Biomedical subjects

J Zhao

Publications and source records attributed to J Zhao.

At least 235 records · Page 13Linked to original sources

PubMed2000

Molecular cloning and sequencing of the sodB gene from a heterocystous cyanobacterium Anabaena sp. PCC 7120.

Superoxide dismutase (Sod) plays an important role in all aerobic organisms. The sodB gene of a heterocystous cyanobacterium Anabaena sp. PCC 7120 was cloned and sequenced. The Sod protein is predicted to have 199 amino acids and a molecular mass of 22.5 kDa. Sequence comparison among SodB from cyanobacteria and chloroplasts revealed that the sodB gene indeed encodes an iron-Sod. Northern blot analysis showed that the sodB gene of Anabaena sp. PCC 7120 is transcribed as a single gene and its expression was up-regulated when the cells were subjected to a shift from a nitrogen repletion condition to a nitrogen depletion condition.

Amino Acid Sequence↗

PubMed2000

Transcriptional control of the human plasma membrane phospholipid scramblase 1 gene is mediated by interferon-alpha.

Interferons (IFNs) mediate their diverse biologic activities through induction of the expression of multiple genes. Whereas the mode of action of certain of these IFN-regulated genes has been well characterized, most of the molecular and cellular events underlying the constellation of biologic responses to the IFNs remain unresolved. This study showed that the newly identified PLSCR1 gene for phospholipid scramblase, previously implicated in remodeling of plasma membrane phospholipids, is regulated at the transcriptional level by IFN-alpha. Analysis of 5' flanking genomic sequence in reporter constructs showed that transcriptional control of PLSCR1 was entirely regulated by a single IFN-stimulated response element located in the first exon. A similar induction of PLSCR1 by IFN-alpha2a was also observed in a variety of other human tumor cell lines as well as in human umbilical vein endothelial cells. In these cell lines, the marked IFN-alpha2a-induced increase in PLSCR1 protein expression, ranging as high as 10-fold above basal levels, was not accompanied by increased cell surface exposure of phosphatidylserine, suggesting that remodeling of the cell surface requires both exposure to IFN and a second yet-to-be identified event to stimulate plasma membrane phospholipid scramblase activity and to mobilize phosphatidylserine to the cell surface. (Blood. 2000;95:2593-2599)

Carrier Proteins↗

PubMed2000

High-temperature ultrafast liquid chromatography.

A novel liquid chromatographic system which enables high temperature ultrafast liquid chromatography (HTU-FLC) has been designed through the careful consideration of heat transfer, band broadening, and pressure drop. Studies of the effect of linear velocity on the HETP show that column efficiency at high velocity, especially of well-retained solutes, dramatically improves at higher temperatures. At 150 degrees C, at a flow rate of 15 mL/min with a 5 cm by 4.6 mm (i.d.) column packed with 3 microns polystyrene-coated zirconia porous particles, long chain alkylphenones were completely resolved, and the analysis time could be decreased by a factor of 50 compared to that at room temperature (25 degrees C) at a conventional flow rate (4 mL/min). In addition, using pure water as the mobile phase, five phenols were separated in less than 30 s.

Chromatography, Liquid↗

PubMed2000

Posterior lumbar interbody fusion using posterolateral placement of a single cylindrical threaded cage.

