TCTP as a therapeutic target in melanoma treatment.

BACKGROUND: Translationally controlled tumour protein (TCTP) is an antiapoptotic protein highly conserved through phylogeny. Translationally controlled tumour protein overexpression was detected in several tumour types. Silencing TCTP was shown to induce tumour reversion. There is a reciprocal repression between TCTP and P53. Sertraline interacts with TCTP and decreases its cellular levels. METHODS: We evaluate the role of TCTP in melanoma using sertraline and siRNA. Cell viability, migration, and clonogenicity were assessed in human and murine melanoma cells in vitro. Sertraline was evaluated in a murine melanoma model and was compared with dacarbazine, a major chemotherapeutic agent used in melanoma treatment. RESULTS: Inhibition of TCTP levels decreases melanoma cell viability, migration, clonogenicity, and in vivo tumour growth. Human melanoma cells treated with sertraline show diminished migration properties and capacity to form colonies. Sertraline was effective in inhibiting tumour growth in a murine melanoma model; its effect was stronger when compared with dacarbazine. CONCLUSIONS: Altogether, these results indicate that sertraline could be effective against melanoma and TCTP can be a target for melanoma therapy.

Correlation of circulating betatrophin concentrations with insulin secretion capacity, evaluated by glucagon stimulation tests.

AIM: To investigate the relationship between plasma betatrophin concentrations and insulin secretion capacity in people with Type 2 diabetes. METHODS: Glucagon stimulation tests (1 mg) were performed in 70 people with Type 2 diabetes after an overnight fast. Plasma betatrophin concentrations were measured using an enzyme-linked immunosorbent assay. Insulin secretion capacity was evaluated by measuring increments of C-peptide concentration in response to glucagon stimulation, and creatinine clearance was determined by comparing creatinine concentrations in serum and 24-h urine samples. RESULTS: Plasma betatrophin concentrations were positively correlated with duration of Type 2 diabetes (r = 0.34, P = 0.003), and negatively correlated with increments of C-peptide concentration (r = 0.37, P = 0.001) and creatinine clearance (r = 0.37, P = 0.001). The correlation with increments of C-peptide concentration remained significant after adjustment for age and duration of Type 2 diabetes (r = 0.25, P = 0.037). Multivariate analysis identified age and increments of C-peptide concentration as independent factors associated with plasma betatrophin levels. CONCLUSION: Plasma betatrophin levels inversely correlate with insulin secretion capacity, suggesting that betatrophin levels are regulated by insulin secretion capacity in humans.

Accelerated neutrophil apoptosis in mice lacking A1-a, a subtype of the bcl-2-related A1 gene.

To elucidate the role of A1, a new member of the Bcl-2 family of apoptosis regulators active in hematopoietic cell apoptosis, we established mice lacking A1-a, a subtype of the A1 gene in mice (A1-a-/- mice). Spontaneous apoptosis of peripheral blood neutrophils of A1-a-/- mice was enhanced compared with that of either wild-type mice or heterozygous mutants (A1-a+/- mice). Neutrophil apoptosis inhibition induced by lipopolysaccharide treatment in vitro or transendothelial migration in vivo observed in wild-type mice was abolished in both A1-a-/- and A1-a+/- animals. On the other hand, the extent of tumor necrosis factor alpha-induced acceleration of neutrophil apoptosis did not differ among A1-a-/-, A1-a+/-, and wild-type mice. The descending order of A1 mRNA expression was wild-type, A1-a+/-, and A1-a-/-. Taken together, these results suggest that A1 is involved in inhibition of certain types of neutrophil apoptosis.

Exendin-4 protects pancreatic beta cells from the cytotoxic effect of rapamycin by inhibiting JNK and p38 phosphorylation.

