Postpartal resumption of ovarian activity in dairy cows: Implications for herbage-based feeding systems in Switzerland.

INTRODUCTION: Milk production in Switzerland is mainly based on herbage feeding with little input of concentrates. The present study investigated the effects of a solely herbage-based diet with (C) and without concentrate (nC) supplementation on luteal activity, milk production and metabolic status in 23 multiparous Holstein dairy cows with early or delayed resumption of ovarian cyclicity post partum (pp). Cows were retrospectively assigned either to a group with early (until d 25 pp, EOV) or delayed resumption of ovarian activity (> d 30 pp, DOV), resulting in four subgroups depending on concentrate feeding: DOV-C, DOV-nC, EOV-C, EOV-nC. Milk progesterone (P4) concentration was measured every 3 d, and different metabolites were analyzed in weekly blood samples. Resumption of ovarian activity was detected between d 19 and 25 pp in EOV, and between d 30 and 60 pp in DOV. In DOV-C, resumption of cyclicity tended to start earlier (38.3 ± 1.7 d pp) compared to DOV-nC (45.2 ± 6.3 d pp; P = 0.10). Independent of grouping, the ovarian activity occurred later in cows with greater plasma ß-hydroxybutyrate (BHB) concentrations (P 1 ng/mL did not differ between groups (P > 0.05), but milk P4 peaks during the experiment were higher in EOV compared to DOV (P .

INTRODUCTION: En Suisse, la production laitière est principalement basée sur une alimentation à base d'herbe avec peu d'apport en concentrés. La présente étude a examiné les effets d'un régime alimentaire exclusivement à base d'herbe avec (C) et sans (nC) supplémentation de concentrés sur l'activité lutéale, la production laitière et le statut métabolique de 23 vaches laitières Holstein multipares ayant une reprise précoce ou retardée de la cyclicité ovarienne post-partum (pp). Les vaches ont été assignées rétrospectivement soit à un groupe avec une reprise précoce (jusqu'à 25 jours pp, EOV), soit retardée de l'activité ovarienne (> 30 jours pp, DOV), résultant en quatre sous-groupes en fonction de la supplémentation en concentrés: DOV-C, DOV-nC, EOV-C, EOV-nC. La concentration de progestérone (P4) dans le lait a été mesurée tous les 3 jours et différents métabolites ont été analysés dans des échantillons sanguins hebdomadaires. La reprise de l'activité ovarienne a été détectée entre le jour 19 et 25 pp en EOV et entre le jour 30 et 60 pp en DOV. En DOV-C, la reprise de la cyclicité avait tendance à commencer plus tôt (38,3 ± 1,7 jour pp) par rapport à DOV-nC (45,2 ± 6,3 jours pp; P = 0,10). Indépendamment du groupe, l'activité ovarienne est survenue plus tard chez les vaches avec des concentrations plasmatiques de ß-hydroxybutyrate (BHB) plus élevées (P 1ng/ml (P > 0,05), tandis que les pics de P4 dans le lait mesurés tout au long de l'expérience étaient plus élevés dans le groupe EOV par rapport au groupe DOV (P .

Polymorphism in promoter region of growth hormone receptor is associated with potential production capacity of insulin-like growth factor-1 in pre-pubertal Holstein heifers.

Insulin-like growth factor-1 (IGF-1) is one of the important factors for growth, milk production and reproductive functions and mainly released from the liver in response to growth hormone (GH) via GH receptor (GHR) in cattle. Recently, some single nucleotide polymorphisms (SNPs) were identified in the bovine GHR gene. Some GHR-SNPs were shown to be related to plasma IGF-1 concentration in cattle. Hence, the capacity to IGF-1 production in the liver might be affected by GHR-SNP and associated with performance in the future. This study examined whether GHR-SNP is associated with IGF-1 production in the liver of pre-pubertal heifers. In 71 Holstein calves, blood samples for genomic DNA extraction were obtained immediately after birth. To genotype the GHR-SNPs in the promoter region, polymerase chain reaction (PCR) products were digested with restriction enzyme NsiI (cutting sites: AA, AG and GG). All heifers at 4 months of age were intramuscularly injected with 0.4 mg oestradiol benzoate. Blood samples were obtained from the jugular vein just before (0 h) and 24 h after injection. The number of AA, AG and GG at the NsiI site was 0, 17 and 54 respectively. In AG and GG, plasma GH concentrations were higher pre-injection than 24 h post-injection (p < 0.01). Moreover, plasma GH concentrations in AG post-injection were higher than in GG (p < 0.05). In contrast, the GG genotype exhibited higher plasma IGF-1 concentrations in pre-injection than post-injection (p < 0.01), although oestradiol did not change IGF-1 concentration in the AG genotype. We conclude that the GG polymorphism in the promoter region of GHR is associated with a higher potential capacity of IGF-1 production in the liver of cattle.

