Biomedical subjects

S Kume

Publications and source records attributed to S Kume.

At least 55 records · Page 3Linked to original sources

PubMed1996

Intracellular levels of cyclic AMP and cyclic GMP differentially modify platelet aggregate size in human platelets activated with epinephrine or ADP.

We investigated the effects on human platelet aggregation of several agents that increase either intracellular cyclic AMP or cyclic GMP, using a platelet aggregometer that allows quantification of the size and number of platelet aggregates. During the initial phase of aggregation induced by epinephrine and ADP, small aggregates consisting of < 100 cells predominated; large aggregates formed later. Prostaglandin I2 (PGI2), which increases intracellular cyclic AMP, suppressed the formation of small as well as large aggregates induced by epinephrine, with ID50 values of 10.7 +/- 2.8 and 3.8 +/- 0.5 nM, respectively. ADP-induced formation of small and large aggregates was also inhibited by PGI2, with similar ID50 values. Dibutyryl cyclic AMP (db cyclic AMP), a cell-permeant form of cyclic AMP, also inhibited small and large aggregate formation induced by epinephrine or ADP, with ID50 values of 420-560 microM for small aggregates and 139-166 microM for large aggregates, respectively. On the other hand, nitroprusside, which increases intracellular cyclic GMP, inhibited only the formation of large aggregates, with an ID50 value of 454 +/- 191 nM for epinephrine-induced activation and of 2.1 +/- 0.6 microM for ADP-induced activation. Nitroprusside at 1 mM did not affect the formation of small aggregates induced by epinephrine, whereas that of large aggregates was completely blocked at 10 microM. 8-Bromo cyclic GMP (8-br cyclic GMP) also inhibited only the formation of large aggregates, with ID50 values of 140-170 microM, but not that of small aggregates induced by epinephrine and ADP. Milrinone, which increases the intracellular level of both cyclic AMP and cyclic GMP, suppressed the formation of small and large aggregates induced by epinephrine and ADP. These findings suggest that cyclic AMP and cyclic GMP differentially modify the size of aggregates formed during epinephrine or ADP activation.

Adenosine Diphosphate↗

PubMed1996

Effect of supplemental lactoferrin with ferrous iron on iron status of newborn calves.

Data for 18 male and 18 female calves, born from primiparous and multiparous cows, were collected to determine the effect of supplemental lactoferrin and FeSO4 for 5 d after parturition on the Fe status of calves. Dietary treatments were 1) untreated, 2) 40 mg of Fe/d as FeSO4, and 3) 40 mg of Fe as FeSO4 plus 5 g of lactoferrin/d. Blood hematocrit and hemoglobin of calves born from primiparous cows at d 1 of age were lower than those of calves born from multiparous cows, but not different from those of their dams. Blood hematocrit and hemoglobin of male calves at d 1 of age were lower than those of female calves. Plasma Fe of primiparous cows at parturition was lower than that of multiparous cows, but plasma Fe of calves was not affected by parity of dam and sex of calf. Blood hematocrit and hemoglobin of untreated calves decreased from 1 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe of Fe plus lactoferrin increased from 2 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe plus lactoferrin were higher than those of calves treated with Fe at d 6 of age. Plasma Fe of calves treated with Fe or Fe plus lactoferrin increased temporarily at d 2 of age. Plasma Fe of calves treated with Fe plus lactoferrin at d 2 of age was lower than that of calves treated with Fe, but, at d 6 and 10 of age, plasma Fe of calves treated with Fe plus lactoferrin were higher.

Animals↗

PubMed1996

Protein-tyrosine phosphorylation and p72syk activation in human platelets stimulated with collagen is dependent upon glycoprotein Ia/IIa and actin polymerization.

