274 POTENTIAL OF BOVINE MARROW STROMAL CELLS CULTURED AT DIFFERENT PASSAGES TO DIFFERENTIATE INTO ADIPOCYTE-LIKE CELLS

Bovine marrow stromal cells (MSC) would serve as a preclinical large-animal model for investigating the use of the adult pluripotent cells MSC for human cell therapies, but the information is limited. In this study, adipocytic differentiation was examined in bovine MSC at different passages (psg) after various adipogenic treatments, as the first step in characterizing the multilineage differentiation potential during an extensive culture. Bovine MSC were cultured from the femurs of 3-month-old Holstein calves using a previously described method with slight modifications (Xiang et al. 2001 Chin. J. Pathophysiol. 17, 598–601). The MSC at psg 2, 5, 10, 15, and 20 (total cell culture periods of 10, 19, 34, 49, and 64 days, respectively, 4 × 103 cells cm–2) were cultured for 2 days post-psg. Previously, we found that most of mouse MSC became adipocyte-like cells after they were cultured with a base medium (DMEM, 4.5 g L–1 glucose, plus 10% FBS) containing horse serum (HS) for 5 weeks. Therefore, the bovine MSC at each psg (70% confluence) were then cultured in the base medium containing 0.1 μm dexamethasone, 0.1 mm 3-isobutyl-1-methylxanthine, 0.2 mm indomethacin, and 10 μg mL–1 insulin [hormonal-mixture (HM) group], the base medium containing 15% HS (HS group), or the base medium (control group) for adipogenic induction. The cells were stained with oil red O after being cultured in the respective medium for 1, 3, or 5 weeks. In this study, all cells containing oil red O-stained lipid droplets (LD) were counted as ‘oil red O-positive (OP) cells’, regardless of the size and number contained. The rate of OP cells in each group was determined as follows. In the dishes, the total number of cells (60 to 100 cells) and OP cell number were counted in a randomly selected microscopic field (200×), and the rate of OP cells was calculated. A total of 10 random fields of view were examined, and the mean value was obtained for each group. Data were analyzed by ANOVA. In the HM group, OP cells were detectable about Day 7 and were clearly visible by 2 weeks. After 5 weeks, OP cell rates were significantly greater (P < 0.05) in the cells at psg 2 and 5 than in those at psg 10, 15, and 20 (71 and 70% v. 66, 63, and 64%). In the HS group, cytoplasmic LD was detectable about Day 10 and the number increased gradually by 3 weeks. After 5 weeks, OP cell rate was significantly greater (P < 0.05) in the cell at psg 2, 5, and 10 than in those at psg 15 and 20 (53, 57, and 51% v. 47 and 39%). Also, the size and number of LD in each cell tended to be lower in the HS group than in the corresponding HM group. In the control group, 4–5% of the cells were OP after 5 weeks. These results suggest that the ability of bovine MSC to differentiate into adipocyte-like cells decreased after long-term culture, and that horse serum was capable of inducing adipocytic differentiation of bovine MSC in vitro, but its efficacy was less than that of the hormonal mixture. Further studies to detect adipocyte-specific markers, such as G3PDH activity and aP2 expression, from these cells are needed for the quantitative analysis of the differentiation.

