Simultaneous treatment of PVC and oyster-shell wastes by mechanochemical means.

This work presents a new process for dechlorinating poly-vinyl chloride (PVC) by the use of oyster-shell waste. The process consists of milling of PVC waste with oyster-shell waste, followed by washing the milled sample with water. The milling of PVC and oyster-shell mixture results in size reduction and rupture in bonds, leading to mechanically induced reactions between the two to form CaCl2 and hydrocarbon with C=C bonds. Washing the milled mixtures with water at room temperature allows complete removal of chlorine from the milled sample. More than 95% of chlorine in PVC was removed when 2h grinding is conducted for the mixture. The present process could offer a potential route to the handling and disposal of oyster-shell and PVC wastes.

Cuticle network and orientation preference of photonic crystals in the scales of the weevil Lamprocyphus augustus.

This paper reports the structural and optical investigations of the structural colour of the weevil Lamprocyphusaugustus The photonic crystal structure within the weevil's scales was investigated using sequential focused ion-beam milling and scanning electron microscopy imaging. We carefully analysed the reconstructed three-dimensional structure to determine the unit cell of the photonic crystal. It was found that the cuticle network of the cubic unit cell perfectly matches the previously reported diamond-based network. However, different results were obtained for the crystal orientations of the small crystal domains that comprise the entire photonic crystal structure in the scales: <111> directions are highly preferred along the surface normal of the scale. This finding explains the fact that the scale is almost uniformly coloured despite the multi-domain structure. It is confirmed experimentally and theoretically that the wavelength range of the reflection band corresponds to the gap of the photonic band.

Identification of cell-type-specific mutations in nodal T-cell lymphomas.

Recent genetic analysis has identified frequent mutations in ten-eleven translocation 2 (TET2), DNA methyltransferase 3A (DNMT3A), isocitrate dehydrogenase 2 (IDH2) and ras homolog family member A (RHOA) in nodal T-cell lymphomas, including angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma, not otherwise specified. We examined the distribution of mutations in these subtypes of mature T-/natural killer cell neoplasms to determine their clonal architecture. Targeted sequencing was performed for 71 genes in tumor-derived DNA of 87 cases. The mutations were then analyzed in a programmed death-1 (PD1)-positive population enriched with tumor cells and CD20-positive B cells purified by laser microdissection from 19 cases. TET2 and DNMT3A mutations were identified in both the PD1+ cells and the CD20+ cells in 15/16 and 4/7 cases, respectively. All the RHOA and IDH2 mutations were confined to the PD1+ cells, indicating that some, including RHOA and IDH2 mutations, being specific events in tumor cells. Notably, we found that all NOTCH1 mutations were detected only in the CD20+ cells. In conclusion, we identified both B- as well as T-cell-specific mutations, and mutations common to both T and B cells. These findings indicate the expansion of a clone after multistep and multilineal acquisition of gene mutations.

Cross talk of dual-signal transduction systems in the regulation of DNA synthesis by parathyroid hormone in osteoblastic osteosarcoma cells.

There has been recent evidence that calcium/protein kinase C (Ca/PKC) messenger system as well as adenylate cyclase are involved in the signal transduction stimulated by PTH. We therefore examined the role of these dual-signal transduction systems and the interaction of these systems in the regulation of DNA synthesis by PTH in the osteoblastic osteosarcoma cells, UMR-106. As recently reported, 10(-4) M Sp-cAMPS, a direct activator of cAMP-dependent protein kinase (PKA), and 10(-4) M dibutyryl-cAMP, as well as hPTH-(1-34), caused the significant inhibition of [3H]thymidine incorporation (TdR). Both A23187 and ionomycin (10(-8)-10(-6) M) inhibited TdR in a dose-dependent manner, with a minimal effective dose at 10(-7) M. Although 10(-6) M phorbol 12-myristate 13-acetate (PMA) caused slight but significant stimulation of TdR by itself, it augmented not only dibutyryl-cAMP- but also Sp-cAMPS-induced inhibition of TdR. On the other hand, 4 alpha-phorbol 12,13-didecanoate, incapable of activating PKC, failed to augment these cAMP analogs-induced effects. Pretreatment with 50 microM H-7, an inhibitor of PKC, not only abolished the PMA-induced augmentation of effect by cAMP analogs but also significantly blocked the PTH-induced inhibitory effect on TdR. Pretreatment with 10(-6) M PMA, which downregulates PKC, significantly inhibited the PTH-induced suppression of TdR. Combined treatment with cAMP analog (dibutyryl-cAMP or Sp-cAMPS) and calcium ionophore (A23187 or ionomycin) caused additive effects on TdR, and PMA used in combination with both cAMP analog and calcium ionophore induced the further inhibition of TdR.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction of parathyroid hormone-related peptide-responsive dual signal transduction systems in osteoblastic osteosarcoma cells: role in PTHrP-induced homologous desensitization.

