Strain-rate effect on the biomechanical response of bovine temporomandibular joint disk under compression

This study evaluates the effect of strain rate on the biomechanical responses of bovine temporomandibular joint (TMJ) disk under compression. Ten specimens derived from the central region of bovine TMJ disks were used for compression tests. Each specimen was loaded upto 20% of strain with seven different strain rates: 1, 10, 20, 30, 40, 50, and 60%/s. Although the stress-strain curves presented similar patterns for all the specimens, the strain-rate effect was obvious. The linear modulus by regression fit for the linear part of the curve was significantly larger at 60%/s of strain rate than at the lower strain rates. The "supplemental stress" ratio (SSR) obviously increased with the augmentation of the strain rate. At strain rates of 30-60%/s, the SSR was significantly larger than those at strain rates below 20%/s. These findings indicate that although water easily can move through the TMJ disk at the lower strain rates, the higher strain rates make such movement difficult. It is concluded that the secondary changes of the TMJ disk may be dependent on the pattern and velocity of masticatory mandibular movements directly associated with the dynamic strain rate in the TMJ disk.     

Rapid and efficient generation of lentivirally gene-modified dendritic cells from DC progenitors with bone marrow stromal cells

Since dendritic cells (DC) play pivotal roles in both innate and adaptive immunity, DC can be a good target for immuno-gene therapy. However, the optimal generation method for gene-modified DC has not yet been well exploited. CD34+ cells from cord blood (CB), bone marrow (BM), or peripheral blood (PB) were expanded in a medium containing stem cell factor (SCF), flt 3 ligand (Flt3L) and thrombopoietin (TPO) with or without HESS-5, a murine BM stromal cell line, for 2 weeks (the first expansion step), then differentiated to DC in a medium containing granulocyte-macrophage colony-stimulating factor (GM-CSF), flt 3 ligand (Flt3L), stem cell factor (SCF), tumor necrosis factor-alpha (TNF-alpha), IL-4, and lipopolysaccharide (LPS) for 9 days (the second differentiation step). DC progenitors were transduced with human immunodeficiency virus (HIV) vectors at different time points during the second step. Use of HESS-5 during the first step resulted in more DC generation than without it (cell expansion: CB, 10,461 vs. 354-fold; BM, 962 vs. 225-fold; peripheral blood mononuclear cell (PBMC), 8,506 vs. 240-fold; %DC: CB, 83.4% vs. 76.9%; BM, 83.6 vs. 69.8%; PBMC, 85.9 vs. 60.5%). Gene transduction to the in vitro expanded DC progenitors at day 3 during the second step, resulted in better final yield of the gene-modified DC than that to those at day 0 or day 6 (as much as 44% of DC expressed green fluorescence protein (GFP) as a transgene) and the transduction efficiency correlated with endocytic ability and percent of S phase. DC transduced with an HIV vector encoding a melanoma antigen, MART-1, were adequately recognized by specific anti-MART-1 CTL. The two-step culture method with HESS-5 is useful for rapid expansion of DC progenitors and subsequent lentiviral gene transduction to DC.     

Peripheral blood mononuclear cells stimulate progesterone production by luteal cells derived from pregnant and non-pregnant women: possible involvement of interleukin-4 and interleukin-10 in corpus luteum function and differentiation

Human luteal cells have been reported to express human leukocyteantigen-DR and lymphocyte functional antigen-3 on the cell surface,suggesting physiological interaction between luteal cells andT-lymphocytes through the menstrual cycle into early pregnancy.To elucidate the role of peripheral lymphocytes on corpus luteumdifferentiation, the effect of peripheral blood mononuclearcells (PBMC) on steroidogenesis by luteal cells was investigated.The production of Th-2 cytokines such as interleukin (IL)-4and IL-10 by the co-cultured cells was also examined, and theeffects of these cytokines on progesterone production by lutealcells were investigated. Corpora lutea were obtained from eightnon-pregnant women in the luteal phase and five women in earlypregnancy for luteal cell culture. PBMC were isolated from unrelatedwomen in the follicular phase, secretory phase, and early pregnancy.After co-culture with allogenic PBMC for 48 h, progesteroneproduction was significantly enhanced by PBMC from the secretoryphase and early pregnancy in the non-pregnant luteal cell culture.In the pregnant luteal cell culture, a significant increasein progesterone production was also observed by the co-culturewith PBMC from women in early pregnancy, showing that PBMC havea luteotrophic effect. The stimulatory effects of PBMC werealso observed in co-culture conditions which prevented directcell-to-cell interaction with luteal cells, showing the minorinfluence of mixed lymphocyte reaction. By co-culture with PBMC,the production of IL-10, but not IL-4, was significantly augmentedin luteal cell culture derived from non-pregnant women, whereasthe production of both IL-4 and IL-10 was significantly enhancedin the luteal cell culture derived from pregnant women. Moreover,IL-4 and IL-10 promoted progesterone production by culturedluteal cells, especially in the luteal cell culture derivedfrom corpora lutea of early pregnancy. These findings indicatethat PBMC stimulate progesterone production by luteal cellsand suggest the involvement of PBMC in corpus luteum functionand differentiation probably via the Th-2-type lymphocytes.     

Restriction fragment length polymorphisms of the CYP11B1 gene in the Japanese population

Summary Restriction fragment length polymorphisms (RFLPs) of the CYP11B1 gene were studied in Japanese using cDNA clone P450c11 as a probe. Genomic DNAs from 60 unrelated Japanese individuals were digested with 8 different restriction enzymes and analyzed by Southern blot hybridization. Two RFLPs were detected inMspI digests of the DNA. One(A) was characterized by polymorphic bands at 3.4 and 2.5 kilobasepairs (kb) and the other (B) by polymorphic bands at 1.7 and 1.2 kb. The third RFLP was observed inPvuII-digested samples and was polymorphic at 5.8 and 4.0 kb bands. Two of the three RFLPs found, RFLP (A) and (C), have not been described in the only previous report which was based on Caucasian samples. We also examined the RFLPs of a 3 generation family of 11-hydroxylase deficiency caused by an abnormality of the CYP11B1 gene. All the family members were homozygous in all three RFLPs and was thus not informative.     

