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1.
Matern Child Nutr ; 19(1): e13418, 2023 01.
Article in English | MEDLINE | ID: mdl-36069310

ABSTRACT

Poor complementary feeding (CF) challenges early childhood growth. We examined the trends and influencing factors of CF practices among children aged 6-23 months in Côte d'Ivoire. Using data from Demographic and Health Surveys (DHS, 1994-2011) and Multiple Indicator Cluster Surveys (MICS, 2000-2016), the trends and predictors of World Health Organization-United Nations International Children's Emergency Fund CF indicators including the timely introduction of complementary foods (INTRO), minimum meal frequency (MMF), minimum dietary diversity (MDD) and minimum acceptable diet (MAD) were determined. Using 2016 MICS data, we applied multivariate logistic regression models to identify factors associated with CF indicators. Between 1994 and 2016, the mean proportion of children aged 6-8 months achieving INTRO was 56.9% and increased by about 25% points since 2006. Over 2011-2016, the proportion of children aged 6-23 months meeting MMF, MDD and MAD increased from 40.2% to 47.7%, 11.3% to 26.0% and 4.6% to 12.5%, respectively. Older children and those from urban households had higher odds of meeting MDD and MAD. Maternal TV watching was associated with higher odds of meeting MDD. The secondary or higher education levels of mothers significantly predicted higher odds of meeting INTRO and MDD. Currently, breastfeeding was also positively associated with odds of meeting MMF and MAD. Children from poorer households had lower odds of meeting MMF, MDD and MAD. Despite the improvements, CF practices remain suboptimal in Côte d'Ivoire. Influencing factors associated with CF were distributed across individual, household and community levels, calling for future programmes and policies to implement multi-level strategies to improve young children's diet in Côte d'Ivoire.


Subject(s)
Feeding Behavior , Infant Nutritional Physiological Phenomena , Infant , Female , Child , Child, Preschool , Humans , Adolescent , Cote d'Ivoire/epidemiology , Socioeconomic Factors , Breast Feeding
4.
Diabet Med ; 33(10): 1399-405, 2016 10.
Article in English | MEDLINE | ID: mdl-26482027

ABSTRACT

AIMS: To test the hypothesis that 1-h plasma glucose in an oral glucose tolerance test is a better predictor of the development of diabetes than 2-h plasma glucose, independently of indices of insulin secretion or action in Japanese adults. METHODS: A historical cohort study was conducted in 1445 Japanese workers who did not have diabetes. The association between 1-h plasma glucose and the development of Type 2 diabetes was analysed. RESULTS: Overall, 95 of the study participants developed Type 2 diabetes during a mean follow-up of 4.5 years. The area under the receiver-operating characteristic curve for 1-h plasma glucose for future diabetes [0.88 (95% CI 0.84-0.91)] was greater than that for 2-h plasma glucose [0.79 (95% CI 0.74-0.84)], and for insulinogenic [0.73 (95% CI 0.68-0.78)] and disposition indices [0.79 (95% CI 0.74-0.84); P < 0.05]. Compared with the first quartile, the hazard ratio for future diabetes in the fourth quartile of 1-h plasma glucose was 42.5 [95% CI 5.7-315.2 (P < 0.05)] and the hazard ratio in the fourth quartile of 2-h plasma glucose was 4.4 [95% CI 1.8-10.8 (P < 0.05)], after adjustments for covariates including fasting plasma glucose. The significance of the elevated hazard ratio in the fourth quartile of 1-h plasma glucose was maintained after adjustments for 2-h plasma glucose, insulinogenic index or disposition index, whereas the elevation of the hazard ratio in the fourth quartile of 2-h plasma glucose was diminished and was no longer significant after adjustments for 1-h plasma glucose. CONCLUSIONS: One-hour plasma glucose had a greater association with the future development of Type 2 diabetes than did 2-h plasma glucose, independently of oral glucose tolerance test-derived indices of insulin action in a Japanese population.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 2/diagnosis , Prediabetic State/blood , Prediabetic State/diagnosis , Adult , Asian People , Cohort Studies , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/ethnology , Disease Progression , Female , Follow-Up Studies , Glucose Intolerance/blood , Glucose Intolerance/diagnosis , Glucose Intolerance/ethnology , Glucose Tolerance Test/methods , Humans , Japan , Male , Prediabetic State/ethnology , Predictive Value of Tests , Time Factors
5.
Diabet Med ; 31(5): 552-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24151911

