Analysis of pathological complete response rates with paclitaxel-based regimens in trimodality therapy for esophageal cancer.

The study aimed to examine whether omission of 5-fluorouracil (5-FU)-containing chemotherapy alters pathological complete response rates in patients receiving trimodality therapy for locally advanced esophageal cancer. A total of 159 patients were identified. One hundred twenty-nine patients received platinum/5-FU concurrently with radiotherapy, and 30 received taxane/platinum-containing chemoradiotherapy prior to esophagectomy. Patients were staged using the 2002 American Joint Committee on Cancer staging system. Patients were matched between chemotherapeutic groups, with no significant demographic or clinical differences other than T stage (14% T2 in the 5-FU group; no T2 in the platinum/taxane group) and radiotherapy technique (8.5% received intensity-modulated radiotherapy in the 5-FU group; 60% in the platinum/taxane group). Pathological complete response rates for 5-FU and platinum/taxane-based groups were not significantly different (45% and 30%, respectively; P = 0.1548). Five-year overall survival and progression-free survival were not statistically different between the two groups. Significant predictors of pathological complete response included N stage (56% N0 and 33% N1; P = 0.0083), histology (37% adenocarcinoma and 59% squamous cell; P = 0.0123), tumor location (39% distal and 59% proximal/mid; P = 0.048), gastroesophageal junction involvement (33% involved and 55% uninvolved; P = 0.005), and radiotherapy end-to-surgery interval (50% < 55 days and 34% ≥ 55 days; P = 0.04). Grades 3-4 hematological toxicity was higher in the 5-FU group (36%) than in the paclitaxel-containing therapy group (17%; P = 0.0484). Use of paclitaxel-containing chemoradiotherapy did not result in inferior pathological complete response, overall survival, or progression-free survival rates, and resulted in less hematological toxicity than 5-FU treatment.

Involvement of cAMP-response element binding protein in corticotropin-releasing factor (CRF)-induced down-regulation of CRF receptor 1 gene expression in rat anterior pituitary cells.

Corticotropin-releasing factor (CRF) is a major secretagogue of adrenocorticotopic hormone from the anterior pituitary and a key activator of the hypothalamic-pituitary-adrenal axis. We previously reported that CRF down-regulates expression of the CRF type-1 receptor (CRF-R1) mRNA in cultured rat anterior pituitary cells. The present study was conducted to clarify the signal transduction systems involved in CRF-induced down-regulation of CRF-R1 gene expression in the anterior pituitary. Northern blot analysis revealed that, under serum-free conditions, 10 nM CRF decreased CRF-R1 mRNA levels in cultured rat anterior pituitary cells as we reported previously. Treatment with 5 mM 8-Br-cAMP reduced CRF-R1 mRNA levels within 2 h. The mRNA level fell to 37+/-3% of the basal level at 2 h and remained low for 16 h after treatment. This CRF-induced reduction of CRF-R1 mRNA expression was inhibited completely by pretreatment with protein kinase A (PKA) inhibitor (1 microM H-89). Further examination revealed that after pretreatment with 10 microM of antisense oligodeoxynucleotide for cyclic AMP-response element binding protein (CREB), the CRF-induced inhibition of CRF-R1 mRNA was partially decreased to 79+/-4% of the control level 2 h after administration of CRF. These findings indicate that CRF may down-regulate CRF-R1 mRNA expression via a cAMP-PKA-mediated mechanism in rat anterior pituitary cells, and that CREB may mediate at least a portion of this inhibitory effect.

Effect of D-glucose on nitric oxide release from glomerular endothelial cells.