Supplementation with difructose anhydride III promotes passive calcium absorption in the small intestine immediately after calving in dairy cows.

The incidence of hypocalcemia increases in high-parity dairy cows because resorption of bone Ca is delayed in these animals, and they appear to have a reduced ability to absorb Ca from the intestine during the early postpartum period. Difructose anhydride (DFA) III has been shown to promote the absorption of intestinal Ca via a paracellular pathway. However, past studies have not reported this effect in peripartum dairy cows. Therefore, we investigated the effect of DFA III supplementation on Ca metabolism during the peripartum period to determine whether DFA III promotes intestinal Ca absorption via this route. Seventy-four multiparous Holstein cows were separated into DFA and control groups based on their parity and body weight. The feed of the DFA group was supplemented with 40g/d of DFA III from -14 to 6d relative to calving. The control group did not receive DFA III. At calving (0h relative to calving), serum Ca declined below 9mg/dL in both groups. However, serum Ca concentrations were greater in the DFA group than in the control group at 6, 12, 24, and 48h relative to calving, and the time required for serum Ca to recover to 9mg/dL during the postpartum period was shorter in the high-parity cows in the DFA group than in those in the control group. Parathyroid hormone concentrations increased immediately after calving in both groups and were greater in the control group than in the DFA group at 12 and 24h relative to calving. Serum 1,25-dihydroxyvitamin D concentrations increased at 0 and 12h relative to calving in both groups and were higher in the control group than in the DFA group at 72h relative to calving. Serum concentrations of the bone-resorption marker cross-linked N-telopeptide of type I collagen (NTX) were not different between the groups during peripartum period, and serum NTX in all cows was lower at 0, 6, 12, 24, 48, and 72h relative to calving than at -21, 4, and 5d relative to calving. Thus, DFA treatment induced faster recovery of serum Ca, although bone resorption was restrained. In conclusion, DFA III promotes intestinal passive Ca absorption via the paracellular pathway during the early postpartum period; this absorption is unaffected by aging.

Effects of Dietary Contamination by Zearalenone and Its Metabolites on Serum Anti-Müllerian Hormone: Impact on the Reproductive Performance of Breeding Cows.

We investigated the effects of in vivo exposure to low zearalenone levels on the anti-Müllerian hormone endocrine levels and the reproductive performance of cattle. Urine and blood samples and reproductive records were collected from two Japanese Black breeding female cattle herds with dietary zearalenone contamination below the threshold levels (<1 ppm) at 30 days after calving. Urinary zearalenone, α-zearalenol and ß-zearalenol concentrations were measured by chromatography-tandem mass spectrometry, and serum anti-Müllerian hormone concentrations were determined along with serum biochemical parameters. Urinary concentrations of α-zearalenol were significantly higher (p < 0.05) in cattle in Herd 1 than in cattle in Herd 2, reflecting the different amounts of zearalenone in the diet of the two herds. Although the number of 5-mm and 10-mm follicles of the herds and their fertility after artificial insemination were similar, the serum anti-Müllerian hormone concentrations in herds 1 and 2 were 438.9 ± 48.6 pg/ml and 618.9 ± 80.0 pg/ml, respectively, with a trend towards a significant difference (p = 0.053), which may indicate differences in the antral follicle populations between herds. Thus, zearalenone intake from dietary feed, even when below the threshold zearalenone contamination level permitted in Japan, may affect the ovarian antral follicle populations, but not the fertility, of post-partum cows.

Short communication: Difructose anhydride III promotes calcium absorption from the duodenum in cattle.