45 DEVELOPMENT OF BOVINE NUCLEAR TRANSFER EMBRYOS DERIVED FROM ADULT MARROW STROMAL CELLS AND FETAL MUSCLE CELLS

The use of less differentiated cells, such as marrow stromal cells (MSCs), as the nuclear donor may increase the efficiencies of somatic cell cloning in cattle. Healthy offspring was produced from bovine MSCs (Kato et al. 2004 Biol. Reprod. 70, 415–418); however, there is little information that directly compared the post-implantation survival among the clones originated from MSCs and other somatic cells. The objective of this study was to evaluate the developmental potential in vitro and in vivo of bovine NT embryos derived from adult MSCs and fetal muscle cells (FMCs). Primary cell populations of MSCs and FMCs were obtained from the femurs of 8- and 12-months-old Holstein cows (MSC1 and MSC2 groups, respectively) and a Holstein fetus at 8 months of gestation (FMC group), respectively. They were used as donor cells for the NT procedure (Murakami et al. 2005 Cloning Stem Cells 7, 77–81) at passages 1 to 3. Briefly, oocytes collected from cow ovaries were enucleated at 20 h post-in vitro maturation (IVM), and the donor cell was placed into the perivitelline space. The couplets were fused electrically, activated (10 μg mL–1 cycloheximide; 4 h), and cultured in CR1aa medium. Development in vitro of these embryos is summarized in Table 1. Data were analyzed by ANOVA. The fusion rates were higher in the MSC groups than in the FMC group. The rate of cleaved embryos was significantly lower (P < 0.05) in the MSC1 group than in the other groups. However, there were no significant differences among the groups in the rates of development into morulae/blastocysts on Day 6. A total of 8 and 3 fresh good quality Day 6 embryos in the MSC1 and FMC groups, respectively, were nonsurgically transferred to 6 naturally cycling Holstein females 6 days after estrus (3 recipients/group, 1–3 embryos/female). On Day 30 of gestation, none of the recipients were pregnant in the FMC group, while 2 recipients in the MSC1 group were diagnosed as pregnant via ultrasonography; they remained pregnant on Day 80 of gestation. In addition, a total of 4 Day 7 embryos cryopreserved in 1.8 m ethylene glycol plus 0.05 m trehalose were directly transferred to 4 synchronized recipients after thawing (1 embryo/female) in the MSC1 group. Of those, 2 females were pregnant on day 30 of gestation. These results indicate that the developmental potential in vitro of bovine NT embryos derived from adult MSCs was comparable to that of the embryos derived from fetal muscle cells, and that pregnancies were produced after transfer of the fresh and frozen–thawed NT embryos derived from the MSC, but the sample size was small. Further studies with more replicates are needed to evaluate viability in vivo of these cloned embryos for comparative purposes. Table 1.Development in vitro of bovine NT embryos derived from different cell types

83 DEVELOPMENT OF BOVINE IN VITRO-PRODUCED BLASTOCYSTS AFTER CRYOPRESERVATION IN CHEMICALLY DEFINED SOLUTIONS AND ONE-STEP DILUTION

Efficient embryo cryopreservartion using a protein-free defined solution would be beneficial for hygienic commercial embryo transport. In addition, one-step rehydration of frozen–thawed embryos could allow direct transfer of cryopreserved embryos after thawing. The objective of this study was to assess the viability in vitro of bovine in vitro-produced (IVP) embryos after freezing and thawing in a base cryoprotective solution [modified synthetic oviduct fluid (mSOF) medium containing 1.8 m ethylene glycol and 0.05 m trehalose] supplemented with various concentrations of polyvinyl alcohol (PVA). The methods used for in vitro embryo production and embryo cryopreservation were modified from those described previously (Murakami et al. 1998 Cryobiology 36, 206–212). Briefly, oocytes collected from cow ovaries were matured, fertilized in vitro for 5 h, and cultured in mSOF containing 0.4% bovine serum albumin (BSA) at 38.5�C in a humidified atmosphere of 5% CO2, 5% O2, and 90% N2 (reduced-O2 atmosphere; Day 0). On Day 3, only cleaved embryos were co-cultured with bovine cumulus cells in mSOF containing 5% fetal bovine serum (FBS) in a humidified atmosphere of 5% CO2 in air. On Day 7, embryos that reached the blastocyst stage were selected and immersed directly into the base cryoprotective solution supplemented with 0.4% BSA (0.4BSA group, the protein-containing control group) or 1.5, 3.0, or 6.0% PVA (1.5PVA, 3PVA, and 6PVA groups, respectively) at room temperature. After exposure to solution, embryo–cryoprotectant solutions were loaded into 0.25-mL plastic straws and cryopreserved by the standard slow freezing method (about 60 to 100 embryos in each group). The frozen straws were placed in air for 10 s, and plunged into a 38.5�C water bath for 10 s; the contents were expelled into a plastic dish. The embryos were then transferred directly to pre-incubated minimum essential medium alpha medium containing 5% FBS and MEM nonessential amino acids solution (mαMEM) for one-step rehydration. These frozen.thawed embryos were washed well and cultured in fresh mαMEM in a reduced-O2 atmosphere for 3 days to examine the developmental potential in vitro. Data were analyzed by ANOVA. The percentage of re-expanded embryos after freezing and thawing was significantly higher (P < 0.05) in 0.4BSA and 1.5PVA groups than in the 3PVA and 6PVA groups (95.4% in 0.4BSA and 90.9% in 1.5PVA v. 73.4% in 3PVA and 57.7% in 6PVA). In addition, there was no significant difference between 0.4BSA and 1.5PVA groups in the percentage of embryos developed into hatched blastocysts (82.0 v. 80.2%), but the percentage decreased with increasing PVA concentration (51.1% in 3PVA and 29.3% in 6PVA, respectively). These results suggest that the biological product BSA added in our standard cryoprotective solution can be replaced with 1.5% PVA to support similar viability of frozen.thawed bovine IVP embryos after one-step dilution. Further studies, including direct transfer of these frozen embryos after thawing, are needed to substantiate these results.