BACKGROUND: Altered glomerular production of nitric oxide (NO) may be involved in hyperfiltration in early diabetic nephropathy. However little is known as to the role of glomerular endothelial cells (GECs) in diabetic hyperfiltration and their ability to release NO in response to hyperglycemia. METHODS: Using an established cell line, we directly monitored NO release from GECs in response to various concentrations of D-glucose, D-mannitol, and L-arginine, an NO synthase (NOS) agonist. L-Arginine-induced NO release was examined in the cells pretreated for different periods up to 24 h with 10 or 30 mM D-glucose. We also measured serially the accumulation of nitrite, the stable metabolite of NO, produced by the cells incubated for up to 24 h under 10 or 30 mM D-glucose conditions in the presence or absence of the NOS inhibitor, L-NAME. RESULTS: Direct measurement of NO demonstrated that D-glucose, but not D-mannitol, stimulation resulted in a rapid and dose-dependent increase in NO release by the cells. However, L-arginine-induced NO release was attenuated significantly in the cells preincubated for more than 12 h with 30 mM D-glucose compared to 10 mM D-glucose. The L-NAME-inhibitable production of nitrite in the media was significantly increased 1.5--2.0-fold until 6 h after incubation with 30 mM D-glucose compared to 10 mM D-glucose. CONCLUSIONS: We conclude that D-glucose, but not D-mannitol, produces a rapid and dose-dependent increase in NO release, whereas exposure to high D-glucose for more than 12 h may blunt NOS activity and/or NO stability in the GECs. These observations may therefore be important for glomerular endothelial dysfunction induced by hyperglycemia that is still tentative and may have a role in diabetic nephropathy.

Coronary vasodilation and positive inotropism by urocortin in the isolated rat heart.

Corticotropin-releasing factor (CRF) has a coronary vasodilator effect and a positive inotropic effect on the isolated rat heart. Recently, expression of CRF receptor type 2 (CRF-R2) has been demonstrated in the heart. In addition, urocortin (Ucn), a new member of the CRF family, has been reported to have much greater affinity for CRF-R2 than CRF. It is suggested that the cardiac effects of Ucn may be more potent than those of CRF. We compared the effect of Ucn with that of CRF on isolated rat heart. The effects of Ucn were then analyzed to determine whether these effects were mediated by CRF receptors and/or any other mediators under the following conditions: perfusion buffer containing (1) alpha-helical CRF 9-41, (2) indomethacin, (3) N(G)-nitro-l -arginine methylester and (4) propranolol. Ucn exhibited a greater effect with a longer duration of action than CRF. Indomethacin significantly attenuated the vasodilator effects of Ucn (P<0.05). CRF receptor antagonist diminished both coronary vasodilation and the positive inotropic effects of Ucn (P<0.05). These results suggest that the cardiac effects of Ucn may be mediated by a CRF receptor, and prostaglandins may be involved in the vasodilator effect.

Involvement of phosphorylation of beta-subunit in cAMP-dependent activation of L-type Ca2+ channel in aortic smooth muscle-derived A7r5 cells.

We investigated the effect of intracellular cAMP on the gating kinetics of L-type Ca2+ channel in an A7r5 smooth muscle-derived cell line using the whole-cell patch-clamp technique. Application of dibutyryl cyclic AMP (db-cAMP) to the cell increased the magnitude of Ca2+ currents through L-type Ca2+ channels (I(Ca)), and shifted the current-voltage relationship (I-V curve) for I(Ca) to the left. The magnitudes of maximum I(Ca) were 14.1 +/- 0.7 before and 16.0 +/- 1.1 pA/pF after application of 1 mM db-cAMP (P < 0.05). The values of the half-activation potential (V(1/2)) of I(Ca), estimated from activation curves, were -7.0 +/- 0.8 mV before and -10.8 +/- 1.0 mV after application of db-cAMP (P < 0.05). In cells pretreated with 10 microM Rp-cAMPS (a specific inhibitor of PKA), db-cAMP affected neither the I-V curve nor the activation curve for I(Ca). In cells pretreated with the antisense oligonucleotide for the beta-subunit of L-type Ca2+ channel, db-cAMP failed to enhance I(Ca) or alter the activation curve. On the other hand, in the cells pretreated with the nonsense oligonucleotide, application of db-cAMP caused an increase in magnitude of I(Ca) and shifted the activation curve to the left. Western blot analysis revealed that the pretreatment of cells with antisense oligonucleotide but nonsense oligonucleotide reduced the expression of the beta-subunit of the L-type Ca2+ channel. We conclude that the cAMP-dependent phosphorylation of the beta-subunit potentiates the voltage dependency of the activation kinetics of the L-type Ca2+ channel in A7r5 cells.

A case of acromegaly accompanied by adrenal preclinical Cushing's syndrome.