Difructose anhydride (DFA) III promotes the intestinal absorption of calcium via a paracellular pathway in rats. In dairy cows, DFA III reaches the duodenum without being degraded by ruminal bacteria and hence could be used to control hypocalcemia. The aims of the present study were to investigate the percentage of DFA III that appears in the duodenum of cows and to determine the effect of DFA III on calcium absorption from duodenal fluid. The first experiment was performed in 3 ruminally and duodenally cannulated dry Holstein cows in a 3 × 3 Latin square design. Each experimental period lasted 7 d. On the first day, the cows were ruminally fed one of the following treatments: 0 (DFA0), 50 (DFA50), or 100 (DFA100) g/d of DFA III, using cobalt-EDTA as a liquid phase marker. Difructose anhydride III was detected in duodenal fluid 1 h after feeding, and its concentration peaked 4 h after feeding, in a dose-dependent manner. The percentages of DFA III that appeared in the duodenum after the DFA50 and DFA100 treatments were 69.1 ± 7.0% and 67.9 ± 5.6%, respectively. The second experiment used the everted duodenal sacs of cattle (n = 7 in each group). Sacs were incubated in artificial mucosal fluid containing 1 mM DFA III or no DFA III (control) for 60 min with 100% O2 in a water bath at 37 °C. After incubation, the calcium concentration of the artificial serosal fluid in the everted sacs was measured. Calcium absorption was higher in the DFA III-treated group than in the control group (803 ± 161 and 456 ± 74 nmol/cm of sac, respectively). The above results demonstrate that approximately 70% of administered DFA III reached the duodenum of cows intact. Moreover, similar to its effects on calcium absorption in rats, DFA III promoted calcium absorption via a paracellular pathway in the duodenum of cows.

Superconductivity at 52 K in hydrogen-substituted LaFeAsO(1-x)Hx under high pressure.

The 1111-type iron-based superconductor LnFeAsO(1-x)Fx (Ln stands for lanthanide) is the first material with a Tc above 50 K, other than cuprate superconductors. Electron doping into LaFeAsO by H, rather than F, revealed a double-dome-shaped Tc-x diagram, with a first dome (SC1, 0.0550 K observed in RE-1111 compounds (RE: Pr, Sm, and Gd) at ambient pressure is the merging of SC1 and SC2.

Metabolic and energy status during the dry period is crucial for the resumption of ovarian activity postpartum in dairy cows.

It is well known that the degree of negative energy balance in high-producing dairy cows is the major cause of delayed resumption of the ovarian cyclicity that closely relates to fertility. Recent evidence suggests that the energetic situation during early lactation critically affects nutrient partitioning, metabolism, and the reproductive axis, whereas the effect of energy status during the dry period is widely unknown. The aim of the present study was to investigate the effect of energy status throughout the entire dry period until early lactation on the onset of the ovarian cyclicity. Blood samples were taken in 23 cows from dry off at 8 wk before expected parturition to 8 wk postpartum for the analyses of metabolites and hormones, and milk samples were obtained 3 times weekly from d 7 of lactation onward to confirm luteal activity and pregnancy by milk progesterone analysis. Energy balance (EB) was measured weekly during the last 6 wk of the dry period and every other week after parturition. Liver biopsies were obtained at 8 wk before expected calving, within 1 d after calving, and at 4 wk postpartum to measure the mRNA abundance of various gluconeogenic enzymes and metabolic hormone receptors. Cows showing luteal activity within 3 wk postpartum were defined as ovulatory during the first follicular wave postpartum (OC), whereas cows without luteal activity within 3 wk postpartum were defined as anovulatory (AC). Energy balance and, concomitantly, plasma concentrations of glucose, insulin, insulin-like growth factor-1, 3,5,3'-triiodothyronine, and thyroxine were higher in OC than in AC during the dry period. Plasma thyroxine concentrations and body condition score during the postpartum period were higher in OC than in AC. At the mRNA level (19 cows), hepatic insulin receptor decreased from dry off to early lactation, and mRNA of pyruvate carboxylase was highest at parturition and decreased in early lactation in AC only, whereas both parameters remained unchanged in OC. The mRNA abundance of phosphoenolpyruvate carboxykinase-mitochondrial increased from dry off to parturition in both groups, remained high in OC, and decreased again in early lactation in AC. However, none of the investigated gene transcripts differed between OC and AC cows. Thus, ovarian function postpartum appears to be crucially influenced by the energy status during the dry period, which is reflected by timely changes in hepatic mRNA abundance of only a few key metabolic factors in the liver.

