Biomedical subjects

M Hattori

Publications and source records attributed to M Hattori.

At least 109 records · Page 6Linked to original sources

PubMed2000

A peculiar vacuolization in the kidney transplant of a child treated with tacrolimus.

Tacrolimus (TAC) is a useful immunosuppressive agent in the prevention of rejection. However, the blood level between its therapeutic and toxic levels is narrow such that its nephrotoxicity is a problem. Moreover, its bioavailability and pharmacokinetics are highly variable. We experienced a case of acute nephrotoxicity, in which the blood level rose about 10 times above the expected level. We found a peculiar vacuolization in the transplant biopsy specimen. This change showed a marked vacuolization of the tubular cells, suggestive of acute nephrotoxicity by TAC.

Adolescent↗

PubMed2000

Phenotypic characteristics and cyclin-dependent kinase inhibitors repression in hyperplastic epithelial pathology in idiopathic focal segmental glomerulosclerosis.

Hyperplastic glomerular epithelial lesion is an important determinant of the progression of idiopathic focal segmental glomerulosclerosis (FGS). The proliferation and differentiation of glomerular epithelial cells and parietal epithelial cells (PECs) are regulated differently by cyclin and cyclin-dependent kinase inhibitors (CKIs) during nephrogenesis. To access the cellular mechanism underlying epithelial hyperplasia in the development of FGS, the present study applied immunohistochemistry to 21 cases of FGS to demonstrate expression of cell-cycle molecules and phenotypic characterization in proliferative epithelial lesions in FGS. The materials included segmental sclerosis (18.1%), which was divided into monolayer epithelial lesions (64.6%) and cellular lesions (35.4%). All of the cellular lesions expressed cytokeratin, frequently with Ki-67 (82.4%) and less frequently with cyclin A (17.7%), but were invariably negative for podocyte markers (PHM-5 and synaptopodin) and CKIs (p27kip1 and p57kip2). Podocytes in nonsclerotic tuft in the same glomeruli with cellular lesions strongly expressed CKIs and podocyte markers. Moreover, electron microscopy showed that some large proliferating cells with prominent nucleoli have a broad cell base attached to Bowman's capsule. These cells have cilia and a junctional complex with neighboring hyperplastic cells, some of which directly cover the glomerular basement membrane. This suggests that cellular lesions are of PEC origin. Monolayer epithelial lesions also exclusively exhibited a PEC phenotype with reciprocal expression of podocyte markers and cytokeratin. In addition, CKIs are weakly expressed in monolayer epithelial lesions, suggesting a re-entry of cell-cycle quiescent. In conclusion, proliferation of PEC, sustained by repression of CKIs in nature and simultaneous activation of cyclin A, is the actual molecular background to the cellular lesions in FGS. Cellular lesions may result in monolayer epithelial lesions that retain the PEC phenotype and enter a common pathway to glomerulosclerosis.

Adolescent↗

PubMed2000

Sequential observation of liver cell regeneration after massive hepatic necrosis in auxiliary partial orthotopic liver transplantation.

The morphogenesis of hepatocytes after massive hepatic necrosis to recovery through liver cell regeneration has not been fully understood. Sequential biopsies were performed on the native liver of a 22-year-old man who underwent auxiliary partial orthotopic liver transplantation 1 month after fulminant hepatitis. Auxiliary partial orthotopic liver transplantation was successful, and the biopsy samples permitted us to examine the regenerating process of hepatocytes after massive necrosis. At the time of auxiliary partial orthotopic liver transplantation (postoperative day 0), 95% of hepatocytes were lost and a few ductules were found in the portal areas. The ductules stained with cytokeratin 19. At postoperative day 7, the ductules began to increase in size and number and became dilated over a period of 1 month, when individual hepatocytes with clear cytoplasm appeared from the ductules. As the differentiation of hepatocytes increased, the expression of cytokeratin 19 was found to decrease. From 2 to 3 months, all of the ductules were transformed into hepatocytes, and they began to form round cell clusters. From 3 to 6 months, the round cell clusters became organized into trabecula with fibrosis. From 6 to 12 months, a lobular architecture was established, and by 14 months, the necrotic liver was fully recovered to normal. This study by examination of sequential biopsies demonstrates the progression of the regenerating process from total hepatic necrosis to complete recovery.

