid, in which the targeted peptide bond has been incorporated into a beta-lactam ring. Since the "peptide bond" has been left intact, these species mimic only a distorted ground state. At present, antibodies are being elicited against a number of the above peptide derivatives.

Clinical trials for removal of bilirubin by high-capacity nonionic adsorbent

To remove bilirubin from patients with hyperbilirubinemia, nonionic macroporous adsorbent NK-110 was tailor-made from styrene and divinyl benzene at Nankai University. Five patients were perfused through shunts filled with 500 ml of the above adsorbent. After 2 h of hemoperfusion, total bilirubin decreased within the range of 22-51%. During the treatment, no noticeable changes in electrolytes, urea nitrogen, serum glutamicpyruvic transaminase (SGPT), TTT, and amino acid concentrations were observed. Platelet depletion was satisfactory. Hemoglobin, white cell count, globulin, and albumin showed no remarkable changes. The nonionic adsorbent shows a high efficacy for bilirubin removal and has a great potential for future clinical applications.

[Analysis of chemical constituent of essential oil in Lonicera japonnica Thunb. cultivated on the northern plain of Henan Province]

The chemical constituents of the essential oil in the dry flower and fresh flower of Lonicera japonica were analyzed by the GC-MS-DS technique and the superimposition of authentic samples. 27 and 30 monoterpenoids and sesquiterpenoids were identified from the essential oil of the dry flower and fresh flower respectively. The major constituents have been found to be linalool, geraniol, aromadendrene and eugenol etc.