It has been reported that the immunosuppressant rapamycin decreases the viability of pancreatic beta cells. In contrast, exendin-4, an analogue of glucagon-like peptide-1, has been found to inhibit beta cell death and to increase beta cell mass. We investigated the effects of exendin-4 on the cytotoxic effect of rapamycin in beta cells. Incubation with 10 nM rapamycin induced cell death in 12 h in murine beta cell line MIN6 cells and Wistar rat islets, but not when coincubated with 10 nM exendin-4. Rapamycin was found to increase phosphorylation of c-Jun amino-terminal kinase (JNK) and p38 in 30 minutes in MIN6 cells and Wistar rat islets while exendin-4 decreased their phosphorylation. Akt and extracellular signal-regulated kinase (ERK) were not involved in the cytoprotective effect of exendin-4. These results indicate that exendin-4 may exert its protective effect against rapamycin-induced cell death in pancreatic beta cells by inhibiting JNK and p38 signaling.

[Impacts of aortic valve replacement on cardiac function in patients with aortic stenosis].

To prevent patient-prosthesis mismatch (PPM) after aortic valve replacement (AVR), we set up our original standard criteria for the selection of the size of the prosthetic valve. We also routinely perform supra-annular enlargement in patients with small aortic annuli. The objective of this study was to assess the impact of our procedure on the postoperative cardiac function of patients suffering from aortic stenosis (AS). We retrospectively reviewed 102 consecutive surgical patients with AS from 1999 to 2004. The patients were classified into the following 3 groups based on the sizes of their prosthesis (group S : 19 mm prosthesis, n = 34; group M : 21 mm prosthesis, n = 51; and group L : > 23 mm prosthesis, n = 17). Cardiac function was evaluated using echocardiography preoperatively, immediately postoperatively, and 6 months after the operation. There were no hospital deaths during the study period. A favorable hemodynamic outcome of all 3 groups was achieved. Our surgical strategy for AS was thought to be useful to prevent PPM after AVR.

[Advantage of supra-annular patch enlargement in aortic stenosis with a small aortic annulus].

BACKGROUND: We routinely perform supra-annular patch enlargement as a strategy to avoid patient-prosthesis mismatch (PPM) in patients with a small aortic annulus who are undergoing aortic valve replacement (AVR). METHOD: We performed a retrospective review of 128 consecutive single AVR patients from 1999 to 2005. Of these, 34 patients underwent supra-annular patch enlargement. The enlargement was selectively performed in patients at risk of PPM. This involved patch extension of the aortotomy just above the annulus of noncoronary sinus, and valve implantation with stitches placed directly on the patch. Along with this procedure, AVR with a valve size appropriate to body surface area (BSA) was performed. RESULT: Of these patients, 74% were female and the mean BSA was less than 1.50 m2. The enlargement required an average of 33 minutes of additional aortic clamp time. The 30-day mortality was 0%. A favorable hemodynamic outcome was achieved. CONCLUSION: Our results show that supra-annular patch enlargement can be performed with minimal added risk, relative to standard root enlargement and a satisfactory hemodynamic status can be achieved by employing this procedure.

[Segmental mitral suture annuloplasty combined with resection--suture technique for posterior leaflet prolapse].

A segmental mitral suture annuloplasty technique is consisted of double-layer sutures anchored in the fibrous trigone on the valve repair side and along the annulus to the midpoint of the posterior leaflet. This suture technique is an alternative of Paneth Burr method using only one-side of the procedure. We recommend this technique especially in cases of mitral regurgitation which can be repaired by a simple resection-suture technique for posterior leaflet, and not in cases of severe annular dilatation, rheumatic, or ischemic diseases. We have examined this technique in 40 cases over the last 8 years and the results showed no recurrence of the mitral regurgitation.

Effect of low-intensity training on transient kinetics of pulmonary oxygen uptake during moderate-intensity cycle exercise.