Oestradiol enhances plasma growth hormone and insulin-like growth factor-I concentrations and increased the expression of their receptors mRNAs in the liver of ovariectomized cows.

Many metabolic hormones, growth hormone (GH), insulin-like growth factor-I (IGF-I) and insulin affect ovarian functions. However, whether ovarian steroid hormones affect metabolic hormones in cattle remains unknown. This study aimed to determine the effect of sex steroids on the plasma profiles of GH, IGF-I and insulin and their receptors in the liver and adipose tissues of dairy cows. Ovariectomized cows (n = 14) were randomly divided into four groups: control group (n = 3) was treated with saline on Day 0; oestradiol (E2) group (n = 3), with saline and 1 mg oestradiol benzoate (EB) on Day 0 and 5, respectively; progesterone (P4) group (n = 4) with two CIDRs (Pfizer Inc., Tokyo, Japan) from Day 0; and E2 + P4 group (n = 4) with two CIDRs on Day 0 that were removed on Day 6 and were immediately injected with 1 mg EB. The animals were euthanized after the experiment, and liver and adipose tissues samples were quantitatively analysed using real-time PCR for the expression of mRNA for the GH (GHR), IGF-I (IGFR-I) and insulin (IR) receptor mRNAs. Oestradiol benzoate significantly increased the number of peaks (p < 0.05), pulse amplitude (p < 0.05) and area under the curve (AUC; p < 0.01) for plasma GH; moreover, it increased plasma IGF-I concentration (p < 0.05), but it had no effect on the plasma insulin profile. P4 significantly decreased the AUC (p < 0.01), compared with the control group, whereas it did not affect the number of peaks and the amplitude of GH pulses. P4 + E2 did not affect the GH pulse profile. E2 increased the mRNA expression of GHR, IGFR-I and IR in the liver (p < 0.05), whereas both P4 and E2 + P4 did not change their expressions. Our results provide evidence that the metabolic and reproductive endocrine axes may regulate each other to ensure optimal reproductive and metabolic function.

Effect of ß-carotene supply during close-up dry period on the onset of first postpartum luteal activity in dairy cows.

The aim of this study was to examine the effect of ß-carotene supply during the close-up dry period on the onset of first postpartum luteal activity in dairy cows. Twelve cows were supplied with 2000 mg of ß-carotene (20 g Rovimix(®) ß-Carotene containing 10% ß-carotene; DSM Nutrition Japan K.K., Tokyo, Japan) by oral administration daily from day 21 before expected calving date to parturition. Fourteen cows (control) did not receive ß-carotene supplementation. Blood samples were obtained on days 21, 14 and 7 before expected calving date and on days 1, 7, 14, 21 postpartum. When the plasma progesterone concentration exceeded 1 ng/ml by day 21 postpartum, luteal activity was assumed to have been initiated. The result showed that serum ß-carotene concentrations in the ß-carotene cows were higher than in the control cows during the experimental period (p < 0.01). The number of cows with the onset of luteal activity by day 21 postpartum was 9/12 in the ß-carotene cows and 4/14 in the control cows (p < 0.05). Retinol, certain metabolic parameters and metabolic hormones concentrations did not differ between ß-carotene and control cows. In addition, serum retinol concentration in ß-carotene cows without luteal activity was lower than in ß-carotene cows with luteal activity (p < 0.05), and serum gamma-glutamyl transpeptidase concentration in ß-carotene cows with luteal activity (p < 0.05) and control cows without luteal activity (p < 0.01) was higher than in control cows with luteal activity. In conclusion, ß-carotene supply during the close-up dry period may support the onset of luteal activity during early lactation in dairy cows.

Relationship between plasma beta-carotene concentrations during the peripartum period and ovulation in the first follicular wave postpartum in dairy cows.