ABSTRACT

AIMS: To investigate whether the elevation of liver enzymes is associated with the progression from normal to impaired glucose tolerance. METHODS: A historical cohort study was conducted in 594 male workers at public schools, who had normal glucose tolerance at baseline. The progression to impaired glucose tolerance and impaired fasting glycaemia during a mean follow-up of 3.1 years was measured using an oral glucose tolerance test. RESULTS: Overall, 141 (23.7%) subjects developed impaired glucose tolerance and 68 (11.4%) subjects developed impaired fasting glycaemia, 23 of whom had combined impaired fasting glycaemia/impaired glucose tolerance. The incidence of impaired glucose tolerance increased significantly with increasing quartiles of serum aspartate aminotransferase, alanine aminotransferase and γ-glutamyltransferase (P for trend <0.01). In Cox proportional hazards regression analysis, after adjusting for comprehensive risk factors, including plasma glucose levels, BMI and homeostatic model assessment of insulin resistance, the risk of progression to impaired glucose tolerance was significantly higher in the highest quartile of alanine aminotransferase than in the lowest quartile (hazard ratio 2.5; 95% CI 1.1-5.7). A significant association between alanine aminotransferase and the progression to impaired glucose tolerance was found after further adjustments for other liver enzymes or after the sample was limited to those with BMI < 25.0 kg/m(2) or with fasting plasma glucose < 5.5 mmol/l. CONCLUSIONS: A higher level of alanine aminotransferase was independently associated with progression from normal to impaired glucose tolerance in Japanese men. The elevation of alanine aminotransferase may be a change that occurs early in the evolution of diabetes.


Subject(s)
Glucose Intolerance/epidemiology , Hyperglycemia/epidemiology , Liver/enzymology , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Biomarkers/blood , Blood Glucose/metabolism , Body Mass Index , Cohort Studies , Disease Progression , Follow-Up Studies , Glucose Intolerance/metabolism , Glucose Tolerance Test , Humans , Hyperglycemia/metabolism , Japan/epidemiology , Male , Middle Aged , Prevalence , Risk Factors , gamma-Glutamyltransferase/blood
7.
Acta Diabetol ; 43(1): 34-5, 2006 May.
Article in English | MEDLINE | ID: mdl-16710648

ABSTRACT

Whereas the increase in insulin requirement in late gestation is well described in diabetic pregnancy, a decrease in insulin dosage in the end of the third trimester has also been noted in clinical experience and the prevention of hypoglycaemia is important. Here we report a large decrease (over 50%) in the final few weeks of her two gestations in a woman with type 1 diabetes mellitus.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Insulin/therapeutic use , Pregnancy Complications/drug therapy , Adolescent , Adult , Diabetes Mellitus, Type 1/physiopathology , Dose-Response Relationship, Drug , Female , Humans , Hypoglycemic Agents/therapeutic use , Pregnancy , Pregnancy Complications/physiopathology
8.
Proc Natl Acad Sci U S A ; 98(24): 13554-9, 2001 Nov 20.
Article in English | MEDLINE | ID: mdl-11698669

ABSTRACT

The deposition of amyloid beta-peptide (A beta) in the brain is closely associated with the development of Alzheimer's disease. A beta is generated from the amyloid precursor protein (APP) by sequential action of beta-secretase (BACE1) and gamma-secretase. Although BACE1 is distributed among various other tissues, its physiological substrates other than APP have yet to be identified. ST6Gal I is a sialyltransferase that produces a sialyl alpha 2,6galactose residue, and the enzyme is secreted out of the cell after proteolytic cleavage. We report here that BACE1 is involved in the proteolytic cleavage of ST6Gal I, on the basis of the following observations. ST6Gal I was colocalized with BACE1 in the Golgi apparatus by immunofluorescence microscopy, suggesting that BACE1 acts on ST6Gal I within the same intracellular compartment. When BACE1 was overexpressed with ST6Gal I in COS cells, the secretion of ST6Gal I markedly increased. When APP(SW) (Swedish familial Alzheimer's disease mutation), a preferable substrate for BACE1, was coexpressed with ST6Gal I in COS cells, the secretion of ST6Gal I significantly decreased, suggesting that that the beta-cleavage of overexpressed APP(SW) competes with ST6Gal I processing. In addition, BACE1-Fc (Fc, the hinge and constant region of IgG) chimera cleaved protein A-ST6Gal I fusion protein in vitro. Thus, we conclude that BACE1 is responsible for the cleavage and secretion of ST6Gal I.