Intercellular adhesion molecule-1 in patients with idiopathic interstitial pneumonia

This study focuses on a possible role of intercellular adhesion molecule-1 (ICAM-1) in interstitial pulmonary diseases. We determined a soluble form of ICAM-1 in serum and bronchoalveolar lavage fluid (BALF) using ELISA in patients with usual interstitial pneumonia (UIP), bronchiolitis obliterance organizing pneumonia (BOOP), or nonspecific interstitial pneumonia (NSIP). In addition, we investigated the expression of ICAM-1 in the lung tissues of these patients by means of immunohistochemical staining. Serum levels of soluble ICAM-1 were significantly higher in patients with UIP or NSIP than in healthy subjects, and were also high in patients with BOOP. The soluble ICAM-1 in BALF tended to be higher in patients with UIP, BOOP, or NSIP than in normal subjects. A significant correlation was seen between soluble levels of ICAM-1 in serum and BALF. In the immunostaining of ICAM-1 of the lung tissues, ICAM-1 expression was more pronounced in patients with UIP than in those with BOOP or NSIP. The increased expression of ICAM-1 was seen in type II alveolar epithelium and vascular endothelium in patients with interstitial pneumonia. A positive correlation was observed between the degree of ICAM-1 expression in the lung tissues and the BALF levels of soluble ICAM-1. The expression of ICAM-1 in type II alveolar epithelium suggests that ICAM-1 plays a specific role in the fibrotic process of the lung, and that the measurement of soluble ICAM-1 in sera and BALF could be a useful marker for evaluating the progression of fibrosis.     

Biological activities of Bacteroides forsythus lipoproteins and their possible pathological roles in periodontal disease

Bacteroides forsythus is a gram-negative, anaerobic, fusiform bacterium and is considered to be an etiological agent in periodontal disease. A lipoprotein fraction prepared from B. forsythus cells by Triton X-114 phase separation (BfLP) activated human gingival fibroblasts and a human monocytic cell line, THP-1, to induce interleukin-6 production and tumor necrosis factor alpha production. BfLP was found to be capable of inducing nuclear factor-kappaB translocation in human gingival fibroblasts and THP-1 cells. By using Chinese hamster ovary K1 cells transfected with Toll-like receptor genes together with a nuclear factor-kappaB-dependent CD25 reporter plasmid, it was found that signaling by BfLP was mediated by Toll-like receptor 2 but not by CD14 or Toll-like receptor 4. BfLP induced apoptotic cell death in human gingival fibroblasts, KB cells (an oral epithelial cell line), HL-60 cells (a human myeloid leukemia cell line), and THP-1 cells but not in MOLT4 cells (a T-cell leukemia cell line). Caspase-8, an initiator caspase in apoptosis, was found to be activated in these cells in response to BfLP stimulation. Thus, this study suggested that BfLP plays some etiological roles in oral infections, especially periodontal disease, by induction of cell activation or apoptosis.     

Specificity of co-promoting effects of caffeine on thyroid carcinogenesis in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine

The specificity of copromotion effects of caffeine with known goitrogenic factors on thyroid carcinogenesis was examined in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine (DHPN). Male F344 rats were divided into 8 groups, each consisting of 10 animals, and received a single sc injection of 2,800 mg/kg DHPN. From one week after the DHPN initiation, they were given basal diet, iodine deficiency (ID) diet, 500 ppm phenobarbital (PB) solution or 1,000 ppm sulfadimethoxine (SDM) solution with or without 1,500 ppm caffeine feeding for 12 weeks. The caffeine, PB, SDM, and ID treatments significantly (p < 0.05 or 0.01) increased the relative thyroid weights, and the increases with PB or ID were further (p < 0.05 or 0.01) enhanced in combination with caffeine. SDM drastically promoted thyroid carcinogenesis in association with increased serum TSH levels regardless of the caffeine treatment. Thyroid follicular carcinomas and adenomas were more frequently observed in the additional caffeine groups than in the ID alone groups. The incidence and multiplicity of focal thyroid follicular hyperplasias in the ID-treated groups were significantly (p < 0.05 and 0.01) elevated in the case of combination with caffeine. Increases in serum TSH levels with PB or ID were also further enhanced in combination with caffeine. Serum thyroid hormone levels were significantly (p < 0.01) decreased by SDM but significantly (p < 0.05 or 0.01) increased by caffeine, PB or ID. Our results clearly indicate that dietary caffeine at a high dose of 1,500 ppm interacts with ID, but neither SDM nor PB, to promote rat thyroid carcinogenesis although the combined caffeine + PB treatment somewhat affected thyroid weights as well as thyroid hormone levels.     

The UDP-galactose translocator gene is mapped to band Xp11.23-p11.22 containing the Wiskott-Aldrich syndrome locus

We have cloned a segment of the human gene encoding UDP-galactose translocator by genetic complementation of its defective mutant in mouse FM3A cells. Chromosome mapping using fluorescentin situ hybridization revealed that the cloned gene hybridized to the Xp11.23-11.23 region of the X chromosome. This region is shared by the locus of Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency disorder, characterized by defective sugar chains on cell surface components. Genetic and phenotypic similarities suggest a possible link between UDP-galactose translocator and the Wiskott-Aldrich syndrome (WAS).