Differential expression of decorin and biglycan genes during palatogenesis in normal and retinoic acid-treated mice.

Proteoglycans are involved in secondary palate formation. In the present study, we focused on two small leucine-rich proteoglycans, decorin and biglycan, because they assembled extracellular matrix molecules such as collagens and modulated signaling pathway of transforming growth factor-beta. To investigate the functions of decorin and biglycan in palatogenesis, we compared their mRNA expression patterns between normal palate and retinoic acid-induced cleft palate in mice by using in situ hybridization analysis during the period of embryonic day 13.5 (E13.5) to E15.5. On E13.5, decorin mRNA was expressed in the epithelia and mesenchyme on the nasal side of the developing secondary palate. During the period the palate shelves were fusing (E14.5), decorin mRNA was strongly expressed in the mesenchyme but its expression pattern was asymmetric; decorin mRNA expression area in the nasal side was broader than that in the oral side. The expression of decorin mRNA was hardly detected in the mesenchyme on either side of the medial edge epithelium. After fusion (E15.5), its expression converged to the mesenchyme just around the palatine bone. Biglycan mRNA was ubiquitously distributed throughout the palatal mesenchyme for the mid-gestation period. Its expression area became limited to the ossification area within the palate after the late gestation period. In the retinoic acid-treated mice, the area of the decorin gene expression expanded to the core region of the palate primordium where little signal was observed in control mice. On the other hand, biglycan in the retinoic acid-treated mice did not show remarkable change in its distribution patterns compared with that in the control mice. These findings suggest that decorin and biglycan play distinct roles in palatogenesis, and decorin was more actively involved in the process of secondary palate formation than biglycan. Up-regulation of decorin gene expression in the retinoic acid-treated mice might influence the pathogenesis of cleft palate.     

Electro-acupuncture stimulation effects on duodenal motility in anesthetized rats

The effect of electro-acupuncture stimulation (EAS) on duodenal motility was examined in anesthetized, artificially ventilated rats. EAS was applied to the abdominal area or to a hindpaw for 30 s at stimulus intensities of 0.1-10.0 mA with a stimulus frequency of 20 Hz. The duodenal motility was measured using the balloon method at a position about 1.5 cm caudal from the pylorus. Duodenal motility was inhibited by EAS at intensities of more than 5.0 mA (suprathreshold of group IV afferent excitation) when applied to the abdominal area. The duodenal inhibitory response existed after bilateral vagotomy or spinal transection, but was abolished by sectioning bilateral splanchnic nerves. Duodenal motility was facilitated by EAS at intensities of more than 2.0 mA (subthreshold of group IV, and suprathreshold for groups II+III afferent excitation) when applied to a hindpaw. The duodenal facilitatory response by EAS to a hindpaw existed after sectioning the splanchnic nerves, but disappeared after bilateral vagotomy or spinal transection. Furthermore, repetitive electrical stimulation of vagal efferent nerves enhanced duodenal motility, while repetitive electrical stimulation of the splanchnic efferent nerves inhibited the motility. It was concluded that the inhibitory response of duodenal motility elicited by EAS to the abdominal area is a spinal reflex response involving splanchnic inhibitory efferent nerves, and the enhanced response of duodenal motility by EAS to a hindpaw is a supraspinal reflex response involving vagal excitatory nerves.     

Control of B cell production by the adaptor protein lnk. Definition Of a conserved family of signal-modulating proteins

Lnk is an SH2 domain-containing adaptor protein expressed preferentially in lymphocytes. To illuminate the importance of Lnk, we generated lnk(-/-) mice. Whereas T cell development was unaffected, pre-B and immature B cells accumulated in the spleens. In the bone marrow, B-lineage cells were proportionately increased, reflecting enhanced production of pro-B cells that resulted in part from hypersensitivity of precursors to SCF, the ligand for c-kit. Hence, Lnk ordinarily acts to regulate B cell production. Further characterization of lnk(-/-) mice also revealed that full-length Lnk is a 68 kDa protein containing a conserved proline-rich region and a PH domain. Lnk is a representative of a multigene adaptor protein family whose members act, by analogy with Lnk, to modulate intracellular signaling.     

Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile

Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.     

Boy with a chromosome del (3)(q12q23) and Blepharophimosis syndrome

We report on a 6-year-old boy with de novo 46, XY, del(3)(q12q23) and bilateral blepharo-phimosis, ptosis, epicanthus inversus, in addition to multiple other anomalies. Since 4 previously reported cases of interstitial deletion of 3q involving 3q23 band are clinically similar, we propose this blepharophimosis sequence due to 3q23 deletion as a further “contiguous gene syndrome”.     