Beta-carotene functions independently of vitamin A in the reproductive performance of dairy cows. The concentrations of beta-carotene in plasma decrease during the dry period, and reach a nadir in about the first week postpartum. This coincides with a negative energy balance, which affects the onset of the first ovulation in early postpartum cows. Thus, we hypothesised that plasma beta-carotene concentrations during the peripartum period may affect ovulation in the first follicular wave postpartum in dairy cows. The aim of the present study was to investigate changes in the profiles of plasma beta-carotene concentrations during the peripartum period in ovulatory and anovulatory cows during the first follicular wave postpartum. We used 22 multiparous Holstein cows, which were fed a total mixed ration consisting of grass, corn silage and concentrate, and collected blood samples for beta-carotene and progesterone analysis from week 3 prepartum to week 3 postpartum when the period of day 0-6 after parturition was regarded as the parturient week (week 0). The first ovulation was confirmed using the profile of plasma progesterone concentrations and colour Doppler ultrasound. Thirteen cows ovulated during the first postpartum follicular wave. Parity, the dry-off period, calving interval, mastitis episodes, and actual 305 days' milk yield during the previous lactation, and milk composition in the last month during the previous lactation in this study did not differ between ovulatory and anovulatory cows. Differences in the plasma beta-carotene profile were observed between ovulatory and anovulatory cows. Plasma beta-carotene concentrations at week 3 prepartum were greater in ovulatory cows (2.97+/-0.24 mg/L) than in anovulatory cows (1.53+/-0.14 mg/L; P<0.001), after that its concentrations in ovulatory cows decreased and reached the lowest level at week 1 postpartum, although its concentrations in anovulatory cows remained unchanged. No differences in plasma beta-carotene concentrations between the two groups were observed postpartum. The present study indicates for the first time that the lower beta-carotene concentrations in plasma during the prepartum period is associated with anovulation during the first follicular wave postpartum.

Peripheral administration of kisspeptin-10 increases plasma concentrations of GH as well as LH in prepubertal Holstein heifers.

This study was conducted to estimate the effects of kisspeptin-10 on blood concentrations of LH and GH in prepubertal dairy heifers. Heifers received a single injection of 1 mg kisspeptin-10 (n=5) or saline (n=5) intravenously, and serial blood samples were collected at 15-min intervals to analyze the response curves of both LH and GH after injection. Peak-shaped responses were observed for concentrations of LH and GH, and the peaks were observed at 27+/-3 and 75+/-9 min, respectively, after injection, only in heifers injected with kisspeptin-10. These data suggest various possible important links among kisspeptin, the reproductive axis, and also the somatotropic axis in prepubertal Holstein heifers.

Short communication: A positive relationship between the first ovulation postpartum and the increasing ratio of milk yield in the first part of lactation in dairy cows.

The aim of the present study was to examine the relationship between characteristics of the lactation curve, on the basis of daily milk yield, and ovulation within 3 wk postpartum as an indicator of early return to luteal activity in dairy cows. Lactation records from 46 lactating Holstein cows between calving and 305 d postpartum were studied. Milk samples were collected twice weekly between d 7 and 100 for later determination of progesterone concentrations. Occurrence of an early first ovulation was determined by an increase in milk progesterone by 3 wk after calving. Milk yield was recorded daily until 305 d postpartum, and average yield was calculated weekly. The lactation curve was characterized by 8 indices on the basis of the weekly average of milk yield as follows: a) first-week milk yield; b) peak milk yield; c) actual 305-d milk yield; d) peak week; e) difference in milk yield between the first week and peak week; f) difference in milk yield between the peak week and last week (43rd week postpartum); g) ratio of increase in milk yield between wk 1 and the week of peak yield; and h) ratio of decline in milk yield between the week of peak yield and the last week. Indices g and h were calculated as linear. The number of cows having ovulated by 3 wk postpartum was 22 (47.8%). The resumption of ovarian cycles with normal luteal phases occurred earlier in ovular cows than in anovular cows (32.0 d vs. 57.1 d). Although total milk yield did not differ between ovular and anovular cows, the ratio of increase in milk yield from the first week to the peak week (index g) in ovular cows was smaller compared with that of anovular cows (1.71 vs. 2.54). In addition, the ratio of increase in milk yield from the first week to the third week postpartum was greater in anovular cows by 3 wk postpartum (ovular = 1.43 +/- 0.23 vs. anovular = 2.32 +/- 0.29). In conclusion, the present study demonstrates that a greater increasing ratio of milk yield during early lactation may delay resumption of ovarian cycles after parturition. Therefore, this study is the first to demonstrate statistically that a smaller increasing ratio of milk yield (index g) during early lactation may have a beneficial effect on the first ovulation by 3 wk postpartum.

Insulin-like growth factor-I (IGF-I) system during follicle development in the bovine ovary: relationship among IGF-I, type 1 IGF receptor (IGFR-1) and pregnancy-associated plasma protein-A (PAPP-A).