AIM: It is unclear whether the slowed time constant of phase II in pulmonary oxygen uptake on-kinetics (V̇O2τ) in unfit and inactive men would be shortened by low exercise intensity (low-intensity) walking training. We therefore tested the hypothesis that the slowed V̇O2τ in sedentary population would speed up due to low-intensity walking training with high volume. METHODS: Ten unfit and inactive male subjects (aged 26 to 50 yrs) underwent a low-intensity (30-40% of V̇O2max), long-duration (>60 min) training in the form of walking exercise 3-4 times a week for 12 weeks. We prospectively collected data on anthropometric, maximal oxygen uptake (V̇O2max), time constant of heart rate (HRτ) and V̇O2τ before training (0 wk; Pre) and every six weeks (6 wk; Mid, 12 wk; Post) from the beginning of the training. RESULTS: Anthropometric variables and V̇O2max showed no significant changes throughout the training program, whereas HRτ showed a tendency to be shortened with a progress of the training with no significant change. The slowed V̇O2τ at Pre (47.6±5.6 s) remained almost unchanged at Mid (48.8±4.9 s), but had a significant decrease at Post (40.5±7.9 s, P<0.05). CONCLUSION: In this study acceleration of the slowed V̇O2τ due to low-intensity walking training is thought to occur presumably owing to an improved matching of oxygen delivery to oxygen utilization at the site of gas exchange in active muscle tissue. We concluded that low-intensity walking training at beginning stage of training could contribute to the acceleration of the slowed V̇O2τ in unfit and inactive subjects.

Nifedipine-induced gingival hyperplasia: a clinical and in vitro study.

Two cases of gingival hyperplasia associated with long-term administration of nifedipine, a drug that dilates coronary arteries, are reported. The clinical and histopathological features of the gingival hyperplasia induced by nifedipine were similar to those induced by phenytoin, an anticonvulsant drug. In the present cases, gingival inflammation had developed before drug administration. In one case, extensive dental plaque control in addition to surgical removal of the overgrown gingival tissues resulted in satisfactory progress without the need to discontinue drug administration, suggesting that the preexisting gingival inflammation was involved in the development of this periodontal disease. In the other case, change from nifedipine to another drug resulted in spontaneous recovery, strongly suggesting that the drug had induced the gingival hyperplasia. Nifedipine had no direct effects in vitro on proliferation or collagen synthesis of gingival fibroblastic cells from one of the patients. Study of these two cases suggests that both local inflammatory factors and long-term administration of nifedipine were responsible for the gingival hyperplastic changes observed.

Actions of parathyroid hormone on cultured human dental pulp cells.

The responsiveness of human dental pulp (HDP) cells to parathyroid hormone (PTH) was investigated by measuring their cyclic AMP (cAMP) content, DNA synthesis, alkaline phosphatase activity, collagen synthesis, and glycosaminoglycan (GAG) synthesis. PTH dose-dependently increased the intracellular cAMP 1 min after the addition of PTH. Confluent HDP cells on day 14 expressed a high level of cAMP production after addition of 3 units/ml PTH. The hormone did not affect DNA synthesis by HDP cells. Alkaline phosphatase activity was suppressed by PTH to 81% of control (p < 0.01), and addition of dibutyryl cAMP to the medium mimicked the effect of PTH (79% of control, p < 0.01). The hormone inhibited collagen synthesis (15% decrease of [3H] proline incorporation, p < 0.01), and stimulated non-collagen protein synthesis (10% increase, p < 0.05). The increase of non-collagen protein by PTH was in accordance with the enhancement of GAG synthesis (17% increase of [35S]sulfate incorporation, p < 0.01). Dibutyryl cAMP caused further increase of GAG synthesis, to 155% of control (p < 0.01). Observations of the radiolabeled proteins on 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis after metabolic labeling with [14C]proline and [35S]sulfate revealed a similar tendency to the quantitative determinations in which PTH inhibited collagen synthesis and stimulated GAG synthesis. These findings suggest that HDP cells have some osteoblastic characteristics in terms of PTH responsiveness, and that this culture system is a useful model for studies of human dental pulp.

Regulation of glycosaminoglycan synthesis by parathyroid hormone and prostaglandin E2 in cultured dental pulp cells.

The effects of parathyroid hormone (PTH) and prostaglandin E2 (PGE2) on glycosaminoglycan (GAG) synthesis in bovine dental pulp cells were studied. Dibutyryl cyclic adenosine 3',5'-monophosphate and isobutyl methylxanthine were used to assess whether their effects were mediated by intracellular cAMP. Glycosaminoglycan synthesis was assayed by measuring [35S]sulfate incorporation into the GAG fraction of dental pulp cells. Glycosaminoglycan synthesis was increased 1.3-fold by PTH (4 units per ml) alone, 1.6-fold by PTH in the presence of isobutyl methylxanthine, 1.2-fold by PGE2 (100 ng per ml) alone, and 1.5-fold by PGE2 in the presence of isobutyl methylxanthine. Dibutyryl cyclic adenosine 3',5'-monophosphate enhanced GAG synthesis in a concentration-dependent manner and mimicked the effects of PTH and PGE2. The effects of these hormones on pulp and gingival cells were compared; addition of PTH, PGE2, and dibutyryl cAMP had no effect on gingival cell GAG synthesis, whereas their addition induced significant increases of GAG in pulp cells. These results indicate that PTH and PGE2 are involved in the differentiation of dental pulp cells and that these effects are mediated by cAMP.