In human platelets treated with acetylsalicylic acid, collagen induced protein-tyrosine-phosphorylation of several proteins. The major 75 kDa band included cortactin and auto-phosphorylated p72syk. p72syk activity rapidly increased upon collagen stimulation, whereas p60c-src activation was below detectable levels. A combination of inhibitors to remove the effects of extracellular and intracellular Ca2+, released ADP, and fibrinogen binding to GPIIb/IIIa delayed and attenuated the major 75 kDa band. By contrast, p72syk activation was not inhibited by these treatments. Cytochalasin D completely inhibited protein tyrosine phosphorylation and p72syk activation. It also potently inhibited aggregation and [Ca2+]i elevation. Anti-GPIa/IIa MoAb in a concentration-dependent manner partially attenuated protein tyrosine phosphorylation and p72syk activation. Its inhibitory effects on intracellular Ca2+ mobilization, release of intracellular granule contents, and aggregation also were partial. No tyrosine kinase activity was coprecipitated with GPIa/IIa. These results suggest that p72syk activation lies upstream of protein tyrosine phosphorylation, Ca2+ mobilization, ADP release, thromboxane A2 production and aggregation. GPIa/IIa plays a key role in p72syk activation induced by collagen, but other collagen receptors may work in synergy to fully activate p72syk. Actin polymerization is a prerequisite for both p72syk activation and other intracellular signal transduction pathways.

Actins↗

PubMed1995

Fc gamma II receptor-mediated platelet activation induced by anti-CD9 monoclonal antibody opens Ca2+ channels which are distinct from those associated with Ca2+ store depletion.

Anti-human platelet CD9 mAb, NNKY1-19, induced platelet activation in a Fc gamma RII-dependent manner in terms of aggregation and secretion of intracellular granule contents. These responses were considerably suppressed by aspirin. [Ca2+]i elevation in the absence of extracellular Ca2+ ([Ca2+]e), which represents the amount of Ca2+ released from intracellular Ca2+ ([Ca2+]i) stores, was also greatly reduced, whereas Ca2+ influx was sustained at similar levels. We thus investigated the mechanism that leads to the opening of Ca2+ channels in platelets incubated with aspirin. IP3 production and Ca2+ efflux were below detectable levels. 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid loading of platelets to chelate [Ca2+]i did not reduce Ca2+ influx, as assessed by 45Ca2+ measurement. These findings suggested that NNKY1-19 induces Ca2+ channels to open without [Ca2+]i mobilization or by depleting the [Ca2+]i stores. The magnitude of Ca2+ influx was evaluated by adding [Ca2+]e to a platelet suspension activated by various agonists in the absence of [Ca2+]e. The dose dependence of the Ca2+ influx on [Ca2+]e concentrations differed according to the mode of activation. The ED50 value of Ca2+ after thrombin or thapsigargin stimulation was 0.6 mM, whereas that of NNKY1-19 activation was about 3 mM. The addition of anti-Fc gamma RII mAb, IV.3, even 10 min after the initiation of platelet activation induced by NNKY1-19, inhibited the Ca2+ influx. These findings suggest that the Fc gamma RII-dependent activation of platelets induced by NNKY1-19 directly opens Ca2+ channels, which are distinct from those opened by thrombin or thapsigargin.

Antibodies, Monoclonal↗

PubMed1995

Sulphonylurea agents inhibit platelet aggregation and [Ca2+]i elevation induced by arachidonic acid.

The effects of three hypoglycaemic agents--glimepiride, glibenclamide and gliclazide--were evaluated on platelet aggregation and intracellular Ca2+ elevation induced by arachidonic acid. Platelet aggregation was assessed both by the conventional method using changes in light transmission and by a newly-developed procedure using light scattering which allows the detection of small as well as large aggregates. Glimepiride and glibenclamide inhibited the formation of small and large aggregates induced by optimal concentrations of arachidonic acid in a dose-dependent manner. The ID50 values for the inhibition of platelet aggregation were approximately one third of those for arachidonic acid metabolism, suggesting that both agents have certain direct inhibitory effects on platelet aggregation unrelated to arachidonic acid metabolism. Gliclazide inhibited the formation of small aggregates induced by low concentrations of arachidonic acid to a limited extent. However, it inhibited the formation of large aggregates but not small aggregates when higher concentrations of arachidonic acid were used. Glimepiride and glibenclamide inhibited [Ca2+]i elevation induced by arachidonic acid in a dose-dependent manner, whereas gliclazide had no inhibitory effect. Taken together, these suggest that gliclazide does not inhibit arachidonic acid metabolism but does have certain direct inhibitory effects on platelet aggregation.