Adult↗

PubMed2000

Speciation of protein-binding zinc and copper in human blood serum by chelating resin pre-treatment and inductively coupled plasma mass spectrometry.

A method for the speciation of zinc and copper binding with proteins in human serum was explored by chelating resin (Chelex-100) pre-treatment and inductively coupled plasma mass spectrometry (ICP-MS). It was shown by a SEC (size-exclusion chromatography)-ICP-MS system that albumin-zinc and albumin-copper (loosely-bound species) could be selectively removed from serum by adsorption on the Chelex-100 resin after the chelating resin pre-treatment, while alpha 2-macroglobulin-zinc and ceruloplasmin-copper (firmly-bound species) remained in the serum. The zinc and copper bound with alpha 2-macroglobulin and ceruloplasmin, respectively, were then determined by ICP-MS after batch treatment of the serum samples with the Chelex-100 resin. In addition, the total concentrations of zinc and copper were also determined by ICP-MS after a 20-fold dilution with 0.1 M HNO3. The albumin-zinc and -copper were estimated as the differences between the concentrations of total and firmly-bound species. The present batch pre-treatment method was applied to the speciation analysis of zinc and copper binding with proteins in sera donated from 25 healthy volunteers as well as from a pregnant woman and a myelodysplastic syndrome patient. The observed concentrations of alpha 2-macroglobulin-zinc and ceruloplasmin-copper were in the ranges 109-202 ng ml-1 (12.4-31.3% of total zinc) and 513-880 ng ml-1 (90.6-99.7% of total copper), respectively. The present method is simple (only addition of the chelating resin and centrifugation is required) and reproducible (average RSD = 2% for alpha 2-macroglobulin-zinc and 1% for ceruloplasmin-copper in intra-assay measurements, and 5% for alpha 2-macroglobulin-zinc and 4% for ceruloplasmin-copper in inter-assay measurements), and there is less risk of contamination during separation.

Blood Proteins↗

PubMed2000

Histological increase in inflammatory infiltrate in sun-exposed skin of female subjects: the possible involvement of matrix metalloproteinase-1 produced by inflammatory infiltrate on collagen degradation.

To investigate morphological changes occurring during cutaneous photoageing, a correlation between the number of infiltrating cells in the dermis and the degree of collagen damage was examined using sections from clinically normal chronically sun-exposed and sun-protected skin of Japanese female subjects. Haematoxylin and eosin-stained sections from 134 sun-exposed (subjects aged 3-82 years) and 73 sun-protected (subjects aged 1-86 years) areas demonstrated a predominant lymphoid cell and to a lesser extent histiocyte infiltration. The mean +/- SD number of lymphoid cells and histiocytes in the sun-exposed skin sections (427.0+/-192.2 and 147.8+/-83.3 cells/mm2, respectively) was significantly higher than in the sun-protected skin sections (292.6+/-98.3 and 125.9+/-59.0 cells/mm2, respectively) (P < 0.001 and P < 0.05, respectively), and the number of lymphoid cells in the sun-exposed skin sections increased significantly with age up to 50 years (r = 0.400, P < 0.001). Sun-exposed skin sections with severe collagen degeneration had a significantly higher number of lymphoid cells than those with slightly degenerated collagen (mean 626.3 vs. 482.4 cells/mm2, P < 0.01). The mean count of mast cells in sun-exposed skin was 202.0 cells/mm2; this did not vary with the age of the subjects or the level of collagen damage. Immunohistochemical studies using 24 frozen sections identified most of the lymphoid cells infiltrating sun-exposed skin as memory T lymphocytes (CD3+, CD4+ and CD45RO+). The number of cells which displayed immunoreactivity to matrix metalloproteinase (MMP)-1 in the sun-exposed skin sections was significantly higher than in the sun-protected skin sections (mean 170.2 vs. 113.6 cells/mm2, P < 0.05). Among these cells were observed CD3 and MMP-1 double-stained T lymphocytes, and T lymphocytes contacting MMP-1-positive cells. These morphological observations suggest that T lymphocytes infiltrating photodamaged skin may play a part in the degeneration and reduction of collagen through MMP-1 activity.

Adolescent↗

PubMed2000

Hepatoprotective effect of Apocynum venetum and its active constituents.