24 DEVELOPMENT OF BOVINE CLONED EMBRYOS PRODUCED BY NUCLEAR TRANSFER OF EMBRYONIC CULTURED CELLS ISOLATED FROM SOMATIC CELL NUCLEAR TRANSFER BLASTOCYSTS

Embryonic stem (ES) cells derived from somatic cell nuclear transfer (NT) bovine embryos would increase the utility of the cow as a large animal model for human cell therapy. They would also be useful for studies of cell differentiation. Such cells exhibit full pluripotency, and cloned offspring were obtained from them following a second NT in mice, indicating that the reprogramming that produced pluripotent ES cells could be reversed (Wakayama et al. 2001 Science 292, 740–743). The objective of this study was to examine if there would be any beneficial effects of using somatic cell NT-derived embryonic cultured cells as donors for cloning in cattle. Cloned embryos were produced from a single cell line of bovine fetal fibroblasts (FF) and adult ear-tip cells (AEC) (passages 1 to 5) by NT, as described previously (Dong et al. 2004 Asian–Aust. J. Anim. Sci. 17, 168–173). NT embryos that reached the blastocyst stage were cultured separately to isolate embryonic cultured cells derived from FF (NT-FF) and AEC (NT-AEC) according to previous methods (Dong et al. 2003 Acta Genet. Sin. 30, 114–118). More than 80% of the generated embryonic cultured cells stained positive for alkaline phosphatase. Embryonic cells cultured for 7 to 35 days were used as the donor cells for NT in the NT-FF and NT-AEC groups. Cloned embryos were produced using individual cell lines of FF, AEC, NT-FF, and NT-AEC (passages 1 to 5, putative cell cycle stage of G0 or G1) as donor cells, and their development in vitro is summarized in Table 1. The FF and AEC groups include data from the initial round of NT. The rates of fusion and embryo development were compared by chi-square analysis. Duncan's multiple range test was used to compare the mean cell numbers of blastocysts. The percentage of embryos that developed into blastocysts was significantly higher (P < 0.05) in the FF group than in the AEC group. Interestingly, we observed that the developmental potential in vitro and the mean cell number of blastocysts tended to be higher in the NT-FF and NT-AEC groups than in the FF and AEC groups. A total of 15 and 6 good quality Day 7 embryos in the NT-FF and NT-AEC groups were nonsurgically transferred to 5 and 3 synchronized recipients (2 to 3 embryos/female), respectively. On Day 30 of gestation, 3 (60%) and 1 (33%) females in the NT-FF and NT-AEC groups, respectively, were diagnosed as pregnant via ultrasonography. One (20%) recipient cow in the NT-FF group remained pregnant at Day 60 of gestation, but lost the pregnancy by Day 90. These results suggest that cloning of bovine embryonic cultured cells generated from fetal and adult somatic cells by NT can produce transferable embryos and initiate pregnancies, although none of the pregnancies has developed beyond the first trimester at this time. Table 1. Development in vitro of bovine NT embryos produced from different donor cell types

Growth factors and growth hormone enhance in vitro embryo production and post-thaw survival of vitrified bovine blastocysts

The objective of this study was to assess the influence of specific growth factors and growth hormone (GH) in the culture medium on in vitro embryo production and post-thaw survival of vitrified blastocysts. In total, 1673 bovine oocytes were used for evaluating the nuclear status of the oocytes after in vitro maturation (n=560) or for in vitro fertilization (IVF, n=1113) and distributed in five treatment groups: (1). medium only control; (2). activin (10 ng/ml); (3). epidermal growth factor (EGF) (10 ng/ml); (4). insulin 5 microg/ml and (5). GH (100 ng/ml). There was an increase (P<0.05 and P<0.01, respectively) in the percentage of oocytes that reached meta phase II, developed to blastocysts and hatched, as well as in the blastocyst cell number in the groups treated with activin, EGF and GH compared to controls. There was no significant difference between insulin and control groups. A total of 465 blastocysts were vitrified in a three-step protocol using ethylene glycol and polyvinylpyrrolidone. After thawing, embryos were cultured in five treatments groups as described above. Groups EGF and GH had higher (P<0.05) survival rates with a mean blastocyst survival of 95.0+/-1.5 and 93.1+/-3.5%, respectively, while mean hatching rate was higher for EGF and activin groups (75.3+/-3.4 and 62.0+/-3.2%, respectively). Thawed control blastocysts had a mean cell count of 52.7+/-3.3%. With the exception of insulin, all growth factors and GH tested showed higher (P<0.01) total cell numbers when compared to controls. In conclusion, addition of growth factors and GH in the culture media has favorable effects on in vitro maturation, in vitro embryo production, and post-thaw survival of vitrified blastocysts.