In osteoblastic UMR-106 cells, 10(-7) M human (h) PTH-related peptide (PTHrP)-(1-34) significantly induced the formation of total inositol phosphates to the same degree as 10(-7) M hPTH-(1-34), confirming that in addition to cAMP-dependent protein kinase (PKA), PTHrP possesses another signal transduction system, calcium/protein kinase C (Ca/PKC). Experiments were therefore performed to characterize the cross talk of these dual-signal transduction systems and its participation in the PTHrP-induced homologous desensitization of cAMP and cytosolic calcium (Cai) response in osteoblasts. Preincubation with 10(-7) M hPTHrP-(1-34) caused homologous desensitization, resulting in a remarkable decrease in cAMP accumulation in response to further exposure to PTHrP. This effect was significant after 2 h pretreament and reached a maximum at 6 h. Pretreatment with the PKC-activating phorbol ester phorbol 12-myristate-13-acetate (PMA, 10(-6) M) for 30 minutes and 6 h caused a significant increase and decrease in cAMP responsiveness to PTHrP, respectively. Pretreatment with calcium ionophores (A23187 or ionomycin, 10(-6) M), not for 30 minutes but for 6 h, caused a significant decrease in cAMP responsiveness to PTHrP. H-7 (an inhibitor of PKC, 50 microM) significantly blocked not only PMA- but also PTHrP-induced desensitization of the cAMP response. PTHrP caused the complete homologous desensitization of an increase in Cai within 30 minutes. Pretreatment with dibutyryl-cAMP (10(-4) M) for 30 minutes caused significant inhibition of the PTHrP-induced increase in Cai, and pretreatment with Sp-cAMPS (10(-4) M), a direct activator of PKA, for 30 minutes completely blocked the PTHrP-induced increase in Cai.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of high calcium concentration on the functions and interactions of osteoblastic cells and monocytes and on the formation of osteoclast-like cells.

The present study was performed to clarify the role of high calcium concentration and the appearance of mononuclear cells at the resorptive site in bone remodeling. Our recent study revealed that the high concentration of extracellular calcium ([Ca2+]e) stimulated DNA synthesis in osteoblastic MC3T3-E1 cells not only directly but also indirectly via monocytes. Human monocyte-conditioned medium (CM) significantly stimulated DNA synthesis and inhibited alkaline phosphatase (ALP) activity. In contrast, when monocytes were cultured at high [Ca2+]e concentrations (more than 3 mM), CM from these monocytes significantly stimulated ALP activity in MC3T3-E1 cells. Such stimulatory effect of CM was not observed at a high magnesium concentration (Mg2+, 5 mM). Treatment of monocytes with the calcium ionophore A23187 did not affect the CM-induced effect on DNA synthesis and ALP activity in these cells. To determine the migration potency of MC3T3-E1 cells and monocytes toward the high [Ca2+]e, chemotaxis assay was performed. The increasing [Ca2+]e (more than 3 mM) induced a chemotactic response of MC3T3-E1 cells as well as monocytes, but the high concentration of Mg2+ (5 mM) did not induce it. On the other hand, treatment with high [Ca2+]e (more than 3 mM) or CM significantly inhibited the 1,25-(OH)2D3-induced formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNC) from their precursors derived from mouse spleen cells.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized, double-blinded comparison of Thymoglobulin versus Atgam for induction immunosuppressive therapy in adult renal transplant recipients.