The leaves of Apocynum venetum L. are used as a tea material in north China and Japan. A water extract (500 mg/kg/day, one week administration) of the leaves of A. venetum showed protective effects against carbon tetrachloride (CCl4, 30 microliters/mouse) or D-galactosamine (D-GalN, 700 mg/kg)/lipopolysaccharide (LPS, 20 micrograms/kg)-induced liver injury in mice. Tumor necrosis factor-alpha (TNF-alpha) secreted from LPS-stimulated macrophages is the most crucial mediator in the D-GalN/LPS-induced liver injury model. The extract had no significant inhibition on the increase of serum TNF-alpha (1169 +/- 132 pg/ml vs. 1595 +/- 314 pg/ml of control), but exhibited a complete inhibition at the concentration of 100 micrograms/ml on TNF-alpha (100 ng/ml)-induced cell death in D-GalN (0.5 mM)-sensitized mouse hepatocytes. Further activity-guided fractionation resulted in the isolation of fifteen flavonoids viz. (-)-epicatechin (1), (-)-epigallocatechin (2), isoquercetin (3), hyperin (4), (+)-catechin (5), (+)-gallocatechin (6), kaempferol-6'-O-acetate (7), isoquercetin-6'-O-acetate (8), catechin-[8,7-e]-4 alpha-(3,4-dihydroxpyhenyl)-dihydro-2(3H)-pyranone (9), apocynin B (10), apocynin A (11), cinchonain Ia (12), apocynin C (13), apocynin D (14) and quercetin (15). All the compounds showed inhibitory effects on TNF-alpha-induced cell death with different intensities. The flavonol glycosides 3, 4, 7 and 8 and the phenylpropanoid-substituted flavan-3-ols 11 and 12 showed potent inhibitory effects on TNF-alpha-induced cell death with IC50 values of 37.5, 14.5, 31.2, 55.1, 71.9 and 41.2 microM, respectively. In contrast, the clinically used 5 and its analogues 1, 2 and 6 showed apparent activity only at 80 microM. These flavonoids appeared to be the hepatoprotective principles of the leaves of A. venetum. The hepatoprotective effects exhibited by the extract and its constituents suggest a validation of the leaves as a tea material.

Animals↗

PubMed2000

Comparison of outer membrane protein genes omp and pmp in the whole genome sequences of Chlamydia pneumoniae isolates from Japan and the United States.

Chlamydia pneumoniae is a widespread pathogen of the respiratory tract that is also associated with atherosclerosis. The whole genome sequence was determined for a Japanese isolate, C. pneumoniae strain J138. The sequence predicted a variety of genes encoding outer membrane proteins (OMPs) including ompA and porB, another 10 predicted omp genes, and 27 pmp genes. All were detected in the whole genome sequence of strain CWL029, a strain isolated and sequenced in the United States. A comparative study of the OMPs of the two strains revealed a nucleotide sequence identity of 89.6%-100% (deduced amino acid sequence identity, 71.1%-100%). The overall genomic organization and location of genes are identical in both strains. Thus, a few unique sequences of the OMPs may be essential for specific attributes that define the differential biology of two C. pneumoniae strains.

Bacterial Outer Membrane Proteins↗

PubMed2000

Clinical significance of major and minor bcr/abl chimeric transcripts in essential thrombocythemia.

BACKGROUND: Contradictory results have been reported in terms of detecting bcr/abl transcripts in patients with essential thrombocythemia. The aim of this study was to investigate whether the bcr/abl transcript could be found in patients with essential thrombocythemia (ET). METHODS: The bcr/abl transcript was amplified by the RT-nested PCR method using RNA extract from leukocytes taken from 14 essential thrombocythemia patients. The amplified DNAs were electrophoresed in 1% agarose and visualized with ethidium bromide. The DNA bands associated with the bcr/abl transcript were then extracted and followed by DNA sequence analysis. RESULTS: Major bcr/abl transcripts of the b3a2 type and minor ones of the e1a2 type were found in one and two ET patients, respectively. The incidence of bcr/abl transcripts was 21.4% (three of 14 patients). CONCLUSION: Our experiments confirmed that bcr/abl transcripts are present in some patients with essential thrombocythemia.

Adult↗

PubMed2000

Analysis of the RNase H activity by fluorescence resonance energy transfer.