Arachidonic Acid↗

PubMed1995

Protein tyrosine phosphorylation in human platelets induced by interaction between glycoprotein Ib and von Willebrand factor.

The interaction between von Willebrand factor (vWF) and glycoprotein Ib (GPIb) induced by ristocetin or botrocetin resulted in associated platelet aggregation, protein tyrosine phosphorylation (PTP) of a 64 kDa protein, as detected by a monoclonal antibody against phosphotyrosine (PY-20), and intracellular Ca2+ elevation that is largely dependent upon Ca2+ influx in human platelets. It is of interest that 75-80, 97 and 125 kDa proteins which are strongly tyrosine-phosphorylated in platelet activation induced by thrombin and other agonists were not detected. Neither vWF nor a coaggregating agent (ristocetin or botrocetin) alone induced aggregation, [Ca2+]i elevation or the 64 kDa PTP. NMC-4, an antibody which inhibits both ristocetin- or botrocetin-induced vWF binding to GPIb, abolished the appearance of the 64 kDa PTP as well as other responses, suggesting that it is specifically induced by the GPIb-vWF interaction. Aspirin, or ONO-3708, a competitive inhibitor of thromboxane A2, did not modify the 64 kDa PTP, while [Ca2+]i elevation was moderately suppressed. Depletion of extracellular Ca2+ or RGD peptides suppressed neither the 64 kDa PTP nor aggregation. H-7, a protein kinase C inhibitor, did not inhibit the 64 kDa PTP, while staurosporine, a potent protein kinase inhibitor, inhibited the 64 kDa PTP and Ca2+ influx, but not aggregation, in a dose-dependent manner. It is suggested that the 64 kDa PTP is associated with platelet aggregation induced by the interaction between GPIb and vWF.

Alkaloids↗

PubMed1995

Gq pathway desensitizes chemotactic receptor-induced calcium signaling via inositol trisphosphate receptor down-regulation.

Desensitization of a chemotactic receptor is an adaptive process that terminates inflammation. Although homologous desensitization can be well explained by the action of specific receptor kinases, the mechanisms of heterologous desensitization remain elusive. As an approach to evaluate the roles of Gq pathway in desensitization of calcium signaling, we expressed a constitutively active Gq alpha mutant (Gq alpha Q-L) together with platelet-activating factor (PAF) receptor in Xenopus laevis oocytes. Gq alpha Q-L expression completely attenuated the calcium-sensitive chloride current and the 45Ca release elicited by PAF. The Gq-mediated desensitization could not be ascribed to G protein/receptor uncoupling via receptor phosphorylation, because (i) PAF-induced inositol 1,4,5-trisphosphate (IP3) synthesis was only partially suppressed and (ii) a mutated PAF receptor devoid of all Ser and Thr in the third cytoplasmic loop and in the C-terminal tail was also completely desensitized by Gq alpha Q-L. In Gq alpha Q-L expressing oocytes, microinjection of IP3 failed to elicit the calcium response, and the IP3 receptor, detected by a specific antibody, disappeared. Thus, the Gq-mediated desensitization can be most likely explained by IP3 receptor down-regulation. These novel mechanisms may explain in part heterologous desensitization in chemotactic factor-stimulated inflammatory cells.

Animals↗

PubMed1995

Localization of advanced glycation end products of Maillard reaction in bovine tissues and their endocytosis by macrophage scavenger receptors.