Subject(s)
Aspartic Acid Endopeptidases/metabolism , Golgi Apparatus/metabolism , Sialyltransferases/metabolism , Alzheimer Disease , Amino Acid Sequence , Amyloid Precursor Protein Secretases , Amyloid beta-Protein Precursor/metabolism , Animals , Aspartic Acid Endopeptidases/genetics , COS Cells , Cell Line , Chlorocebus aethiops , Endopeptidases , Humans , Molecular Sequence Data , Mutagenesis , Sialyltransferases/genetics , Substrate Specificity , beta-D-Galactoside alpha 2-6-Sialyltransferase
9.
Eur J Cancer ; 37(9): 1158-65, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11378347

ABSTRACT

Differential displays of tumour/normal pair specimens of human oesophagus identified complement component 7 (C7) as being enhanced in normal tissues, but remarkably reduced in carcinoma tissues. In situ hybridisation confirmed the localisation of C7 mRNA in normal oesophageal epithelial cells and its disappearance in tumour cells. When mRNA expressions of other components were examined by means of semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in 10 tumour/normal pair specimens, significant reductions in C6 and C7 mRNAs were observed, while C3 and C5 mRNAs were enhanced in both normal and tumour tissues. A similar reduction was observed in colon and kidney cancers using the tumour/normal expression array analysis. Gene deletion of C7 was not found in the cell lines by Southern blot analysis. Our findings suggest a possible relationship between oesophageal tumorigenesis and reduced expression of C6 and C7 mRNAs, which is probably caused by a change in gene expression regulation and not by genetic loss of the locus.


Subject(s)
Complement C6/metabolism , Complement C7/metabolism , Esophageal Neoplasms/immunology , Animals , Blotting, Northern , Blotting, Southern , Blotting, Western , Male , RNA, Messenger/metabolism , Rats , Rats, Inbred WF , Reverse Transcriptase Polymerase Chain Reaction
10.
Jpn J Cancer Res ; 92(5): 506-15, 2001 May.
Article in English | MEDLINE | ID: mdl-11376559

ABSTRACT

Using the differential display method, latent transforming growth factor-beta 1 (TGF-beta 1) binding protein 1 (LTBP-1) mRNA was identified as one of the enriched mRNAs in ovarian carcinoma tissues after isolation of genes responsible for the development of ovarian cancer. Semi-quantitative reverse transcription (RT)-PCR analysis showed that expression of LTBP-1 and TGF-beta 1 mRNAs was much higher in both serous and mucinous adenocarcinomas than in their benign counterparts, including serous and mucinous cystadenomas and cystadenomas of low malignant potential (LMPs). Immunohistochemical analysis demonstrated that only proliferating benign adenoma cells were immunoreactive for both LTBP-1 and TGF-beta 1 proteins. In contrast, most serous and mucinous adenocarcinoma cells and their surrounding stroma were intensely immunoreactive for LTBP-1 and TGF-beta 1. LTBP-1 and TGF-beta 1 proteins, and their complex forms were identified in ovarian carcinoma cell lines and in their culture media by western blot analysis, suggesting these products were produced in ovarian carcinoma cells. RT-PCR analysis demonstrated that LTBP-1L, one of the LTBP-1 transcripts that has a strong activity in targeting the latent form of TGF-beta 1 to extracellular matrix (ECM), was predominantly expressed in ovarian carcinomas. Taken together, the results suggest that upregulation of LTBP-1 in ovarian carcinoma cells may have an important role in distributing TGF-beta1 in the stromal tissues surrounding carcinoma cells.


Subject(s)
Carrier Proteins/genetics , Gene Expression , Intracellular Signaling Peptides and Proteins , Ovarian Neoplasms/genetics , Transforming Growth Factor beta/genetics , Adenocarcinoma, Mucinous/chemistry , Adenocarcinoma, Mucinous/genetics , Blotting, Western , Carrier Proteins/analysis , Cystadenocarcinoma, Serous/chemistry , Cystadenocarcinoma, Serous/genetics , Cystadenoma, Mucinous/chemistry , Cystadenoma, Mucinous/genetics , Female , Humans , Immunohistochemistry , Latent TGF-beta Binding Proteins , Ovarian Neoplasms/chemistry , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Transforming Growth Factor beta/analysis
11.
Pharmacology ; 62(3): 157-62, 2001.
Article in English | MEDLINE | ID: mdl-11287817