The RNase H activity of HIV-1 reverse transcriptase was examined using chemically synthesized deoxyribo.ribo-oligonucleotide hybrid duplex labeled with the fluorescence donor at the 5'-end and with the fluorescence acceptor at the 3'-end of DNA strand as a substrate. Fluorescence resonance energy transfer (FRET) between these fluorescent dyes was used to analyze the rate of the enzymatic reaction. Under excitation of the donor dye, that is 6-carboxyfluorescein (6-FAM), at 490 nm, the increase of the fluorescence resulting from the acceptor dye, that is 6-carboxytetramethylrhodamine (TAMRA), at 578 nm, was observed depending on the degradation of DNA.RNA hybrid duplex. This method can be introduced into the high throughput screening of the inhibitors against the RNase H activity for anti-HIV drug.

Base Sequence↗

PubMed2000

Comparative genome analysis of the mouse imprinted gene impact and its nonimprinted human homolog IMPACT: toward the structural basis for species-specific imprinting.

Mouse Impact is a paternally expressed gene encoding an evolutionarily conserved protein of unknown function. Here we identified IMPACT, the human homolog of Impact, on chromosome 18q11. 2-12.1, a region syntenic to the mouse Impact locus. IMPACT was expressed biallelically in brain and in various tissues from two informative fetuses and in peripheral blood from an informative adult. To reveal the structural basis for the difference in allelic expression between the two species, we elucidated complete genome sequences for both mouse Impact ( approximately 38 kb) and human IMPACT ( approximately 30 kb). Sequence comparison revealed that the two genes share a well-conserved exon-intron organization but bear significantly different CpG islands. The mouse island lies in the first intron and contains characteristic tandem repeats. Furthermore, this island serves as a differentially methylated region (DMR) consisting of a hypermethylated maternal allele and an unmethylated paternal allele. Intriguingly, this intronic island is missing from the nonimprinted human IMPACT, whose sole CpG island spans the first exon, lacks any apparent repeats, and escapes methylation on both chromosomes. These results suggest that the intronic DMR plays a role in the imprinting of Impact.

Alleles↗

PubMed2000

Differential expression of renal AGE-receptor genes in NOD mice: possible role in nonobese diabetic renal disease.

BACKGROUND: Nonobese diabetic mice (NOD) are prone to glomerular pathology, which is accelerated with the onset of diabetes. Advanced glycation end product (AGE) interactions with AGE-receptors (AGE-Rs) in kidneys can contribute to glomerular injury and diabetic nephropathy (DN). The significant elevation in kidney AGE deposits noted in prediabetic NOD mice suggested that delayed AGE turnover in this model may contribute to its propensity toward DN. METHODS: To explore whether excess tissue AGE was linked to altered AGE-R status in the kidney, mRNA/protein expression, and of several AGE-Rs [AGE-R1, AGE-R2, AGE-R3, scavenger receptor II (ScR-II), and receptor for AGE (RAGE)], was determined in renal cortex and in mesangial cells (MCs) isolated from ND-, D-NOD, and ILE mice (N = 20 per group). Ligand binding, receptor site number, and affinity were determined in MCs from the same mouse groups. RESULTS: Prediabetic NOD kidney AGE-R1 mRNA and protein level were threefold lower than that of ILE mice (P < 0.01), while AGE-R3 mRNA was enhanced by twofold (P < 0.05) and AGE-R2, RAGE, and ScR-II mRNA remained close to normal (ILE). The onset of diabetes in NOD mice, while enhancing AGE-R1 mRNA expression by approximately twofold, failed to raise it above the normal (ILE) level, despite increases in tissue, and serum AGE. The latter was associated with higher elevation in AGE-R3 (sixfold, P < 0.05), RAGE (twofold, P = NS), and ScR-II mRNA (2. 8-fold, P = NS) above control. MCs from prediabetic NOD mice showed a threefold lower level of AGE-R1 mRNA (P < 0.02 vs. ILE) and AGE-R1-protein, and AGE-binding activity (<40% of control ILE). In contrast, AGE-R3 mRNA was enhanced (twofold), while AGE-R2 showed no change. Cultured ND-NOD MCs displayed only one fourth of the AGE-binding sites/cell present on ILE MCs (1.6 x 10(6) vs. 6.6 x 10(6), P < 0.05), which after the onset of diabetes rose to the normal range (7.0 x 10(6)/cell), but failed to exceed it. CONCLUSIONS: Reduced AGE-R1 gene expression in this strain may contribute to delayed AGE removal from and early AGE deposition in kidney tissues. This may act as a trigger for those AGE-R genes involved in growth-promoting changes, leading to DN in this strain.