In aged bovines, the accumulation of advanced glycation end-products (AGEs) in macrophages, endothelial cells, adventitial cells, or pericytes; epithelial or parenchymal cells of some organs such as the liver, adrenals, and kidneys; neuronal cells in the brain; and extracellular matrix was demonstrated by immunohistochemistry using anti-AGE monoclonal antibody 6D12. Immunoelectron microscopy demonstrated the localization of AGEs in the endosomal and lysosomal compartments of various types of cell and in the extracellular matrix. By biochemical characterization of the interaction of AGEs with bovine alveolar macrophages using [125I]AGE-bovine serum albumin (BSA), the cell association and subsequent endocytic degradation of [125I]AGE-BSA were confirmed. To investigate the possible participation of scavenger receptors in the endocytosis of AGEs, these cells were incubated with AGE-BSA conjugated with colloidal gold particles (AGE-BSA-Au particles) and examined by immunoelectron microscopy with a monoclonal antibody for bovine macrophage scavenger receptors, D2. In these macrophages, AGE-BSA-Au particles were bound to the D2-positive scavenger receptors on the surface membrane, endocytosed, and directed to secondary lysosomes. The scavenger receptors were dissociated from the ligands in late endosomes and recycled via a trans-Golgi system to the cell surface membrane. These data suggest that scavenger receptors participate in the endocytic process of AGEs by macrophages.

Aging↗

PubMed1995

Phosphoinositide metabolism triggered by wheat germ agglutinin in human platelets.

The lectin wheat germ agglutinin (WGA) has been shown to elicit platelet functional responses such as aggregation and release reaction as a consequence of binding several cell surface glycoproteins in platelets, whereas physiological activators act on their specific receptors. To examine the mechanism of WGA-induced platelet activation, we analyzed phosphoinositide metabolism triggered by this lectin. The binding of WGA to human platelets induced a rapid and dose-dependent surge in phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) hydrolysis, as monitored by an increase in [Ca2+]i and phosphatidic acid production. Furthermore, it similarly elicited the synthesis of PtdIns(3,4)P2, which is a major 3-phosphorylated phosphoinositide in platelets. This 3-phosphorylated lipid generation induced by WGA was very strong and did not appear to be a consequence of the classical PtdIns(4,5)P2 hydrolysis. WGA also induced a marked increase in the degree of tyrosine phosphorylation of proteins in platelets, and this increase was correlated with the phosphoinositide metabolism, i.e. PtdIns(4,5)P2 breakdown and PtdIns(3,4)P2 synthesis. The non-selective inhibitor of protein kinases, staurosporine, inhibited similarly both the increase in tyrosine phosphorylation of several platelet proteins and the phosphoinositide changes in a dose-dependent manner. These findings suggest that both PtdIns(4,5)P2 hydrolysis and PtdIns(3,4)P2 synthesis are related to protein-tyrosine phosphorylation in platelets stimulated with WGA.

Blood Platelets↗

PubMed1995

[Enzyme amplification in enzyme immunoassay].

In enzyme immunoassay, the catalytic activity is determined by photometric assay of the substrate, and in a broad sense, it also includes fluorometric and chemiluminescent assays. Since enzyme immunoassay excells in specificity and detectability, it is widely applied to clinical tests which analyze various specimens. Here, we describe some of enzyme amplification methods including cyclic reactions, avidin-biotin reactions and enhanced chemiluminescent enzyme immunoassays. These methods have resulted in highly sensitive immunoassays, the level of which ranges from a attomole (1 x 10(-18) mol) to a zeptomole (1 x 10(-21) mol).

Avidin↗

PubMed1995

Immunohistochemical and ultrastructural detection of advanced glycation end products in atherosclerotic lesions of human aorta with a novel specific monoclonal antibody.