Comparison of the effects of using standard and simple portable CO2 incubators on the in vitro developmental competence of bovine embryos reconstituted by somatic cell nuclear transfer

In an attempt to determine the cultural factors that would improve cloning efficiency, we compared the effects of two incubation systems-a simple portable system and a standard CO2 incubator-on the production of bovine embryos by electrofusion of quiescent fetal fibroblast nuclei to enucleated oocytes matured in vitro. While the temperature (38.5 degrees C) and CO2 concentration (5%) were similar in both systems, the portable incubator operated in a vacuum of 300 mmHg and at an O2 level of 8-10%, which is lower than the standard. Although there were no significant differences between the two systems in terms of in vitro oocyte maturation (MII stage), fusion rates, and the number of cells in Day 7 blastocysts, significantly higher proportions of nuclear-transferred oocytes cleaved (P < 0.05) and developed to the blastocyst stage (P < 0.01) in the portable incubator (70.5 +/- 0.6 and 36.1 +/- 1.4%, respectively) than in the standard incubator (64.1 +/- 3.2 and 23.5 +/- 1.4%, respectively). Following the transfer of six blastocysts from the portable incubator group to three recipients, survival rates on Days 60, 90, and 120 were 100, 66.7 and 33.3%, respectively. This relatively high early embryonic loss may be associated with multiple pregnancy complications or other abnormalities of placentation frequently observed in cloned embryos. Further studies using this portable incubator system are needed to determine the optimum levels of O2, CO2, and air pressure.

Improvement of the culture conditions for in vitro production of cattle embryos in a portable CO2 incubator

The effects of different concentrations of growth hormone (GH) on in vitro maturation (IVM), fertilization (IVF) and culture (IVC) of bovine oocyte/embryos in CR1aa or CR2aa media using a simple CO2 incubator were investigated. The IVM/IVF/IVC of oocytes were carried out in the presence of 0, 50, 100 and 200 ng/ml GH in the medium. The proportion of metaphase II oocytes was significantly higher (p < 0.05) in 200 ng/ml compared with 0 ng/ml GH in CR1aa medium (59 versus 85%, respectively), but this effect was not observed under CR2aa. Higher concentrations of GH yielded lower rates of unfertilized ova and thus superior cleavage rates (36.5 +/- 0.2 and 63.5 +/- 2.0% versus 17.5 +/- 0.2 and 82.5 +/- 1.5% or 40.4 +/- 0.6 and 59.6 +/- 1.4% versus 16.6 +/- 1.2 and 83.4 +/- 6.2% for 0 and 200 ng/ml GH in portable or ordinary incubator, respectively) in CR1aa. This dose-dependent effect was also observed in the percentages of transferable embryos, although not statistically different (17.2 +/- 1.7 versus 27.3 +/- 1.8% and 16.6 +/- 3.1 versus 26.0 +/- 1.4%, for 0 versus 200 ng/ml GH in portable and ordinary incubator, respectively). In contrast to the CR1aa, different concentrations of GH in CR2aa medium did not increase either fertilization or cleavage rates. In fact, higher concentrations of GH in this medium negatively affected the rate of transferable embryos. Hence, percentages of transferable embryos obtained in the portable incubator under 0 or 50 ng/ml GH were higher (p < 0.05) compared with those obtained in 100 or 200 ng/ml GH (35.4 +/- 5.7 or 40.5 +/- 5.4% versus 22.4 +/- 2.4 or 15.5 +/- 2.1%, respectively). There was however, no significant difference in the rate of transferable embryos in an ordinary incubator employing CR2aa medium, but the trend was more or less similar to that observed in the portable incubator. Despite the fact that relatively fewer oocytes were employed for the culture in the ordinary incubator, overall results observed employing the simple portable CO2 incubator were within the range of those obtained in an ordinary incubator: implying that the simple portable incubator can effectively be employed for the in vitro production of bovine embryos under field conditions.