Animals↗

PubMed2000

Rap1 is a potent activation signal for leukocyte function-associated antigen 1 distinct from protein kinase C and phosphatidylinositol-3-OH kinase.

To identify the intracellular signals which increase the adhesiveness of leukocyte function-associated antigen 1 (LFA-1), we established an assay system for activation-dependent adhesion through LFA-1/intercellular adhesion molecule 1 ICAM-1 using mouse lymphoid cells reconstituted with human LFA-1 and then introduced constitutively active forms of signaling molecules. We found that the phorbol myristate acetate (PMA)-responsive protein kinase C (PKC) isotypes (alpha, betaI, betaII, and delta) or phosphatidylinositol-3-OH kinase (PI 3-kinase) itself activated LFA-1 to bind ICAM-1. H-Ras and Rac activated LFA-1 in a PI 3-kinase-dependent manner, whereas Rho and R-Ras had little effect. Unexpectedly, Rap1 was demonstrated to function as the most potent activator of LFA-1. Distinct from H-Ras and Rac, Rap1 increased the adhesiveness independently of PI 3-kinase, indicating that Rap1 is a novel activation signal for the integrins. Rap1 induced changes in the conformation and affinity of LFA-1 and, interestingly, caused marked LFA-1/ICAM-1-mediated cell aggregation. Furthermore, a dominant negative form of Rap1 (Rap1N17) inhibited T-cell receptor-mediated LFA-1 activation in Jurkat T cells and LFA-1/ICAM-1-dependent cell aggregation upon differentiation of HL-60 cells into macrophages, suggesting that Rap1 is critically involved in physiological processes. These unique functions of Rap1 in controlling cellular adhesion through LFA-1 suggest a pivotal role as an immunological regulator.

Animals↗

PubMed2000

High prevalence of antineutrophil cytoplasmic antibody positivity in childhood onset Graves' disease treated with propylthiouracil.

Propylthiouracil (PTU)-induced antineutrophil cytoplasmic antibody (ANCA)-related vasculitis and nephritis were recently reported in about 30 patients with hyperthyroidism. The objective of this study was to clarify the prevalence of ANCA and the relationship between ANCA and thyroid antibodies in children with Graves' disease. Titers of myeloperoxidase (MPO)-ANCA in sera of 51 patients with childhood onset Graves' disease (16 before treatment, 25 and 10 treated with PTU and methimazole, respectively) were measured by enzyme-linked immunosolvent assay. Antithyroglobulin antibodies (TGAbs) and antithyroperoxidase antibodies (TPOAbs) were also measured by RIA in 25 PTU-treated patients. No patients had clinical manifestations of vasculitis and nephritis. MPO-ANCA was positive in 6.7% of patients before treatment and in 64.0% of those treated with PTU and in none of those treated with methimazole. MPO-ANCA had a significantly positive correlation with TGAbs (P < 0.05) and no significant correlation with TPOAbs. These findings show the high prevalence of the MPO-ANCA positivity in PTU-treated childhood onset Graves' disease, suggesting that PTU may not be preferred as the first line for the treatment of children with Graves' disease. The significant correlation between MPO-ANCA and TGAbs indicates that the severity of Graves' disease may be a factor responsible for the MPO-ANCA positivity. The cross-reactivity between MPO-ANCA and TPOAbs may not play a role in the high prevalence of MPO-ANCA in the patients exposed to PTU.

Adolescent↗

PubMed2000

Triterpenes from the spores of Ganoderma lucidum and their cytotoxicity against meth-A and LLC tumor cells.