STUDY DESIGN: An in vitro biomechanical study of posterior lumbar interbody fusion (PLIF) with threaded cages was performed on 18 bovine lumbar functional spinal units. OBJECTIVES: To compare the segmental stiffness among PLIF with a single long posterolateral cage, PLIF with a single long posterolateral cage and simultaneous facet joint fixation, and PLIF with two posterior cages. SUMMARY OF BACKGROUND DATA: In most cases, PLIF with threaded cage techniques needs bilateral facetectomy, extensive exposure, and retraction of the cauda equina. Posterior element deficiency is detrimental to postoperative segmental stiffness. METHODS: All specimens were tested intact and with cage insertion. Group 1 (n = 12) had a long threaded cage (15 x 36 mm) inserted posterolaterally and oriented counter anterolaterally on the left side by posterior approach with left unilateral facetectomy. Group 2 (n = 6) had two regular-length cages (15 x 24 mm) inserted posteriorly with bilateral facetectomy. Six specimens from Group 1 were then retested after unilateral facet joint screw fixation in neutral (Group 3). Similarly, the other six specimens from Group 1 were retested after fixation with a facet joint screw in an extended position (Group 4). Nondestructive tests were performed in pure compression, flexion, extension, lateral bending, and torsion. RESULTS: The PLIF procedure involving a single cage (Group 1) had a significantly higher stiffness than PLIF with two cages (Group 2) in left and right torsion (P < 0.05). Group 1 had higher stiffness values than Group 2 in pure compression, flexion, and left and right bending, but differences were not significant. Group 3 had a significant increase in stiffness in comparison with Group 1 for pure compression, extension, left bending, and right torsion (P < 0.05). For Group 4, the stiffness significantly increased in comparison with Group 1 for extension, flexion, and right torsion (P < 0.05). Although there was no significant difference between Groups 3 and 4, Group 4 had increased stiffness in extension, flexion, right bending, and torsion. CONCLUSIONS: Posterior lumbar interbody fusion with a single posterolateral long threaded cage with unilateral facetectomy enabled sufficient decompression while maintaining most of the posterior elements. In combination with a facet joint screw, adequate postoperative stability was achieved.

Animals↗

PubMed2000

beta-arrestin differentially regulates the chemokine receptor CXCR4-mediated signaling and receptor internalization, and this implicates multiple interaction sites between beta-arrestin and CXCR4.

The chemokine receptor CXCR4 has recently been shown to be a co-receptor involved in the entry of human immunodeficiency virus type 1 into target cells. This study shows that coexpression of beta-arrestin with CXCR4 in human embryonic kidney 293 cells attenuated chemokine-stimulated G protein activation and inhibition of cAMP production. Truncation of the C-terminal 34 amino acids of CXCR4 (CXCR4-T) abolished the effects of beta-arrestin on CXCR4/G protein signaling, indicating the functional interaction of the receptor C terminus with beta-arrestin. On the other hand, receptor internalization and the subsequent activation of extracellular signal-regulated kinases were significantly promoted by coexpression of beta-arrestin with CXCR4, whereas the C-terminal truncation of CXCR4 did not affect this regulation of beta-arrestin, suggesting that beta-arrestin can functionally interact with CXCR4 with or without the C terminus. Moreover, beta(2)V54D, the dominant inhibitory mutant of beta-arrestin 2, exerted no effects on CXCR4/G protein signaling, but strongly influenced receptor internalization and extracellular signal-regulated kinase activation. Further cross-linking experiments demonstrated that beta-arrestin as well as beta(2)V54D could physically contact both CXCR4 and CXCR4-T. Glutathione S-transferase pull-down assay showed that beta-arrestin was able to bind efficiently in vitro to both the third intracellular loop and the 34-amino acid C terminus of CXCR4. Taken together, our data clearly establish that beta-arrestin can effectively regulate different functions of CXCR4 and that this is mediated through its distinct interactions with the C terminus and other regions including the third loop of CXCR4.

Arrestins↗

PubMed2000

A comparative study of the chromatographic selectivity of polystyrene-coated zirconia and related reversed-phase materials.

The chromatographic selectivities of polystyrene-coated zirconia (PS-ZrO2) have been investigated in detail by means of homologue series retention studies and studies of a variety of nonpolar aromatic positional isomers. This material has been compared to polybutadiene-coated zirconia, octadecyl- and phenyl-bonded silica, and polymer-based reversed phases. In addition, the separations of a wide variety of compound classes on PS-ZrO2 were compared with those on other aromatic and aliphatic RPLC phases. The PS-ZrO2 material exhibits substantial differences in selectivity toward nonpolar and polar analytes as compared to other phases, especially with respect to polybutadiene-coated zirconia (PBD-ZrO2). On PS-ZrO2, polynuclear aromatic hydrocarbons (PAHs) are retained much more than are alkylbenzenes, whereas on PBD-ZrO2 the opposite is observed. In addition, PS-ZrO2 has much greater selectivity than does PBD-ZrO2 for the separation of structural isomers which differ in the position of phenyl groups. In general, even though the carbon content of PS-ZrO2 is much lower than that of conventional reversed-phase materials, such as octadecyl-bonded silica (C18-SiO2), polar analytes exhibit sufficient retention and differential selectivity on PS-ZrO2 that resolution comparable to that on C18-SiO2 can be obtained but with substantially improved analysis times.