The effect of prefreezing the diluent portion of the straw in a step-wise vitrification process using ethylene glycol and polyvinylpyrrolidone to preserve bovine blastocysts

A total of 678 bovine blastocysts, which had been produced by in vitro maturation, fertilization, and culture, were placed into plastic straws and were vitrified in various solutions of ethylene glycol (EG) + polyvinylpyrrolidone (PVP). Part of the straw was loaded with TCM199 medium + 0.3 M trehalose as a diluent; the diluent portions of the straw were prefrozen to either -30 or -196 degrees C. Then, the embryos suspended in the vitrification solution were pipetted into the balance of the straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were warmed for 3 s in air and 20 s in a water bath at 39 degrees C and then agitated to mix the diluent and cryoprotectant solution for 5 min followed by culture in TCM199 + 10% FCS + 5 + microg/ml insulin + 50 microg/ml gentamycin sulfate for 72 h. Variables that were examined were the time of exposure to EG prior to vitrification, the PVP concentration, and the temperature of exposure to EG + PVP prior to vitrification. Survival and hatching rates of the blastocysts exposed to 40% EG in four steps at 4 degrees C were higher than those of embryos exposed in two steps (81.3 +/- 4.3% and 80.2 +/- 3.4% vs 67.6 +/- 4.5% and 71.5 +/- 4.7%, respectively; P < 0.05). The same indices were superior following vitrification-thawing of the blastocysts in 40% EG + 20% PVP than it was in 40% EG + 10% PVP (76.1 +/- 5.5% vs 63.7 +/- 1.8%; P < 0.05; and 61.6 +/- 6.0% vs 70.5 +/- 4.7%; P < 0.01, respectively). Exposure to the vitrification solution (40% EG + 20% PVP) at higher temperatures (37.5 degrees C vs 4 degrees C) reduced both survival and hatching rates (45.8 +/- 6.9% vs 83.9 +/- 4.4% and 41.5 +/- 1.8% vs 64.0 +/- 4.7%, respectively; P < 0.001). These results indicate that blastocysts vitrified after prefreezing the diluent portions of the straws do favor developmental competence of in vitro produced embryos.

Bovine Blastocysts Obtained from Reconstructed Cytoplast and Karyoplasts Using a Simple Portable CO2 Incubator

To enable both the multiplication of elite livestock and the engineering of transgenic animals for various agricultural and biochemical purposes, scientists around the world are intensively studying efficient ways of improving developmental competency of bovine embryos reconstructed by somatic cell nuclear transfer. Because it is widely accepted that culture conditions along with many other factors contribute to the developmental competency of reconstructed embryos, this preliminary study was designed to test whether or not bovine reconstructed embryos could develop in vitro using a simple portable CO(2) incubator. CO(2) and O(2) gas tensions and air pressure can be varied using this system. The parameters used in the five conducted trials were low CO(2) (2-5%) and O(2) (8-10%) gas tensions, and negative air pressure (of 300 mm Hg). Chamber temperature was maintained at 38.5 degrees C. Bovine fetal fibroblasts were used as donor karyoplasts and were fused into microsurgically enucleated M II oocytes followed by activation and culture. From the 250 enucleated oocytes, 217 (86.8%) fused, 183 (73.2%) cleaved, and 43 (17.2%) developed to the blastocyst stage. While relatively low developmental rates were achieved, technical proficiency may have been a contributing factor. Further studies using this system are needed to determine optimal levels of O(2), CO(2), and air pressure.

Reduced IL-10 secretion by CD4+ T lymphocytes expressing mutant cystic fibrosis transmembrane conductance regulator (CFTR)