Effects of parathyroid hormone, 1,25-dihydroxyvitamin D3, and prostaglandin E2 on alkaline phosphatase activity in cultured dental pulp and gingiva cells of bovine calf.

The effects of parathyroid hormone (PTH), 1,25-dihydroxyvitamin D3, and prostaglandin E2 (PGE2) on alkaline phosphatase activity on cultured dental pulp and gingiva cells of bovine calf were compared. In pulp cells, PTH, 1,25-dihydroxyvitamin D3, and PGE2 significantly increased alkaline phosphatase activity, but no increase in the enzyme activity by these factors was observed in gingiva cells. Dibutyryl cAMP also increased alkaline phosphatase activity in both types of cell, but the increase in pulp cells was greater than that in gingiva cells. Treatment of the cultured pulp cells with PTH or PGE2 significantly increased the intracellular cAMP content. These results suggest that calciotropic factors such as PTH, 1,25-dihydroxyvitamin D3, and PGE2 may be involved in the differentiation of dental pulp cells and that some of these effects (those of PTH and PGE2) are mediated by cAMP.

Manure phosphorus extractability as affected by aluminum- and iron by-products and aerobic composting.

Shifts in manure phosphorus (P) chemical forms and pool sizes induced by water treatment residuals and industrial mineral by-products are largely undefined. We conducted a manure P fractionation study to determine mechanisms of reduction of dissolved reactive phosphorus (DRP) in poultry manure upon mineral by-product additions. The effects of composting on the P immobilization efficacy of the by-products were determined using laboratory self-heating composting simulators. The mineral by-products included an aluminum-water treatment residual (Al-WTR) and an iron-rich titanium-processing by-product. The noncomposted manure averaged 0.11 g g(-1) of total P as DRP forms. The by-products significantly reduced manure DRP, by an average of 39 and 48% in the Al- and the Fe-treated manure, respectively. The by-products also reduced the 0.5 M NH4F-extractable phosphorus (FEP) fraction. Shifts in P forms between FEP and 0.1 M NaOH-extractable phosphorus (SHEP) depended upon the Al and Fe contents of the by-products while the combined FEP + SHEP pool remained constant. Phosphate sorption measurements supported the observations that the Fe-rich by-product was more effective at reducing manure DRP and enhancing the formation of SHEP forms at the expense of FEP than the Al-WTR. Composting had no effect on the efficacy of either by-product to reduce DRP. Potential mechanisms of enhanced P stabilization in treated manure upon composting included chemical shifts from the DRP and FEP fractions to the citrate-bicarbonate-dithionite extractable P fraction. Thus, the choice of P immobilization agents affected the stability of immobilized P forms and should be taken into consideration in developing manure processing and nutrient stabilization methods.

[Traumatic diaphragmatic herniation after continuous thoracic drainage: a case report].

We report a case of traumatic diaphragmatic hernia (TDH) resulting from continuous thoracic drainage and was successfully treated by surgical procedures. A 45-year-old man was admitted to our department due to shock after a blunt trauma by a traffic accident. As he revealed left hemothorax on admission, continuous thoracic drainage was performed. Soon after the drainage, diaphragmatic hernia occurred as an incarceration of the spleen into the thoracic cavity. In the literature, 80 cases with TDH have been reported in Japan since 1986. The purpose of this study is to discuss the mechanism of TDH in the acute phase and to consider its appropriate diagnostic tools. The following two results were obtained. (1) TDH may be appeared during the clinical course, especially after a continuous thoracic drainage, in patients with damaged diaphragm by blunt traumas. (2) CT is the most effective tool for the diagnosis of TDH.