ABSTRACT

Intraperitoneal injection of benzodiazepine receptor agonists (estazolam, zopiclone, triazolam: 0.03-0.24 mmol/kg) induces the head twitch response (HTR). The present study was undertaken to examine the possible participation of the serotonergic system in the mechanism of head twitches induced by benzodiazepine receptor agonists (BZ-RAs). The HTR induced by BZ-RAs was suppressed by pretreatment with ketanserine (1 mg/kg, i.p.), a selective 5-HT(2) receptor antagonist. Pretreatment with fluoxetine (10 mg/kg, i.p.), a 5-HT reuptake inhibitor, and 8-hydroxy-2-(di-n-propylamino)tetralin, a 5-HT(1A) receptor agonist, also suppressed the HTR induced by BZ-RAs. These results suggest that the HTR induced by BZ-RAs may be the result of an activation of postsynaptic 5-HT(2) receptors, probably due to direct action.


Subject(s)
Anti-Anxiety Agents/pharmacology , Behavior, Animal/drug effects , Estazolam/pharmacology , GABA-A Receptor Agonists , Piperazines/pharmacology , Triazolam/pharmacology , 8-Hydroxy-2-(di-n-propylamino)tetralin/pharmacology , Animals , Anti-Anxiety Agents/administration & dosage , Azabicyclo Compounds , Dihydroxytryptamines/pharmacology , Estazolam/administration & dosage , Fluoxetine/pharmacology , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/pharmacology , Ketanserin/pharmacology , Male , Mice , Piperazines/administration & dosage , Receptors, GABA-A/metabolism , Receptors, Serotonin/metabolism , Serotonin Antagonists/pharmacology , Serotonin Receptor Agonists/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Triazolam/administration & dosage
12.
Curr Atheroscler Rep ; 3(3): 252-9, 2001 May.
Article in English | MEDLINE | ID: mdl-11286647

ABSTRACT

In patients who have elevated levels of plasma ADMA, a relative deficiency of L-arginine has been found to contribute to the pathophysiology of athersclerosis, causing vasoconstriction, and accelerating atherogenesis. This finding--that there is a relative deficiency of L-arginine in atherosclerotic disease--is a breakthrough that will open new avenues of therapy.


Subject(s)
Arginine/deficiency , Arginine/analogs & derivatives , Arginine/antagonists & inhibitors , Arginine/blood , Enzyme Inhibitors/blood , Humans , Nitric Oxide/biosynthesis
13.
Am J Cardiol ; 85(3): 365-9, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-11078308

ABSTRACT

Patients with heart failure (HF) often have profound activity limitations and diminished quality of life (QOL) due to symptoms of dyspnea and fatigue. Although recent studies demonstrate positive physiologic and psychological benefits of low to moderate intensity, supervised, aerobic exercise training performed 3 to 5 days/ week for 20 to 40 minutes' duration, in a monitored setting, the efficacy of a home-based exercise program combining endurance and resistance exercise on symptoms and QOL, are unknown. This randomized controlled study examined the efficacy, safety, and adherence rates of a 3-month home-based combined walking and resistance exercise program on symptoms and QOL in 40 women and men aged 30 to 76 years with New York Heart Association class II to III HF. Baseline and 3-month evaluations consisted of a chronic HF questionnaire to assess symptoms and QOL and exercise capacity by symptom-limited treadmill exercise test with respiratory gas analysis. The exercise intervention improved fatigue (p = 0.02), emotional function (p = 0.01), and mastery (p = 0.04). Overall exercise adherence was excellent (90%) and there were no reported adverse events. A moderate intensity home-based combined walking and resistance program for patients with class II to III HF is safe and effective in reducing symptoms and improving QOL.