Chromatography, Liquid↗

PubMed2000

Altered regulation of cardiac muscle contraction by troponin T mutations that cause familial hypertrophic cardiomyopathy.

To study the effect of troponin (Tn) T mutations that cause familial hypertrophic cardiomyopathy (FHC) on cardiac muscle contraction, wild-type, and the following recombinant human cardiac TnT mutants were cloned and expressed: I79N, R92Q, F110I, E163K, R278C, and intron 16(G(1) --> A) (In16). These TnT FHC mutants were reconstituted into skinned cardiac muscle preparations and characterized for their effect on maximal steady state force activation, inhibition, and the Ca(2+) sensitivity of force development. Troponin complexes containing these mutants were tested for their ability to regulate actin-tropomyosin(Tm)-activated myosin-ATPase activity. TnT(R278C) and TnT(F110I) reconstituted preparations demonstrated dramatically increased Ca(2+) sensitivity of force development, while those with TnT(R92Q) and TnT(I79N) showed a moderate increase. The deletion mutant, TnT(In16), significantly decreased both the activation and the inhibition of force, and substantially decreased the activation and the inhibition of actin-Tm-activated myosin-ATPase activity. ATPase activation was also impaired by TnT(F110I), while its inhibition was reduced by TnT(R278C). The TnT(E163K) mutation had the smallest effect on the Ca(2+) sensitivity of force; however, it produced an elevated activation of the ATPase activity in reconstituted thin filaments. These observed changes in the Ca(2+) regulation of force development caused by these mutations would likely cause altered contractility and contribute to the development of FHC.

Amino Acid Sequence↗

PubMed2000

Echogenicity of liver metastases is an independent prognostic factor after potentially curative treatment.

HYPOTHESIS: Intraoperative echogenic appearance of liver metastases from colorectal cancer is a prognostic factor of outcome after curative treatment. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Department of Surgery at a university hospital. PATIENTS: One hundred forty-three consecutive patients with hepatic metastases from colorectal cancer who underwent liver resection with curative intent between 1992 and 1998. INTERVENTION: Curative treatment was achieved by liver resection alone, liver resection plus edge cryotherapy, or liver resection plus cryotherapy to lesions not amenable to further resection. In patients with more than 2 lesions, a hepatic artery catheter was placed for regional chemotherapy. MAIN OUTCOME MEASURES: The echogenic appearance of the liver metastases was assessed by intraoperative ultrasound by a single person throughout the study using a 5-MHz ultrasound probe. The findings were prospectively entered into the database. RESULTS: Fifty-four percent of patients had hyperechoic metastases. This group had significantly longer overall (log rank, P<.001) and recurrence-free survival (log rank, P =.004) compared with patients who had hypoechoic metastases (36%). A significantly higher percentage of mucin-secreting tumors were found in the hypoechoic patient group (chi(2), P =.001). Dukes stage of the primary tumor (P =.02), echogenicity of the liver secondaries (P =.04), and diameter of the largest resected metastasis (P =.01) were independent prognostic factors for recurrence-free survival in the Cox regression model. CONCLUSION: These results support the hypothesis that echogenicity of liver metastases from colorectal cancer is an independent prognostic factor of outcome after curative resection.

Colorectal Neoplasms↗

PubMed2000

In vitro culture of rat pre-antral follicles with emphasis on follicular interactions.

The present study was designed to determine whether rat pre-antral follicles can grow under in-vitro conditions. Emphasis is on whether follicular interaction is involved in in-vitro follicle culture, and furthermore its role in follicular development has been assessed. Pre-antral follicles were isolated mechanically from 10-day old rat ovaries. They were divided into small (50 microm < diameter < 100 microm) and large (120 microm < diameter < 200 microm) pre-antral follicles and cultured individually or in groups for 6 days in medium with or without fetal calf serum (FCS). Based on morphological criteria, large pre-antral follicles cultured in groups in serum-free medium had significantly higher survival rates than those cultured individually. In the presence of FCS, no significant difference was detected with respect to the survival. However, the large pre-antral follicles cultured in groups had a significantly greater increase in diameter than those cultured individually. Furthermore, follicles cultured in groups in FCS-containing medium exhibited significantly more follicular cell proliferation than those in serum-free medium, based on DNA measurement. The present culture system (with or without FCS) proved to be insufficient for small pre-antral follicles to stimulate growth comparable to that of large pre-antral follicles. The transmission electron microscopical (TEM) study revealed the ultrastructural differences between follicles cultured in FCS-containing and serum-free media. Taken together, the results suggest that interfollicular factors are involved in follicle development in vitro, which especially at the early folliculogenesis stage plays a positive role in terms of follicular growth as well as survival. The present culture model allows further investigation of factors that regulate early folliculogenesis.