Six new highly oxygenated lanostane-type triterpenes, called ganoderic acid gamma (1), ganoderic acid delta (2), ganoderic acid epsilon (3), ganoderic acid zeta (4), ganoderic acid eta (5) and ganoderic acid theta (6), were isolated from the spores of Ganoderma lucidum, together with known ganolucidic acid D (7) and ganoderic acid C2 (8). Their structures of the new triterpenes were determined as (23S)-7beta,15alpha,23-trihydroxy-3,11-dioxolanosta-8, 24(E)-diene-26-oic acid (1), (23S)-7alpha,15alpha23-trihydroxy-3,11-dioxolanosta-8, 24(E)-diene-26-oic acid (2), (23S)-3beta3,7beta, 23-trihydroxy-11,15-dioxolanosta-8,24(E)-diene-26-oic acid (3), (23S)-3beta,23-dihydroxy-7,11,15-trioxolanosta-8, 24(E)-diene-26-oic acid (4), (23S)-3beta,7beta,12beta,23-tetrahydroxy-11,15-dioxolanos ta-8,24(E)-diene-26-oic acid (5) and (23S)-3beta,12beta23-trihydroxy-7,11,15-trioxolanosta-8,24(E )-diene-26-oic acid (6), respectively, by chemical and spectroscopic means, which included the determination of a chiral center in the side chain by a modification of Mosher's method. The cytotoxicity of the compounds isolated from the Ganoderma spores was carried out in vitro against Meth-A and LLC tumor cell lines.

Animals↗

PubMed2000

Four mono-tetrahydrofuran ring acetogenins, montanacins B-E, from Annona montana.

Four novel mono-tetrahydrofuran (THF) acetogenins, montanacins B-E (1-4), were isolated from the ethanolic extract of the leaves of Annona montana. The structures of 1-4 were established by spectroscopic methods and their absolute stereochemistries were determined by the advanced Mosher ester method. Montancins D (3) and E (4) bear a non-adjacent tetrahydropyran (THP) ring along with a THF ring and are the most unusual type of acetogenins discovered so far.

Furans↗

PubMed2000

Biotransformation of a C-glycosylflavone, abrusin 2''-O-beta-D-apioside, by human intestinal bacteria.

After anaerobic incubation of abrusin 2''-O-beta-D-apioside (1) with a human fecal suspension, five metabolites were isolated and identified as abrusin (2), 1-(2',6'-dihydroxy-3',4'-dimethoxyphenyl)-3-(4''-hydroxyphenyl)propan-1- one (5), 5,6-dimethoxybenzene-1,3-diol (6), 3-(4'-hydroxyphenyl)propionic acid (7) and 3-phenylpropionic acid (8). However, methyl ether derivatives of abrusin (4'-O-methylabrusin and 4'-O-, 5-O-dimethylabrusin) resisted degradation under the same conditions.

Biotransformation↗

PubMed2000

Human intestinal bacteria capable of transforming secoisolariciresinol diglucoside to mammalian lignans, enterodiol and enterolactone.

Seven metabolites were isolated after anaerobic incubation of secoisolariciresinol diglucoside (1) with a human fecal suspension. They were identified as (-)-secoisolariciresinol (2), 3-demethyl-(-)-secoisolariciresinol (3), 2-(3-hydroxybenzyl)-3-(4-hydroxy-3-methoxybenzyl)butane-1,4-diol (4), didemethylsecoisolariciresinol (5), 2(3-hydroxybenzyl)-3-(3,4-dihydroxybenzyl)butane-1,4-diol (6), enterodiol (7) and enterolactone (8). Furthermore, two bacterial strains, Peptostreptococcus sp. SDG-1 and Eubacterium sp. SDG-2, responsible for the transformation of 1 to a mammalian lignan 7, were isolated from a human fecal suspension. The former transformed 2 to 3 and 5, as well as 4 to 6, and the latter transformed 5 to 6 and 7.

4-Butyrolactone↗

PubMed2000

Chemical modification of oleanene type triterpenes and their inhibitory activity against HIV-1 protease dimerization.

Oleanolic acid derivatives with different lengths of 3-O-acidic acyl chains were synthesized and evaluated for their inhibitory activity against HIV-1 protease. The lengths of the acidic chains were optimized to 6 and 8 carbons. Changing a 3-ester bond to an amide bond or dimerization of the triterpenes retained their inhibitory activity against HIV-1 protease. Introduction of an additional acidic chain to C-28 of oleanolic acid increased the inhibitory activity appreciably, though a derivative with only one acidic chain linked at C-28 also showed potent activity against HIV-1 protease. The inhibitory mechanism was proved directly by size exclusion chromatography to be inhibition of dimerization of the enzyme polypeptides. The ester bonds of the triterpene derivatives were found to be stable to lipase under mild alkaline conditions.

Chromatography, Gel↗