We encountered a 58-year-old woman with acromegaly accompanied by a cortisol-secreting adrenal tumor without clinical features of hypercortisolism. The simultaneous occurrence of these two endocrinopathies in one individual is extremely rare. She was diagnosed as having diabetes mellitus 8 years ago. Afterwards, in spite of insulin therapy, her hyperglycemia could not be well controlled. Her acromegaly and preclinical Cushing's syndrome were histopathologically proven to be due to a pituitary adenoma and an adrenocortical adenoma, respectively. Successful treatment for these endocrinopathies resulted in greatly improved blood sugar control because of a reduction in insulin resistance. In this case of preclinical Cushing's syndrome, replacement therapy with glucocorticoid was able to be discontinued at only 8 weeks after adrenalectomy, so that the period of necessary replacement was much shorter than that for overt Cushing's syndrome. This is the first report describing insulin resistance before and after treatment in a case of acromegaly accompanied by adrenal preclinical Cushing's syndrome.

Bactericidal effect of electrolyzed neutral water on bacteria isolated from infected root canals.

OBJECTIVE: The purposes of this study were to examine the time-related changes in pH, oxidation-reduction potential, and concentration of chlorine of electrolyzed neutral water and to evaluate the bactericidal effect of electrolyzed neutral water against bacteria from infected root canals. STUDY DESIGN: Various properties of electrolyzed neutral water--pH value, oxidation-reduction potential, and concentration of chlorine--were measured at different times after storage of the water in the open state, the closed state, or the closed-and-dark state. The bactericidal effect of the various electrolyzed neutral water samples was then tested against 17 strains of bacteria, including 15 strains isolated from infected canals, as well as against 1 strain of fungus. Each bacterial or fungal suspension was mixed with electrolyzed neutral water, and the 2 substances were reacted together for 1 minute. After incubation for 1 to 7 days, the bactericidal effect of the electrolyzed neutral water was determined. RESULTS: The pH value and oxidation-reduction potential of electrolyzed neutral water remained almost unchanged when the water was stored in a dark, closed container. However, the concentration of chlorine decreased from 18.4 ppm to 10.6 ppm. Electrolyzed neutral water showed a bactericidal or growth-inhibitory effect against the bacteria. CONCLUSIONS: The results indicate that electrolyzed neutral water maintains a constant pH and oxidation-reduction potential when kept in a closed container without light and that it exhibits a bacteriostatic/bactericidal action against isolates obtained from infected root canals.

The genomic organization of the human corticotropin-releasing factor type-1 receptor.

We determined the genomic organization of human CRF type-1 receptor (hCRF-R1). The gene coding for hCRF-R1 consists of at least 14 exons and spans over 20 kilobases. hCRF-R1's three reported isoforms originate from the same gene by alternative splicing. The first hCRF-R1, which binds to CRF with the highest affinity and transduces the most sensitive cAMP accumulation in response to CRF, is encoded in a total of 13 exons, the only one excluded being exon 6. The second isoform contains an additional 29-amino acid sequence which corresponds to exon 6. Unlike the first isoform, the third lacks a 40-amino acid sequence, corresponding to exon 3. Exon-intron boundaries are the same as that of the consensus sequence. Locations of introns in the coding sequence are similar to human CRF-R1, rat CRF-R1, human CRF-R2alpha and others belonging to the human glucagon receptor family.

A hypopituitary patient who attained tall stature without growth hormone.

We describe an unusual patient with hypopituitarism who attained tall stature even without growth hormone (GH). A 37-year-old man was devoid of secondary sexual characteristics, but manifested tall stature with a eunuchoidal feature. Serum levels of GH, insulin-like growth factor-I, gonadotropins and testosterone were all below normal. GH secretion was not enhanced by any provocative stimulus. Adrenocorticotropic hormone increased after administration of corticotropin releasing hormone, but not after insulin-induced hypoglycemia. Thyrotropin increased in response to thyrotropin releasing hormone, but both free T3 and T4 did not rise. Magnetic resonance imaging disclosed a transected pituitary stalk. The present patient had hypopituitarism due to perinatal problems but had grown with the aid of non-GH growth-promoting factors, which suggests that man may be able to achieve statural growth even without GH.

Saireito (a Chinese herbal drug) decreases inhibitory effect of prednisolone and accelerates the recovery of rat hypothalamic-pituitary-adrenal axis.