Subject(s)
Exercise Therapy , Exercise , Heart Failure/rehabilitation , Patient Compliance , Quality of Life , Walking , Adult , Aged , Female , Home Care Services, Hospital-Based , Humans , Male , Middle Aged , Surveys and Questionnaires , Treatment Outcome
15.
Brain Res ; 868(1): 141-6, 2000 Jun 16.
Article in English | MEDLINE | ID: mdl-10841899

ABSTRACT

Allylnitrile and crotononitrile induce behavioral abnormalities in mice. To explore the possible involvement of the vestibular system in these behavioral abnormalities, the expression of Fos protein, used as an indicator of neuronal activity, was examined within various brain structures in allylnitrile-, crotononitrile- and vehicle-treated mice. In each nitrile-treated mouse, Fos expression was observed in brain structures, which were divided into two groups. The structures in group 1 showed Fos expression between 1.5 h and 2 days postdosings, and in those in group 2 expression remained for up to 30 days postdosing. As most of these structures, especially in group 2, were identical to some Fos-positive structures observed after unilabyrinthectomy, the present results indicate that each nitrile induces Fos expression by causing a change in the peripheral vestibular system, resulting in behavioral abnormalities.


Subject(s)
Behavior, Animal/drug effects , Dyskinesia, Drug-Induced/physiopathology , Nitriles/pharmacology , Proto-Oncogene Proteins c-fos/physiology , Vestibular Nuclei/drug effects , Animals , Brain Chemistry/drug effects , Male , Mice , Vestibular Nuclei/physiology
16.
J Gerontol A Biol Sci Med Sci ; 55(2): M74-83, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10737689

ABSTRACT

BACKGROUND: Although inactivity is an important contributor to impaired functioning and disability with age, little is known concerning how improvements in physical functioning and well-being in older adults vary with the type of physical activity undertaken. METHODS: One hundred three adults age 65 years and older, recruited via population-based methods, were randomized to 12 months of community-based, moderate-intensity endurance and strengthening exercises (Fit & Firm) or stretching and flexibility exercises (Stretch & Flex). A combination of class- and home-based exercise formats was used. Measured and self-rated physical performance along with perceived functioning and well-being were assessed pre- and postintervention. RESULTS: Fit & Firm subjects showed greater 12-month improvements in both measured and self-rated endurance and strength compared to Stretch & Flex subjects. Stretch & Flex subjects reported greater improvements in bodily pain, and Stretch & Flex men evidenced greater improvements in flexibility relative to Fit & Firm subjects. Although overall exercise adherence was high in both exercise conditions (approximately 80%), subjects in both conditions showed better adherence to the home- versus class-based portions of their exercise prescriptions. CONCLUSIONS: Community-based programs focusing on moderate-intensity endurance and strengthening exercises or flexibility exercises can be delivered through a combination of formats that result in improvement in important functional and well-being outcomes. This represents one of the first studies to report significant improvements in an important quality of life outcome-bodily pain-with a regular regimen of stretching and flexibility exercises in a community-based sample of older adults.


Subject(s)
Activities of Daily Living , Attitude to Health , Exercise/physiology , Quality of Life , Aged , Analysis of Variance , Exercise/psychology , Female , Humans , Male , Multivariate Analysis , Muscle Contraction/physiology , Oxygen Consumption/physiology , Pain/prevention & control , Patient Compliance , Physical Endurance/physiology , Physical Fitness/physiology , Self Concept , Walking/physiology
17.
Prog Cardiovasc Nurs ; 14(3): 97-102, 1999.
Article in English | MEDLINE | ID: mdl-10549047

ABSTRACT

This study examined the relationship between perceived physical condition and measured physical fitness and activity levels in 40 patients with moderate heart failure (HF). Self rated physical condition, physical activity, self efficacy, and quality of life were evaluated by self administered questionnaires. Functional capacity was examined by cardiopulmonary exercise testing and 6 minute walk test. We found that physical activity levels were low. Participation in moderate intensity recreational activity and physical fitness were associated with self efficacy. Perceived physical condition was associated with emotional well being and levels of energy and fatigue. We conclude that self efficacy may reflect physical condition and physical activity levels in this sample of HF patients and may be a simple indicator of physical ability. Because of the association between perceived physical condition and emotional well being, caution must be taken when using self reports of physical condition. Further study is needed to explore these relationships.