Frequent cellular senescence in small bile ducts in primary biliary cirrhosis: a possible role in bile duct loss

The pathogenesis of progressive bile duct loss in primary biliary cirrhosis remains unclear. In this study, the involvement of cellular senescence of biliary epithelial cells was examined in liver tissue samples from patients with primary biliary cirrhosis (n = 33), and compared with control diseased and normal livers (n = 83). In addition, cellular senescence was induced by oxidative stress in cultured mouse biliary epithelial cells. Biliary epithelial cells in small bile ducts in primary biliary cirrhosis, especially those in patients presenting with chronic non-suppurative cholangitis, frequently expressed senescence-associated beta-galactosidase, and senescence-associated p16(INK4) and p21(WAF1/CIP). In contrast, senescence-associated markers were rarely expressed in small bile ducts in control livers. The infiltration of myeloperoxidase-positive inflammatory cells into biliary epithelial cell layers was closely associated with the cellular senescence of biliary epithelial cells in early-stage PBC. Cellular senescence of cultured mouse biliary epithelial cells was induced by treatment with H2O2 via the p38MAPK-dependent pathway and nitric oxide-augmented H2O2-induced cellular senescence. Oxidative stress- and nitric oxide-mediated cellular senescence may be involved in bile duct lesions, which are followed by progressive bile duct loss in primary biliary cirrhosis.     

Viability and osteogenic potential of cryopreserved human bone marrow-derived mesenchymal cells

Human bone marrow-derived mesenchymal cells contain mesenchymal stem cells (MSCs), which are well known for their osteo/chondrogenic potential and can be used for bone reconstruction. This article reports the viability of cryopreserved human mesenchymal cells and a comparison of the osteogenic potential between noncryopreserved and cryopreserved human mesenchymal cells with MSC-like characteristics, derived from the bone marrow of 28 subjects. The viability of cryopreserved mesenchymal cells was approximately 90% regardless of the storage term (0.3 to 37 months). It is clear by fluorescence-activated cell sorter analysis that the cell surface antigens of both noncryopreserved and cryopreserved mesenchymal cells were negative for hematopoietic cell markers such as CD14, CD34, CD45, and HLA-DR but positive for mesenchymal characteristics such as CD29 and CD105. To monitor the osteogenic potential of the cells, such as alkaline phosphatase (ALP) activity and in vitro mineralization, a subculture was conducted in the presence of dexamethasone, ascorbic acid, and glycerophosphate. No difference in osteogenic potential was found between cells with or without cryopreservation treatment. In addition, cells undergoing long-term cryopreservation (about 3 years) maintained high osteogenic potential. In conclusion, cryopreserved as well as noncryopreserved human mesenchymal cells could be applied for bone regeneration in orthopedics.     

Involvement of cAMP response element-binding protein activation in salivary secretion.

OBJECTIVE: Saliva secretion is mediated by cAMP and the calcium signaling pathway in salivary acinar cells. The PKA signaling pathway plays an important role in protein secretion through the activation of cAMP, in fluid secretion through the elevation of intracellular calcium and in the activation of cAMP response element-binding protein (CREB), which is involved in these signaling cascades. In this study, we investigated whether the activation of CREB plays a part in the salivary secretion in mice. METHODS: We examined CREB activation by assessing phosphorylation at the serine-133 position using Western blotting. RESULTS: Carbachol (a muscarinic acetylcholine agonist) and isoproterenol (a beta-adrenergic agonist) markedly activated CREB in parotid acinar cells. Carbachol and isoproterenol-induced CREB phosphorylation was blocked by atropine (a muscarinic acetylcholine antagonist) and propranolol (a beta-adrenergic antagonist), respectively. The PKA inhibitor H89 inhibited CREB activation, but the PLC inhibitor U73122 did not. Moreover, carbachol- and isoproterenol-stimulated amylase secretion from parotid acinar cells was inhibited by H89 and adenoviral dominant-negative CREB. CONCLUSION: These results indicate that the muscarinic and beta-adrenergic activation of CREB was mediated through the PKA pathway and that CREB is involved in protein secretion from parotid acinar cells.     

Increase in O(2) delivery with hyperoxia does not increase O(2) uptake in tetanically contracting dog muscle

We investigated the influence of hyperoxia on O(2) uptake in tetanically contracting canine gastrocnemius. Hyperoxia showed neither increase in O(2) uptake nor decrease in lactate release, irrespective of increased O(2) supply, venous Po(2) and vascular resistance, as compared to normoxia, suggesting that hyperoxia decreases O(2) diffusion conductance and/or effective O(2) supply probably due to arteriovenous O(2) diffusion shunt.