Animals↗

PubMed2000

The diagnosis value and its implication of impulse oscillometry in obstructive sleep apnea syndrome patients.

The change of measurements of impulse oscillometry (IOS) in obstructive sleep apnea syndrome (OSAS) patients and its mechanism were observed. The respiratory impedance was measured by using IOS technique and polysomnography (PSG) was monitored synchronously in 36 OSAS patients, 14 patients with chronic obstructive pulmonary disease (COPD) and 12 normal controls. Results showed that R20 in OSAS group was significantly higher than in COPD group and control group (P < 0.01). R5-R20 in OSAS group was lower than that in COPD group, but significantly higher than that in control group (P < 0.01). The levels of R20 and R5-R20 were positively correlated with severity degree of the disease. In addition, apnea-hyponea index (AHI) was positively correlated with R5 and R20 with the correlation index (r)being 0.66 and 0.86 respectively. The lowest SO2 was negatively correlated with R5 and R5-R20, with r being -0.66 and -0.79 respectively. The mean SO2 was negatively correlated with R5 and R5-R20 with r being -0.81 and -0.69 respectively. IOS technique could be used as a valuable tool for assessing the degree of upper airway obstruction in the patients with OSAS, and could help to explore its pathological mechanism.

Adult↗

PubMed2000

Investigation of the distribution and changes of VLDLR subtype in fibrotic cardiac muscles.

Very low-density lipoprotein receptor (VLDLR) is the major receptor with which cells can uptake the triacylglycerol from blood. It is divided into two subtypes according to presence of O-linked sugar domain located in the VLDLR receptor immediately outside of the membrane. Type I VLDLR contains the O-link domain, while type II has no such domain. The type I VLDLR are mainly found on the surface of human myocardial cells. The result of our quantitative polymerase chain reaction on the normal and fibrotic cardiac muscles showed that both subtypes and expression level of VLDLR on the myocardial cell surface did not vary significantly between the normal and the fibrotic cardiac muscles despite the presence of malfunction due to fibrosis. This finding suggests that fibrosis doesn't exert significant influence on the subtype and the expression of VLDLR on the surface of myocardial cells. Such inconsistence with the changes found in other fibrotic tissues is awaiting further studies.

Fibrosis↗

PubMed2000

Refractive Error Study in Children: results from Shunyi District, China.

PURPOSE: To assess the prevalence of refractive errors and vision impairment in school-age children in Shunyi District, northeast of Beijing, the Peoples Republic of China. METHODS: Random selection of village-based clusters was used to identify a sample of children 5 to 15 years of age. Resident registration books were used to enumerate eligible children in the selected villages and identify their current school. Ophthalmic examinations were conducted in 132 schools on children from 29 clusters during May 1988 to July 1998, including visual acuity measurements, cycloplegic retinoscopy, cycloplegic autorefraction, ocular motility evaluation, and examination of the external eye, anterior segment, media, and fundus. Independent replicate measurements of all children with reduced vision and a sample of those with normal vision were done for quality assurance monitoring in three schools. RESULTS: A total of 6,134 children from 4,338 households were enumerated, and 5,884 children (95.9%) were examined. The prevalence of uncorrected, presenting, and best visual acuity 0.5 (20/40) or worse in at least one eye was 12.8%, 10.9%, and 1.8%, respectively; 0.4% had best visual acuity 0.5 or worse in both eyes. Refractive error was the cause in 89.5% of the 1,236 eyes with reduced vision, amblyopia in 5%, other causes in 1.5%, with unexplained causes in the remaining 4%. Myopia -0.5 diopter or less in either eye was essentially absent in 5-year-old children, but increased to 36.7% in males and 55.0% in females by age 15. Over this same age range, hyperopia 2 diopters or greater decreased from 8.8% in males and 19.6% in females to less than 2% in both. Females had a significantly higher risk of both myopia and hyperopia. CONCLUSIONS: Reduced vision because of myopia is an important public health problem in school-age children in Shunyi District. More than 9% of children could benefit from prescription glasses. Further studies are needed to determine whether the upward trend in the prevalence of myopia continues far beyond age 15 and whether the development of myopia is changing for more recent birth cohorts.