To elucidate the deposition of advanced glycation end products (AGEs) in aortic atherosclerosis, aortic walls were obtained from 25 autopsy cases and examined immunohistochemically and immunoelectron microscopically with a monoclonal antibody specific for AGEs, 6D12. Among the autopsy cases, atherosclerotic lesions were found in the aortas of 22 cases and were composed of diffuse intimal thickening, fatty streaks, atherosclerotic plaques, and/or complicated lesions. In these cases, intracellular AGE accumulation was demonstrated in the intimal lesions of aortic atherosclerosis in 12 cases. Compared with the diffuse intimal thickening, intracellular AGE accumulation was marked in the fatty streaks and atherosclerotic plaques. Immunohistochemical double staining with 6D12 and monoclonal antibodies for macrophages or muscle actin or a polyclonal antibody for scavenger receptors demonstrated that the AGE accumulation in macrophages or their related foam cells was marked in the diffuse intimal thickening and fatty streak lesions and that almost all macrophages and macrophage-derived foam cells possessed scavenger receptors. Immunoelectron microscopic observation revealed the localization of 6D12-positive reaction in lysosomal lipid vacuoles or electron-dense granules of the foam cells. These results indicate that AGE accumulation occurs in macrophages, smooth muscle cells, and their related foam cells.

Adult↗

PubMed1995

[Detection of platelet aggregates using light scattering].

Platelets play an important role in hemostasis and thrombosis. Evaluation of platelet function provides useful information on the diagnosis and cure of diseases associated with hemostasis and thrombosis. Among various platelet functions, platelet aggregometry is most widely used in clinical application. Platelet aggregation has been assessed by measuring the changes in the optical density of the platelet suspensions. However, this method has several shortcomings such as failure to detect the formation of small aggregates and lack of correlation between aggregate formation and changes in optical density. Thus, we have developed a new method of platelet aggregometry based on light scattering. This device emits laser beams against platelet aggregates and efficiently detects light scattering produced by these aggregates. The intensity and frequency of light scattering provides information as to the size and number of aggregates present in a limited area. By this method, we were able to determine several different modes of inhibitory effects on platelet aggregation. The high sensitivity of this method also allowed us to detect slight platelet activation, which had not been possible by the conventional method using changes in optical density. Clinical application of this method revealed frequent occurrence of spontaneous aggregation in diabetic patients and a close relationship between this phenomenon and diabetic complications.

Diabetes Mellitus↗

PubMed1994

Effects of sulfonylurea agents on platelet arachidonic acid metabolism; study on platelet homogenates.

Effects of three sulfonylurea agents on arachidonic acid metabolism of platelet homogenates were evaluated using HPLC. Gliclazide had no significant inhibitory effects on arachidonic acid metabolism. Glibenclamide and glimepiride both inhibited the production of cyclooxygenase-related metabolites, thromboxane B2 (TXB2) and 12-hydroxy 5,8,10-heptadecatrienoic acid (HHT), whereas 12-hydroxy 5,8,10,14-eicosatetraenoic acid (12-HETE), a 12-lipoxygenase-related product, was unaffected. These findings confirmed part of our previous report using intact platelets, except that we found in the present study that glibenclamide had no inhibitory effect on 12-lipoxygenase.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗

PubMed1994

Synthesis of phosphatidylinositol 3,4-bisphosphate is regulated by protein-tyrosine phosphorylation but the p85 alpha subunit of phosphatidylinositol 3-kinase may not be a target for tyrosine kinases in thrombin-stimulated human platelets.