Insulin-like growth factor-I (IGF-I) system that is exerted mainly through the type 1 IGF receptor (IGFR-1) and releasing of free IGF-I is regulated by the proteases of IGF-binding proteins (IGFBPs), an important factor in follicle development of bovine ovary. The aims of the present study were to examine the mRNA expressions of IGF-I, IGFR-1 and pregnancy-associated plasma protein-A (PAPP-A) in granulosa cells and theca tissues during bovine follicular development and the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of these genes in cultured bovine granulosa cells. Follicles were classified into four groups such as small follicle (SF), estrogen inactive dominant follicle (EID), estrogen active dominant follicle (EAD) and preovulatory follicle (POF). The concentration of free IGF-I in follicular fluid of POF was significantly higher than those in EID, whereas the total IGF-I in follicular fluid did not change at all developmental stages. The expression of IGF-I mRNA was not detected in the granulosa cells at all at any developmental stages but the expression was detected in the theca tissues. The amount of IGFR-1 mRNA in granulosa cell showed the constant level at all developmental stages except EID. The expressions of IGFR-1 and PAPP-A in cultured bovine granulosa cells were stimulated with FSH but not with E2. The PAPP-A mRNA expression was stimulated by FSH in presence of 1 ng/ml E2. These results indicate that IGF-I in follicular fluid is mainly derived from the circulation and that FSH is an inducer for the expression of IGFR-1 and PAPP-A genes in granulosa cells. Therefore, we suggest that PAPP-A stimulated with FSH play a crucial role for IGF-I system in bovine follicular development.

In silico assessment of gene function involved in cysteine biosynthesis in Arabidopsis: expression analysis of multiple isoforms of serine acetyltransferase.

In plants, the inorganic sulfur is first fixed into cysteine by the cysteine biosynthetic pathway. This biosynthetic pathway of cysteine involves several enzymatic reactions. In Arabidopsis thaliana, multiple isoforms seem to participate in each enzymatic step for cysteine biosynthesis. To obtain more insights on the specific role of each isoform involved in the cysteine biosynthesis, in silico analysis of these isoforms using Arabidopsis expressed sequence tags (EST) database was carried out. This EST database analysis revealed distinct population distribution of ESTs among multiple isoforms, suggesting that each isoform has its particular expression pattern, presumably associated with its specific role in cysteine biosynthesis. As another in silico analysis, co-expression analysis of genes involved in sulfur metabolism in Arabidopsis was performed using a public transcriptome database of DNA microarrays. This co-expression analysis also suggested specific function and co-regulation of some isoform genes for cysteine biosynthesis by consideration on the clustering of co-expressed genes. From the results of sensitivity to feedback regulation, subcellular localization and expression of mRNA analyses, each serine acetyltransferase (SATase) isoform seems to have its specific role for cysteine biosynthesis. Similar expression patterns were observed between the experimental results of expression data for SATase isoforms and the in silico results of "digital northern" analysis using EST database.

Delivery of immunoprophylactics in transgenic plants: current status.

The search for economic alternatives for the production of recombinant immunoprophylactics has resulted in the concept of generating them in plants at relatively low cost. Two basic strategies are employed: the expression of recombinant antigens or antibodies in transgenic plants, or the presentation of small antigen epitopes on the surface of genetically modified plant viruses. Both approaches have resulted in the production of biologically active immunoprophylactics that have been shown in animal studies to protect from the development of disease symptoms. An especially interesting feature of producing vaccines in edible plant parts is the potential to use the transgenic plant as a vehicle for oral delivery. Substantial progress has been made over the past few years, and the first clinical trials have demonstrated the potential of this new technology. Future challenges are to express the immunoprophylactics at controlled, high concentrations in plants that could be grown locally where they are needed, and to develop easy and standardised administration procedures.

[Analysis of the state of patients with rheumatoid arthritis using a personal computer].

The present study was designed to analyze the state of 203 patients with rheumatoid arthritis (RA) in our clinic using a personal computer. The duration of the disease was significantly correlated with the progression of radiographical stages of RA, indicating that no drugs were able to prevent the progression of joint destruction. Nevertheless, bucillamine, a newly developed anti-rheumatic drug, was found to be effective in some patients who did not respond to D-penicillamine, but not vice versa. Although seropositive RA patients had more severe disease than seronegative RA patients, serum rheumatoid factor levels were not significantly correlated with Lansbury indices in seropositive RA patients. Overall, either the liver function or the renal function was not significantly affected in any category of the patients. Taken together, it is suggested that analysis of the data of the RA patients with personal computer systems provide useful information on the management of the RA patients.