Expression of the CFTR protein is thought to be physiologically important only in exocrine epithelial cells. However, chronic respiratory inflammation and infection remain unexplained phenomena in disease pathogenesis. Non-transformed, antigen-responsive CD4+ T cells cloned from healthy controls and CF patients homozygous or heterozygous for the delta F508 mutation transcribed CFTR mRNA and expressed immunoreactive cytoplasmic CFTR protein. T cell clones (TCC) from controls and CF patients displayed equivalent Ca(2+)-mediated Cl- current; however, TCC from patients with CF but not controls displayed defective cAMP-mediated Cl-current. Although CF-derived TCC preserved mitogen and antigen proliferative responses and specificity to tetanus toxoid epitopes, they selectively secreted approximately 45% less IL-10 compared with control TCC after activation with concanavalin A (Con A) (624 +/- 101 versus 1564 +/- 401 pg/ml per 10(6) cells, respectively; P = 0.04) or anti-CD3/phorbol ester (5148 +/- 1634 versus 11788 +/- 2390 pg/ml; P = 0.05). This difference was independent of atopy. Secretion of interferon-gamma, IL-2, and IL-4 was comparable in CF and control TCC after both forms of activation, while IL-5 was reduced in CF TCC following anti-CD3/phorbol myristate acetate (PMA) but not after Con A. We conclude that expression of mutant CFTR in human TCC is accompanied by ion channel dysfunction characteristic of the CF phenotype, and is accompanied by a reduction in IL-10 secretion after polyclonal activation. It is possible that disruption of IL-10-mediated anti-inflammatory homeostasis may contribute to early onset sustained inflammation in CF airways.

Expression and activities of class IV alcohol dehydrogenase and class III aldehyde dehydrogenase in human mouth

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are the principal enzymes responsible for the oxidation of ingested ethanol in humans. To study these two enzymes in surgical specimens of attached gingiva and tongue, we have examined the isozyme patterns by agarose isoelectric focusing and determined the enzyme activities. Class IV mu-ADH, class III chi-ADH, and class III ALDH3 were detected in the oral mucosa tissues. Gingival mu-ADH exhibited a pH optimum for ethanol oxidation at 10 and the K(m) value for ethanol (pH 7.5) was estimated to be 27 mM. At pH 7.5 and 30 degrees C, the ADH activities in the gingiva and tongue samples were determined to be 90.0 +/- 5.8 (mean +/- SE; n = 24) and 50.6 +/- 5.1 (n = 3) nmol/min/g tissue (at 33 mM ethanol), and 138 +/- 11 and 55.1 +/- 4.7 nmol/min/g tissue (at 500 mM ethanol), respectively. The ALDH activities at 20 mM acetaldehyde were determined to be 169 +/- 19 and 50.3 +/- 8.1 nmol/min/g tissue for the gingiva and tongue, respectively. We conclude that ethanol can be significantly metabolized in human attached gingiva and lingual mucosa by mu-ADH. The result also suggests that, due to lacking activity of low K(m) ALDH2 and ALDH1, cytotoxic metabolite acetaldehyde may be involved in the etiology of alcohol-related oral injury.

The use of immediate frozen autogenous mandible, for benign tumour mandibular reconstruction

Reimplantation of frozen autogenous lesioned mandible was performed in 31 patients with mandibular bone cysts and tumours. 26 reimplanted grafts survived without complications following surgery. Two cases had postoperative infections which were resolved following appropriate antibiotic treatment. Three grafts were removed due to the severe infection and wound dehiscence. The follow-up from 6 months to 4 years showed that there was no recurrence of the primary lesion in the 28 successful cases. Satisfactory facial contour after surgery was achieved in 19 patients, while other patients showed relatively mild facial disfigurement. The inferior alveolar nerve was repaired in 4 cases and a functional evaluation was made using an acupuncture pressure tester.

Calcium- and CaMKII-dependent chloride secretion induced by the microsomal Ca(2+)-ATPase inhibitor 2,5-di-(tert-butyl)-1,4-hydroquinone in cystic fibrosis pancreatic epithelial cells

Microsomal Ca(2+)-ATPase inhibitors such as thapsigargin (THG), cyclopiazonic acid (CPA) and 2,5-di-(tert-butyl)-1,4-hydroquinone (DBHQ) have been shown to inhibit Ca2+ reuptake by the intracellular stores and increase cytosolic free Ca2+ ([Ca2+]i). DBHQ is a commercially available non-toxic synthetic compound chemically unrelated to THG and CPA. In this study, we tested the feasibility of utilizing DBHQ to improve Cl- secretion via the Ca(2+)-dependent pathway, in the cystic fibrosis (CF)-derived pancreatic epithelial cell line CFPAC-1. DBHQ stimulated 125I efflux and mobilized intracellular free Ca2+ in a dose-dependent manner. The maximal effects were seen at concentrations of 25-50 microM. DBHQ (25 microM) caused a short-term rise in [Ca2+]i in the absence of ambient Ca2+, and a sustained elevation of [Ca2+]i in cell monolayers bathed in the efflux solution (1.2 mM Ca2+), which was largely attenuated by Ni2+ (5 mM). Bath-application of DBHQ induced an outwardly-rectifying whole-cell Cl- current, which was abolished by pipette addition of BAPTA (5 mM) or CaMK [273-302] (20 microM), an inhibitory peptide of multifunctional Ca2+/calmodulin-dependent protein kinase (CaMKII). Pretreatment of monolayers of CFPAC-1 cells with DBHQ for 4-5 min significantly increased the Ca(2+)-independent or autonomous activity of CaMKII assayed in the cell homogenates. Thus, DBHQ appears to enhance Cl- channel activity via a Ca(2+)-dependent mechanism involving CaMKII. Pretreatment of CFPAC-1 cells with up to 50 microM DBHQ for 6 h did not cause any detectable change in cell viability and did not significantly affect the cell proliferation rate. These results suggest that appropriate selective microsomal Ca(2+)-ATPase inhibitors may be therapeutically useful in improving Cl- secretion in CF epithelial cells.