BACKGROUND: The aim of this study was to compare the efficacy and safety of Thymoglobulin (a rabbit-derived polyclonal antibody) to Atgam (a horse-derived polyclonal antibody) for induction in adult renal transplant recipients. METHODS: Transplant recipients (n=72) were randomized 2:1 in a double-blinded fashion to receive Thymoglobulin (n=48) at 1.5 mg/kg intravenously or Atgam (n=24) at 15 mg/kg intravenously, intraoperatively, then daily for at least 6 days. Recipients were observed for at least 1 year of follow-up. RESULTS: By 1 year after transplantation, 4% of Thymoglobulin-treated patients experienced acute rejection compared with 25% of Atgam-treated patients (P=0.014). The rate of acute rejection was lower with Thymoglobulin than Atgam (relative risk=0.09; P=0.009). Rejection was less severe with Thymoglobulin than Atgam (P=0.02). No recurrent rejection occurred with Thymoglobulin compared with 33% with Atgam (P=NS). Patient survival was not different, but the composite end point of freedom from death, graft loss, or rejection, the "event-free survival," was superior with Thymoglobulin (94%) compared with Atgam (63%; P=0.0005). Fewer adverse events occurred with Thymoglobulin (P=0.013). Leukopenia was more common with Thymoglobulin than Atgam (56% vs. 4%; P<0.0001) during induction. The mean absolute lymphocyte count remained below baseline with Thymoglobulin throughout the study (P<0.007), but with Atgam, significant lymphocyte reductions occurred only at day 7. The incidence of cytomegalovirus disease was less with Thymoglobulin than Atgam at 6 months (10% vs. 33%; P=0.025). CONCLUSIONS: Brief (7-day) induction with Thymoglobulin resulted in less frequent and less severe rejection, a better event-free survival, less cytomegalovirus disease, fewer serious adverse events, but more frequent early leukopenia than induction with Atgam. These results may in fact be explained by a more profound and durable beneficial lymphopenia.

Effects of 22-oxacalcitriol on bone metabolism in vitro: comparison with calcitriol--effects of 22-oxacalcitriol on osteoclast-like cell formation and bone-resorbing activity.

22-Oxacalcitriol (OCT), a synthetic vitamin D3 analog, can mimic the ability of calcitriol to differentiate leukemia and skin cells, to enhance the immune response and to suppress parathyroid hormone secretion, but has much less calcemic activity than that of calcitriol. The mechanism of this selective action remains not fully understood, and the actions of OCT on bone metabolism are little known. The present study was, therefore, designed to investigate the effects of OCT and calcitriol on: the proliferation and functions of osteoblastic MC3T3-E1 cells; osteoclast-like cell formation from hemopoietic blast cells in the absence of stromal cells as well as from unfractionated bone cells in the presence of stromal cells; bone resorption; and the proliferation of MC3T3-E1 cells via monocytes. 22-Oxacalcitriol and calcitriol inhibited [3H]thymidine (TdR) incorporation, alkaline phosphatase activity and collagen synthesis of MC3T3-E1 cells to a similar degree. Both OCT (10(-10)-10(-8) mol/l) and calcitriol significantly and similarly stimulated osteoclast-like cell formation from both hemopoietic blast cells and unfractionated bone cells. 22-Oxacalcitriol (10(-10) and 10(-8) mol/l) significantly stimulated bone resorption, although to a slightly lesser degree than did calcitriol. Human monocyte-conditioned medium (CM) significantly stimulated TdR incorporation into MC3T3-E1 cells. On the other hand, CM obtained from monocytes treated with calcitriol (10(-10)-10(-8) mol/l) significantly inhibited TdR incorporation in a dose-related fashion, whereas CM obtained from monocytes treated with OCT (10(-10)-10(-8) mol/l) significantly stimulated TdR incorporation in a dose-related fashion.(ABSTRACT TRUNCATED AT 250 WORDS)

Sensitization following Thymoglobulin and Atgam rejection therapy as determined with a rapid enzyme-linked immunosorbent assay. US Thymoglobulin Multi-Center Study Group.