To elucidate the mechanism involving synthesis of phosphatidylinositol 3,4-bisphosphate (PtdIns(3,4)P2), which is the main species of 3-phosphorylated phosphoinositides in activated blood platelets, we observed a correlation among protein-tyrosine phosphorylation, protein kinase C (PKC) activation, and PtdIns(3,4)P2 synthesis in these anucleate cells. Thrombin (1 U/ml) elicited marked protein-tyrosine phosphorylation, PKC activation, and PtdIns(3,4)P2 synthesis. In contrast, 1 microM 12-O-tetrade-canoylphorbol 13-acetate barely induced tyrosine phosphorylation and PtdIns(3,4)P2 synthesis although it strongly activated PKC. A variety of kinase inhibitors were tested for their ability to inhibit the thrombin effects. Both staurosporine and tyrphostin inhibited thrombin-stimulated tyrosine phosphorylation and PtdIns(3,4)P2 synthesis. H-7, which specifically, although weakly, inhibited PKC activation, had no effect on tyrosine phosphorylation and PtdIns(3,4)P2 production. Among the various kinase inhibitors tested, staurosporine was the most potent inhibitor of protein tyrosine phosphorylation and PtdIns(3,4)P2 synthesis, and there was a good correlation of the inhibition between these two parameters, although it also inhibited PKC activation. To examine the involvement of PtdIns 3-kinase, which is believed to play an important role in 3-phosphorylated phosphoinositide synthesis, we studied tyrosine phosphorylation and the association with tyrosine-phosphorylated proteins of the p85 alpha subunit of PtdIns 3-kinase in thrombin-stimulated platelets. We did not detect tyrosine-phosphorylated protein by Western blotting where p85 alpha was located. Similarly, when platelet lysates were precipitated with anti-p85 alpha antibodies and then blotted with anti-phosphotyrosine antibodies, tyrosine-phosphorylated p85 alpha was undetectable. Furthermore, when the cell lysates were precipitated with anti-phosphotyrosine antibodies, no p85 alpha was found in the immunoprecipitates. These results show that PtdIns(3,4)P2 synthesis in stimulated platelets is mediated by tyrosine phosphorylation, as it is in proliferating cells, but the p85 alpha subunit of PtdIns 3-kinase may not be a target for tyrosine kinases and that staurosporine, though non-specific, would be a useful tool for elucidating signal transduction involving D-3-phosphorylated phosphoinositide generation and protein-tyrosine phosphorylation in blood platelets.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1994

Detection of platelet aggregates with a particle counting method using light scattering.

A novel method to detect platelet aggregation by means of the particle counting technique using light scattering has been developed. An optical device designed to focus on a limited area of platelet-rich plasma measured the intensity of light scattered by particles passing through the area, minimizing multiple light scattering. The use of polystyrene spheres of different diameters confirmed that the light scattering intensity increases in proportion to the particle size in a suspension. Platelet activation induced by various agonists resulted in light scattering of higher intensities, which correlated well with the number and size of aggregates as observed under a microscope. These findings confirmed that the intensity of light scattering detected by the new device provides information on the number and size of aggregates in a suspension. The new method was compared with conventional platelet aggregometry using overall light scattering or changes in light transmission (optical density). The new device appeared to be particularly sensitive to small aggregates such as those formed in platelet activation induced by low concentrations of agonists. Furthermore, the new method has an advantage over the conventional aggregometry, in that it allows the aggregate size distribution and the extent of aggregation to be estimated.

Adenosine Diphosphate↗

PubMed1994

Phosphatase inhibitors suppress Ca2+ influx induced by receptor-mediated intracellular Ca2+ store depletion in human platelets.