[Effects on the growth and development of mandible with different treatment following condylar neck fracture in rat]

The condylar necks of young rats are fractured on this experiment.Fractures are treated with nonfixation and fixation,The growth and development of mandible can be interrupted in two groups,with a relatively small in condylar head,a relatively thick in condylar neck.A coronoid and a mandible length are relatively short.But the growth and development of mandible almost are completed,bilateral mandibles are almost symmetry except for ramus.The difference are not found in between two groups.The results of this study implied that young condylar neck fracture may be treated by conservation.

Activation of CFTR chloride current by nitric oxide in human T lymphocytes

Nitric oxide, which is produced by cytokine-activated mononuclear cells, is thought to play an important role in inflammation and immunity. While the function of nitric oxide as a direct cytotoxic effector molecule is well established, its function as a transducer molecule in immune cells is not. By use of whole-cell patch clamp recordings, we show that nitric oxide activates cystic fibrosis transmembrane conductance regulator CI- currents in normal human cloned T cells by a cGMP-dependent mechanism. This pathway is defective in cystic fibrosis-derived human cloned T cells. These findings not only delineate a novel transduction mechanism for nitric oxide but also support the hypothesis that an intrinsic immune defect may exist in cystic fibrosis.

Relationship of gingival calculus and bleeding on probing in CPITN code 2 sextants

The aims of this study were twofold: firstly, to evaluate the relationship of supra- or subgingival calculus and bleeding on probing (BOP) in sextants coded 2 in the Community Periodontal Index of Treatment Needs (CPITN); and secondly, to compare the differences in four investigations in Taiwan, Hong Kong, Japan and Norway. In a national survey, a total of 2658 Chinese dentate adults were examined by using modified CPITN in the Taiwan area from 1985 to 1987. Sextants given Code 2 were divided into four subclassifications: supragingival calculus with bleeding (I+), supragingival calculus without bleeding (I-), subgingival calculus with bleeding (II+) and subgingival calculus without bleeding (II-). The results showed that of the 9394 sextants given Code 2, the highest percentage (70%) were characterized by the presence of subgingival calculus with bleeding and the lowest percentage (4%) by supragingival calculus with bleeding. The ratio of sextants coded 2 with only supragingival calculus versus subgingival was 1:6.2. The bleeding to nonbleeding ratio of sextants coded 2 in this study was similar to the Hong Kong study. However, differences among Taiwan, Japan and Norway were found. The results indicated that sextants with subgingival calculus had a higher tendency to BOP, with a ratio of 4:1. Those with supragingival calculus had a ratio of 3:7. We conclude therefore, that it is essential to scale teeth to remove subgingival calculus for determination of the necessity of periodontal treatment.

Effects of butyrate on the erythropoietin receptor of cell line IW201

The murine erythroleukemic cell line, IW201, normally expresses only low-affinity erythropoietin receptors. Exposure of these cells for 48 hours to sodium butyrate results in a change in receptor kd from about 600 pmol/L to 100 to 200 pmol/L. This change in affinity is accompanied by downregulation of both receptor number and receptor mRNA. Cells exposed to sodium butyrate for 2 hours show a similar change in kd but no change in receptor number. The butyrate effect on kd at 2 hours is abrogated by either cycloheximide or actinomycin D. These data indicate that an accessory protein induced by sodium butyrate is responsible for high-affinity binding of erythropoietin.