Monoclonal and polyclonal anti-thymocyte preparations play an important role in solid organ transplant immunosuppression. While it is generally accepted that blocking anti-idiotypic antibodies can decrease the efficacy of retreatment with mouse monoclonal antibody preparations, sensitization levels and subsequent effects on treatment efficacy are less clear for polyclonal preparations. Serum samples were obtained from 148 patients participating in a multicentre, double-blind randomized phase III trial comparing Atgam (Pharmacia Upjohn, horse anti-thymocyte globulin) with Thymoglobulin (SangStat Medical Corporation, rabbit anti-thymocyte globulin). Recipients of a first or second renal allograft undergoing biopsy proven acute rejection were randomized to treatment with Atgam or Thymoglobulin. Serum samples were analysed for presence of anti-thymoglobulin and anti-Atgam antibodies. Sensitization levels to rabbit IgG in Thymoglobulin-treated patients (68%, n = 54) was similar to sensitization to horse IgG in Atgam-treated patients (78%, n = 54) (two-sided p value = 0.4, Fisher's exact test), although Atgam-treated patients remained sensitized longer (at day 90, 67% anti-horse IgG positive in Atgam treated vs 24% anti-rabbit IgG in Thymoglobulin positive, p = 0.001). No difference was seen in the production of a crossreactive response. Similarly, sensitization had no significant effect on treatment success or failure. For Thymoglobulin-treated patients, the sensitization rate in successfully treated patients was 68%, while inpatients with treatment failures it was 71% (p = not significant, ns). In Atgam-treated patients, the sensitization rate in successfully treated patients was 82%, while in patients with treatment failures it was 67% (p = ns). In conclusion, patients treated with Thymoglobulin and patients treated with Atgam exhibited similar levels of sensitization, presensitization and crossreactive sensitization, although the anti-horse response was longer lasting; neither presensitization nor treatment-induced sensitization appeared to effect treatment efficacy.

Effect of retinoic acid on the proliferation and alkaline phosphatase activity of osteoblastic MC3T3-E1 cells by modulating the release of local regulators from monocytes.

There has been some evidence suggesting an important role of mononuclear cells at bone remodeling sites in the coupling of bone formation to bone resorption. Since cells of the monocyte-macrophage lineage produce important local regulators of bone remodeling, we examined effects of human monocytes-conditioned medium (CM) treated with retinoic acid on [3H] thymidine incorporation (TdR) and alkaline phosphatase (ALP) activity of osteoblastic MC3T3-E1 cells. Treatment of MC3T3-E1 cells with retinoic acid (10(-8) to 10(-6) M) caused an inhibition of TdR in a dose-dependent manner and an inhibition of ALP activity at 10(-6) M. Conditioned medium from monocytes untreated with retinoic acid caused a stimulation of TdR and an inhibition of ALP activity in these cells. In contrast, treatment of monocytes with retinoic acid (10(-8) or 10(-6) M) abolished both stimulation of DNA synthesis and inhibition of ALP activity induced by CM. The present study suggested that retinoic acid modulated osteoblast proliferation and ALP activity not only directly but also indirectly, presumably through modulating the release of local regulators as to bone remodeling from monocytes.

Isolation and cultivation of porcine hepatocytes for extracorporeal artificial liver support system.

OBJECTIVE: To develop procedures for the successful harvesting of large quantities of viable and functional pig liver cells from abattoir organs. METHODS: The procedure included partial liver lobe retrograde perfusion and mechanical/enzymatic digestion of the liver tissue, followed by separation of the hepatocytes, based on size and density, from contaminating cell types. RESULTS: Digestion of the partial liver lobe resulted in an average yield of 1.39 x 10(9) cells (9.9 x 10(8) cells/g liver) with an average viability of 92.5%. The yield and viability of cells were improved by dispase/collagenase resultant digestion. The emergence of blebby cells was blocked by supplying oxygen to the cell isolation buffers. Isolated hepatocytes seeded onto polystyrene surfaces remained viable and functional at a level comparable to that of rat hepatocytes, although their function decreased over time. CONCLUSIONS: Adult pig hepatocytes can be harvested with high yields and retain viability and differentiated function using this method. Abattoir pig livers can be an excellent source of hepatocytes for use as the biological component of artificial liver assist devices.

Percutaneous transhepatic cholecystoscopy and biliary endoscopic lithotripsy.

We have been developing procedures for percutaneous transhepatic cholecystoscopy (PTCCS) through the sinus tract of percutaneous transhepatic cholecystostomy since 1981, and have used this method on 67 patients with gall bladder diseases. We also performed biliary endoscopic lithotripsy with PTCCS and percutaneous transhepatic cholangioscopy (PTCS) using a Nd-YAG laser or electrohydraulic shock wave lithotripter to non-operatively treat 83 patients with cholangiolithiasis, 11 with cholecystolithiasis, and four with cholecysto-choledocholithiasis. The present paper reports the PTCCS procedures and their usefulness for the precise diagnosis of early carcinoma of the gall bladder, and the usefulness and safety of biliary endoscopic lithotripsy techniques.