Adolescent↗

PubMed2000

Refractive Error Study in Children: sampling and measurement methods for a multi-country survey.

PURPOSE: The Refractive Error Study in Children was designed to assess the prevalence of refractive error and vision impairment in children of different ethnic origins and cultural settings. METHODS: Population-based cross-sectional samples of children 5 to 15 years of age were obtained through cluster sampling. Presenting, uncorrected, and best-corrected visual acuity, along with refractive error under cycloplegia, were the main outcome measures. Amblyopia and other causes of uncorrectable vision impairment were determined. RESULTS: Study design and sample size calculations, survey enumeration and ophthalmic examination methods, quality assurance monitoring, and da ta analyses and statistical methods are described. CONCLUSIONS: The study design, sample size, and measurement methods ensure that the prevalence of age-specific and sex-specific refractive error can be estimated with reasonable accuracy in the target populations. With commonality of methods, a comparison of findings between studies in different ethnic origins and cultural settings is possible.

Adolescent↗

PubMed2000

Losses of chromosomes 1p and 3q are early genetic events in the development of sporadic pheochromocytomas.

Despite several loss of heterozygosity studies, a comprehensive genomic survey of pheochromocytomas is still lacking. To identify DNA copy number changes which might be important in tumor development and progression and which may have diagnostic utility, we evaluated genetic aberrations in 29 sporadic adrenal and extra-adrenal pheochromocytomas (19 clinically benign tumors and 10 malignant lesions). Comparative genomic hybridization was performed using directly fluorochrome-conjugated DNA extracted from frozen (16) and paraffin-embedded (13) tumor tissues. The most frequently observed changes were losses of chromosomes 1p11-p32 (86%), 3q (52%), 6q (34%), 3p, 17p (31% each), 11q (28%), and gains of chromosomes 9q (38%) and 17q (31%). No amplification was identified and no difference between adrenal and extra-adrenal tumors was detected. Progression to malignant tumors was strongly associated with deletions of chromosome 6q (60% versus 21% in clinically benign lesions, P = 0.0368) and 17p (50% versus 21%). Fluorescence in situ hybridization confirmed the comparative genomic hybridization data of chromosomes 1p, 3q, and 6q, and revealed aneuploidy in some tumors. Our results suggest that the development of pheochromocytomas is associated with specific genomic aberrations, such as losses of 1p, 3q, and 6q and gains of 9q and 17q. In particular, tumor suppressor genes on chromosomes 1p and 3q may be involved in early tumorigenesis, and deletions of chromosomes 6q and 17p in progression to malignancy.

Adult↗

PubMed2000

Genomic alterations in well-differentiated gastrointestinal and bronchial neuroendocrine tumors (carcinoids): marked differences indicating diversity in molecular pathogenesis.

Neuroendocrine tumors (carcinoids) are a heterogeneous group of neoplasms arising from the diffuse neuroendocrine system. Genetic changes underlying their tumorigenesis are primarily unknown. We used comparative genomic hybridization to screen 32 well-differentiated neuroendocrine tumors (21 gastrointestinal and 11 bronchial) and three associated metastases for genomic alterations. There were striking differences of genomic imbalances between the two subgroups of neuroendocrine tumors. Losses of chromosome 18q and 18p were shown in eight (38%) and seven (33%), respectively, out of 21 gastrointestinal tumors and in none of the 11 bronchial tumors. Conversely, deletions of 11q occurred in four of 11 (36%) bronchial tumors but only in one gastrointestinal tumor. These comparative genomic hybridization findings were confirmed by interphase cytogenetics. Our data indicate that neuroendocrine tumors of the two subgroups develop via different molecular pathways. Inactivation of one or several tumor suppressor genes on chromosome 18 may be important for the biological behavior of gastrointestinal tumors, whereas gene inactivation on 11q seems to be associated with tumor development of the bronchi.

Adult↗

PubMed2000

Conformation, independent of charge, in the R domain affects cystic fibrosis transmembrane conductance regulator channel openings.