Angina pectoris caused by dynamic exercise in hypertrophic cardiomyopathy with normal coronary arteries.

To evaluate the relationship between angina pectoris caused by dynamic exercise and the time course of heart rate (HR) and hemodynamics during dynamic exercise in 15 patients with hypertrophic cardiomyopathy (HCM) with normal epicardial coronary arteries, the supine ergometer exercise test was performed during cardiac catheterization. The HCM patients were divided into a chest pain group (n = 6) and a no chest pain group (n = 9) based upon the results of the ergometer exercise test. There was no significant difference in the level of ST-segment depression after exercise in both the chest pain and no chest pain groups (-2.1 +/- 0.6 mm vs -2.6 +/- 1.1 mm, NS). Increase in heart rate (HR) and left ventricular end-diastolic pressure (LVEDP) in the early phase of the exercise test was significantly greater in the chest pain group compared with the no chest pain group. These observations suggest that in HCM patients, the occurrence of exertional chest pain has a close relationship with the rapid increase in HR and LVEDP in the early phase of dynamic exercise, but does not have a relationship with the gradual increase in these parameters.

Characterization of a glucuronyltransferase: neolactotetraosylceramide glucuronyltransferase from rat brain.

The properties of a rat brain glucuronyltransferase, which is presumed to be associated with the biosynthesis of the HNK-1 epitope on sulfoglucuronyl glycolipids, are described. The enzyme required divalent cations for reaction, with maximal activity at 10 mM Mn2+, and exhibited a dual optimum at pH 4-5 and pH 6 depending upon the buffer used, with the highest activity at pH 4.5 in MES buffer. This enzyme strictly recognized the Gal beta 1-4GlcNAc terminal structure, and was highly specific for neolacto (type 2) glycolipids as acceptor. The enzyme was localized specifically in the brain, and was barely detected in other issues, including the thymus, spleen, liver, kidney, lung, and sciatic nerve fibres. Phosphatidylinositol and phosphatidylserine increased the enzymatic reaction 4.4- and 2.3-fold, respectively, whereas phosphatidylcholine slightly decreased the rate.

A novel glucuronyltransferase in nervous system presumably associated with the biosynthesis of HNK-1 carbohydrate epitope on glycoproteins.

Recently, embryonic chicken brain extract was shown to contain a glucuronyltransferase, which transfers glucuronic acid from UDP-glucuronic acid to glycolipid acceptors (neolactotetraosyl ceramide). The enzyme was also suggested to transfer glucuronic acid to glycoprotein acceptors (asialoorosomucoid) (Das, K. K., Basu, M., Basu, S., Chou, D. K. H., and Jungalwala, F. B. (1991) J. Biol. Chem. 266, 5238-5243). In this study, the glucuronyltransferase activity in rat brain extract was separated into two groups by UDP-glucuronic acid-Sepharose CL-6B column chromatography. The enzyme recovered predominantly in the effluent fraction (GlcAT-L) catalyzed the transfer of glucuronic acid to glycolipid acceptors but not to glycoprotein acceptors, whereas the enzyme recovered in the eluate fraction (GlcAT-P) transferred glucuronic acid most predominantly to glycoprotein acceptors and very little to glycolipid acceptors. GlcAT-P was able to transfer glucuronic acid to oligosaccharide chains on asialoorosomucoid. The enzyme recognized a terminal lactosamine structure, Gal beta 1-4GlcNAc, on glycoproteins. It was localized in the nervous system and was hardly detectable in other tissues, including the thymus, spleen, lung, kidney, and liver. Although GlcAT-L and GlcAT-P shared some properties in common such as tissue distributions and developmental changes, they exhibited marked differences in their phospholipid dependence and in their pH profiles, apart from their respective acceptor preference to glycolipids and glycoproteins. The acceptor specificity and tissue distribution suggest that a novel glucuronyltransferase, GlcAT-P, is involved in the biosynthesis of the sulfoglucuronylgalactose structure in the HNK-1 carbohydrate epitope that is expressed on glycoproteins.