Stimulation of chloride secretion by P1 purinoceptor agonists in cystic fibrosis phenotype airway epithelial cell line CFPEo-

1. P1 purinoceptor agonists like adenosine have been shown to stimulate Cl- transport in secretory epithelia. In the present study, we investigated whether P1 agonist-induced Cl- secretion is preserved in cystic fibrosis airway epithelium and which signalling mechanism is involved. The effects of purinoceptor agonists on Cl- secretion were examined in a transformed cystic fibrosis airway phenotype epithelial cell line, CFPEo-. 2. Addition of adenosine (ADO; 0.1-1 mM) markedly increased 125I efflux rate. The rank order of potency of purinoceptor agonists in stimulating 125I efflux was ADO > AMP > ADP approximately equal to ATP. A similar order of potency was seen in transformed cystic fibrosis nasal polyp cells, CFNPEo- (ADO > ATP > AMP > ADP). These results are consistent with the activation of Cl- secretion via a P1 purinoceptor. 3. The P1 agonists tested (at 0.01 and 0.1 mM) revealed a rank order of potency of 5'-N-ethylcarboxamine adenosine (NECA) > 2-chloro-adenosine (2-Cl-ADO) > R-phenylisopropyl adenosine (R-PIA). 4. The known potent A2 adenosine receptor (A2AR) agonist, 5'-(N-cyclopropyl) carboxamidoadenosine (CPCA, 2 microM) but not the A1 adenosine receptor agonist, N6-phenyl adenosine (N6-phenyl ADO, 10 microM) markedly increased 125I efflux rate (baseline, 5.9 +/- 2.0% min-1, + CPCA, 10.9 +/- 0.6% min-1; P < 0.01). The stimulant effect of CPCA (10 microM) was abolished by addition of the A2AR antagonist 3,7-dimethyl-1-propargylxanthine (DMPX) (100 microM; reported K(i) = 11 +/- 3 microM). These results favour the involvement of A2AR. 5. ADO (0.1-mM) and CPCA (2 microM) both induced a marked increase in intracellular [Ca2+] ([Ca2+]i); the effect of the latter was again abolished by pretreatment of the cells with DMPX. By contrast, N6-phenyl ADO did not affect [Ca2+]i. 6. In patch-clamp experiments, ADO (1 mM) induced an outwardly-rectified whole-cell Cl- current (baseline, 2.5 +/- 0.8 pA pF-1, + ADO, 78.4 +/- 23.8 pA pF-1; P < 0.02), which was largely inhibited in cells internally perfused with a selective inhibitory peptide of the multifunctional Ca2+/calmodulin-dependent protein kinase, CaMK [273-302] (20 microM), as compared to a control peptide, CaMK [284-302]. Addition of BAPTA (10 mM), a Ca2+ chelator, to the perfusion pipette also abolished the ADO-elicited Cl- current. 7. In conclusion, our results suggest that A2AR participates in regulation of airway C1 secretion via aCa2+-dependent signalling pathway, which involves CaMK and appears to be at least partially conserved in cystic fibrosis airway epithelial cells.

Activation of intestinal CFTR Cl- channel by heat-stable enterotoxin and guanylin via cAMP-dependent protein kinase

Heat-stable enterotoxins (STa) produced by pathogenic bacteria induce profound salt and water secretion in the gut, leading to diarrhea. Recently, guanylin, an endogenous peptide with properties similar to STa, was identified. While STa and guanylin bind to the same receptor guanylyl cyclase and raise cell cGMP, the signaling mechanism distal to cGMP remains controversial. Here we show that STa, guanylin and cGMP each activate intestinal Cl- secretion, and that this is abolished by inhibitors of cAMP-dependent protein kinase (PKA), suggesting that PKA is a major mediator of this effect. These agents induce Cl- secretion only in cells expressing the wild-type CFTR, indicating that this molecule is the final common effector of the signaling pathway. The involvement of CFTR suggests a possible cystic fibrosis heterozygote advantage against STa-induced diarrhea.

Hemin or butyrate increases constitutive erythropoietin formation by mouse erythroleukemia cell lines

The murine erythroleukemic cell lines NN10 and IW32 secrete erythropoietin (Epo) constitutively. Although both cell lines have Epo receptors (Epo-R), they do not respond to external Epo to undergo erythroid differentiation. In both cell lines, hemoglobin synthesis can be induced by hemin or butyrate. We report here on the effects of these two inducers on Epo production by the same cell lines. Both hemin and butyrate caused a three- to five-fold increase in Epo secretion on a percell basis. The effects were dose- and time-dependent, as was found previously for hemoglobin synthesis. The mechanism of the effect on Epo secretion is posttranscriptional, since the steady-state level of Epo mRNA was not altered by the inducers.