The R domain of cystic fibrosis transmembrane conductance regulator (CFTR), when phosphorylated, undergoes conformational change, and the chloride channel opens. We investigated the contribution of R domain conformation, apart from the changes induced by phosphorylation, to channel opening, by testing the effect of the peptidyl-prolyl isomerase, cyclophilin A, on the CFTR channel. When it was applied after the channel had been opened by PKA phosphorylation, cyclophilin A increased the open probability of wild-type CFTR (from P(o) = 0.197 +/- 0.010 to P(o) = 0.436 +/- 0. 029) by increasing the number of channel openings, not open time. Three highly conserved proline residues in the R domain, at positions 740, 750, and 759, were considered as candidate targets for cyclophilin A. Mutations of these prolines to alanines (P3A mutant) resulted in a channel unresponsive to cyclophilin A but with pore properties similar to the wild type, under strict control of PKA and ATP, but with significantly increased open probability (P(o) = 0.577 +/- 0.090) compared to wild-type CFTR, again due to an increase in the number of channel openings and not open time. Mutation of each of the proline residues separately and in pairs demonstrated that all three proline mutations are required for maximal P(o). When P3A was expressed in 293 HEK cells and tested by SPQ assay, chloride efflux was significantly increased compared to cells transfected with wild-type CFTR. Thus, treatments favoring the trans-peptidyl conformation about conserved proline residues in the R domain of CFTR affect openings of CFTR, above and beyond the effect of PKA phosphorylation.

Alanine↗

PubMed2000

Influence of modified soils on the removal of diesel fuel oil from water and the growth of oil degradation micro-organism.

Three soils were modified with two kinds of cationic surfactants in order to increase their sorptive capabilities for organic contaminants. Sorption of diesel fuel oil in water by these modified soils had been investigated. Modified soils can effectively sorb diesel fuel oil from water. The sorption capability of modified soils is: HDTMA-black soil > HDTMA-yellow brown soil > HDTMA-red soil > TMA-black soil > TMA-yellow brown soil > TMA-red soil. Sorption of diesel fuel oil by natural soils and HDTMA modified soils is via partition, the sorption isotherms can be expressed by Henry equation, and logK(SOM) is 2.42-2.80, logK(HDTMA) is 3.37-3.60. Sorption isotherms of TMA modified soils can be expressed by Langmuir equation, the saturation sorption capacities are 1150 (TMA-black soil), 750 (TMA-yellow-brown soil), 171 mg/kg (TMA-red soil), respectively. A diesel fuel oil degradation micro-organism (Pseudomonas sp.) was isolated in the lab. To test the influence of the modified soils on the micro-organism, various growth curves of Pseudomonas in different conditions were drawn. Pseudomonas can grow very well with natural soils and TMA modified soils. The acclimation period of Pseudomonas is reduced. As to HDTMA modified soils, HDTMA loading amount is very important. When HDTMA loading amount is no higher than 0.5 CEC, the micro-organism can grow very well after a long acclimation period.

Absorption↗

PubMed2000

Photooxidation mechanism of nitrogen-containing compounds at TiO2/H2O interfaces: an experimental and theoretical examination of hydrazine derivatives.

The photocatalytic oxidation of oxalyldihydrazide, N,N'-bis(hydrazocarbonyl)hydrazide, N,N'-bis(ethoxycarbonyl)hydrazide, malonyldihydrazide, N-malonyl-bis[(N'-ethoxycarbonyl)hydrazide] was examined in aqueous TiO2 dispersions under UV illumination. The photomineralization of nitrogen and carbon atoms in the substrates into N2 gas, NH4+ (and/or NO3-) ions, and CO2 gas was determined by HPLC and GC analysis. The formation of carboxylic acid intermediates also occurred in the photooxidation process. The photocatalytic mechanism is discussed on the basis of the experimental results, and with molecular orbital (MO) simulation of frontier electron density and point charge. Substrate carbonyl groups readily adsorb on the TiO2 surface, and the bonds between carbonyl group carbon atoms and adjacent hydrazo group nitrogen atoms are cleaved predominantly in the initial photooxidation process. The hydrazo groups were photoconverted mainly into N2 gas (in mineralization yields above 70%) and partially to NH4 ions (below 10%). The formation of NO3- ions was scarcely recognized.

Catalysis↗