Subject(s)
Heart Failure/psychology , Physical Fitness , Self Efficacy , Adult , Exercise Test , Female , Humans , Male , Middle Aged , Quality of Life , Self-Assessment , United States
18.
Arch Toxicol ; 73(1): 22-32, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10207611

ABSTRACT

A single dose of allylnitrile in mice might induce persistent behavioral abnormalities, of which the mechanism is not yet known. The present study was undertaken to explore the relationship between behavioral abnormalities and pathological changes in the brain of mice following exposure to allylnitrile. Exposure to allylnitrile (63, 84, and 112 mg/kg, p.o.) resulted in dose-dependent changes in behavioral abnormalities, including increased locomotor activity, circling, retropulsion, head twitching, and alteration in reflexive behavior, which appeared at day 2 postdosing and were persistent throughout the experimental period (60 days) at the higher dose levels. Allylnitrile produced neuronal retraction including hyperchromasia of the nuclei in the raphe nuclei, cerebral cortex, hypothalamus, hippocampal CA1 and dentate gyrus later than 30 days. No gliosis was observed in these regions. Not all but a significant number of neurons in the hippocampal CA1, medial habenula and raphe nuclei were immuno-reactive to CPP32 (Caspase-3) even at day 2. These neurons were also positive to Hoechst 33258 staining, indicating allylnitrile caused apoptotic changes in specific neurons when neuronal behaviors became apparent. These apoptotic changes were persistent even in the area without neuronal contraction such as medial habenula. However, almost all neurons in these areas were also positive to terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL). It is conceivable that allylnitrile caused apoptotic changes in neurons but did not always lead them to cell death immediately. Moreover, even when neuronal contraction resulted in retention of behavioral abnormalities, onset of these abnormalities seems to be associated with the impairment in the habenulo-raphe relay due to activation of apoptotic cascade in neurons.


Subject(s)
Apoptosis/drug effects , Behavior, Animal/drug effects , Brain/drug effects , Neurons/drug effects , Nitriles/adverse effects , Animals , Bisbenzimidazole , Brain/metabolism , Brain/pathology , Caspase 3 , Caspases/analysis , DNA Fragmentation/drug effects , Dose-Response Relationship, Drug , Dyskinesia, Drug-Induced/etiology , Histocytochemistry , Immunohistochemistry , In Situ Nick-End Labeling , Male , Mice , Motor Activity/drug effects , Neurons/metabolism , Neurons/pathology , Nitriles/administration & dosage , Time Factors
19.
J Biol Chem ; 273(13): 7375-81, 1998 Mar 27.
Article in English | MEDLINE | ID: mdl-9516434

ABSTRACT

Enzymatic elimination of heparan sulfate (HS) causes abnormal mesodermal and neural formation in Xenopus embryos, and HS plays an indispensable role in establishing the embryogenesis and tissue morphogenesis during early Xenopus development (Furuya, S., Sera, M., Tohno-oka, R., Sugahara, K., Shiokawa, K., and Hirabayashi, Y. (1995) Dev. Growth Differ. 37, 337-346). In this study, HS was purified from Xenopus embryos to investigate its disaccharide composition and binding ability to basic fibroblast growth factor (bFGF) and follistatin (FS), the latter being provided in two isoforms with core sequences of 315 and 288 amino acids (designated FS-315 and FS-288) originating from alternative mRNA splicing. Disaccharide composition analysis of the purified Xenopus HS showed the preponderance of a disulfated disaccharide unit with uronic acid 2-O-sulfate and glucosamine 2-N-sulfate, which has been implicated in the interactions with bFGF. Specific binding of the HS to bFGF and FS-288, the COOH-terminal truncated form, was observed in the filter binding assay, whereas HS did not bind to FS-315, indicating that the acidic Glu-rich domain of FS-315 precluded the binding. The binding of the HS to bFGF or FS-288 was markedly inhibited by heparin (HP) and various HS preparations, but not by chondroitin sulfate, supporting the binding specificity of HS. The binding specificity was further investigated using FS-288 and bovine intestinal [3H]HS. Competitive inhibition assays of the HS binding to FS-288 using size-defined HP oligosaccharides revealed that the minimum size required for significant inhibition was a dodecasaccharide, which is larger than the pentasaccharide required for bFGF binding. The binding affinity of FS to HS increased in the presence of activin, a growth/differentiation factor, which could be inactivated by direct binding to FS. These results, taken together, indicate that the structural requirement for binding of HS to bFGF and FS is different. HS may undergo dynamic changes in its structure during early Xenopus embryogenesis in response to the temporal and spatial expression of various growth/differentiation factors.


Subject(s)
Fibroblast Growth Factor 2/metabolism , Glycoproteins/metabolism , Growth Substances/metabolism , Heparitin Sulfate/metabolism , Xenopus/embryology , Activins , Animals , Cattle , Disaccharides/chemistry , Follistatin , Glycosaminoglycans/metabolism , Growth Substances/pharmacology , Heparitin Sulfate/chemistry , Inhibins/pharmacology , Protein Binding
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