The effects of three phosphatase inhibitors including okadaic acid, calyculin A and tautomycin were evaluated on platelet Ca2+ mobilization. Calyculin A and tautomycin at appropriate concentrations appeared to have a selective inhibitory effect on thrombin-induced Ca2+ influx, but not on [Ca2+]i release from intracellular Ca2+ storage sites. In contrast, pretreatment with okadaic acid at concentrations that effectively lowered Ca2+ influx also suppressed Ca2+ release from intracellular Ca2+ stores. In a system that specifically evaluates the effects of agents on Ca2+ influx induced by the Ca(2+)-depleted state of intracellular Ca2+ storage sites, the three phosphatase inhibitors attenuated Ca2+ influx in a dose dependent manner and showed complete inhibition at appropriate concentrations. These findings suggest that protein phosphorylation/dephosphorylation plays an important role in mediating signals to open Ca2+ channels when Ca2+ depletion in intracellular Ca2+ stores is caused by thrombin. In contrast, Ca2+ influx induced by thapsigargin, a Ca(2+)-ATPase inhibitor, was only partially suppressed by pretreatment with each of the three phosphatase inhibitors. Based on these findings, we suggest that the Ca(2+)-depleted state of intracellular Ca2+ stores by thapsigargin induces the opening of Ca2+ channels via phosphatase inhibitor-insensitive pathways. All the phosphatase inhibitors, at the highest concentrations tested in the present study, only partially inhibited Mn2+ entry induced by thrombin. These findings suggest that there are at least two types of divalent ion channels on platelet plasma membranes and that one of them, that preferentially allows Mn2+ entry, is resistant to the inhibitory effects of phosphatase inhibitors.

Antifungal Agents↗

PubMed1994

Effect of twinning and supplemental iron-saturated lactoferrin on iron status of newborn calves.

Data from 53 calves by embryo transfer were collected to determine the effect of twinning and supplemental Fe-saturated lactoferrin or FeSO4 for 5 d after parturition on iron status of calves. Blood hematocrit and hemoglobin of multiple calves born from multiparous cows at d 1 postpartum were lower than those of single calves born from multiparous cows, although those of their dams were not different. Plasma Ca, inorganic P, Mg, Zn, and Cu were similar for single and multiple calves or for calves born from primiparous and multiparous cows. Blood hematocrit and hemoglobin of untreated calves decreased from 1 to 6 d postpartum. Blood hematocrit of calves treated with 40 mg of Fe/d as FeSO4 increased from 1 to 10 d postpartum, and blood hemoglobin of calves treated with 20 or 40 mg of Fe/d as ferrous Fe increased from 1 to 10 d postpartum. Blood hematocrit and hemoglobin of calves treated with 20 mg of Fe/d as Fe-saturated lactoferrin remained nearly constant for 10 d postpartum. Serum Fe of calves increased immediately after the treatment with 20 or 40 mg of Fe as FeSO4, but serum Fe of calves treated with lactoferrin was not affected. Thus, ferrous Fe may be more effective than Fe-saturated lactoferrin in elevating blood hematocrit and hemoglobin in newborn calves.

Animal Feed↗

PubMed1994

[Immunohistochemical study on keratin expression of uterine reserve cells].

An immunohistochemical expression in the reserve cells of the uterine cervix using monoclonal antibodies of cytokeratin which detected the different subtypes of keratin was studied. Although the reserve cells were positive for all the four cytokeratin antibodies (CAM5.2, M-20, M-888, M-630), different immunoreactivity was found as follows: CAM5.2 reacted uniformly and intensely in the cervical glands, but weak in the reserve cells. M-20 reacted similar to that of CAM5.2 in the cervical glands, but was weaker stained in the reserve cells than with CAM5.2. M-888 reacted uniformly and intensely in both the cervical glands and reserve cells. M-630 reacted only in the reserve cells, but seldom in the cervical glands. Hence, CAM5.2 and M-20, which detected No.8 and No.18 of antiserum for low-molecular weight cytokeratin, reacted more weakly in the reserve cells than in the cervical glands, and M-630, which detected No.5 and No.14 of antiserum for high-molecular weight cytokeratin, reacted uniformly and intensely in the reserve cells. That results suggested the reserve cells revealed the expression as the stratified squamous epithelium. As for cell proliferation on the cervical glands and reserve cells, the positive nuclear staining for proliferating cell nuclear antigen (PCNA) was found in both of them, especially in the cervical glands just above the reserve cells. Therefore, the reserve cells had characteristics of squamous cell epithelium and developed to metaplastic cells.

Antibodies, Monoclonal↗