Saireito, a saiko agent (a Chinese herbal drug), increases the synthesis and secretion of ACTH by stimulating hypothalamic CRH release. In the present study, we examined the effect of food containing saireito (1.5%) on the recovery of the hypothalamic-pituitary-adrenal axis after treating male rats with prednisolone (PSL, 200 microM) in drinking water for 14 days. Saireito was administered during and after PSL administration. The rats were decapitated at various times after PSL administration. Tail-pinch stress had been applied to some rats. The plasma ACTH response to tail-pinch stress in the PSL + saireito group recovered to the control level on day 1, but that in the group given PSL alone recovered on day 3. The ACTH level in the anterior pituitary and the CRH level in the median eminence of the PSL + saireito group returned to the control level on day 3, and that in the group given PSL alone returned to it on day 5. These results indicate that the administration of saireito reduces the negative feedback effect of PSL on the hypothalamus and pituitary and accelerates the recovery of the hypothalamic CRH and pituitary ACTH level after glucocorticoid treatment.

Serotonin stimulates corticotropin-releasing factor gene expression in the hypothalamic paraventricular nucleus of conscious rats.

To examine the direct effects of serotonin (5-HT) on the release and synthesis of corticotropin-releasing factor (CRF) in the hypothalamic paraventricular nucleus (PVN), 5-HT was microinjected just onto the bilateral PVN of conscious rats. Plasma adrenocorticotropic hormone (ACTH) levels peaked at 30 min and returned to the basal levels in 90 min. Northern blot analysis revealed that the CRF messenger RNA (mRNA) level in the PVN as well as the proopiomelanocortin mRNA level in the anterior pituitary significantly increased 120 min after the 5-HT injections (50-250 nmol/side). Pretreatment with intracerebroventricular (i.c.v.) injection of pindobind 5-HT1A (5 nmol) or LY-278584 (500 nmol) completely abolished the 5-HT-induced ACTH response, whereas LY-53857 (100 nmol) was without effect. These results suggest that 5-HT stimulates CRF release, which has interactions with 5-HT1A and 5-HT3 receptors on CRF neurons in the PVN, and activates CRF synthesis in conscious rats.

[Sexual and gonadal dysfunction in adrenal disorders].

Among various diseases of the adrenals, major disorders that cause sexual and gonadal disturbances are congenital adrenal hyperplasia(CAH) and Cushing's syndrome, and the others include virilizing or feminizing adrenocortical tumors. CAH was reviewed based on the recent advances in molecular genetics. The most striking discovery was steroidogenic acute regulatory protein, mutations of which produce lipoid adrenal hyperplasia that was previously attributed to P-450scc deficiency. Reversible amenorrhea or impotence is found in patients with Cushing's syndrome. Low plasma estrogen and testosterone levels are associated with female and male patients, respectively. Elevated adrenal androgen accounts for mild virilization in female patients with ACTH-dependent subtypes. The sites of action at which hypercortisolemia suppresses the hypothalamic-pituitary-gonadal axis were discussed.

Safety and kinetic properties of a humanized antibody to human interleukin-6 receptor in healthy non-human primates.

A monoclonal antibody, hPM-1, was constructed by grafting the complementarity determining regions to human interleukin-6 (IL-6) receptor, raised in mouse, onto a human antibody backbone (humanized antibody). It is expected to be useful as a therapeutic agent for IL-6-related diseases such as multiple myeloma. To investigate the toxicological and kinetic properties of hPM-1 preliminarily, normal cynomolgus monkeys, which showed cross-reactivity with hPM-1, were intravenously administered with hPM-1 at doses of 0 (vehicle), 4 or 40 mg/kg once a week for 13 weeks. Upon toxicological examination, there were no changes in clinical signs, food consumption, body weights, urinalyses, body temperatures, electrocardiograms, hematological and biochemical parameters including blood platelet counts, serum levels of immunoglobulin G and C-reactive protein, and pathological findings. In a kinetic study, serum concentrations of hPM-1 showed a linearity between doses of 4 and 40 mg/kg. The serum concentrations, even at a dose of 4 mg/kg, were maintained at a high enough level to inhibit the IL-6 functions throughout the period of the study. Concentrations of hPM-1 in bone marrow were almost equal to those in serum. The antibodies against hPM-1 were detected only in one of four monkeys receiving hPM-1. This study suggests that blockage of the IL-6 receptor by hPM-1 does not induce any influence on a healthy living body, and hPM-1 is not toxic under the conditions of this investigation.

Corticotropin-releasing factor up-regulates its own receptor gene expression in corticotropic adenoma cells in vitro.

To investigate the expression of CRF receptor (CRF-R) in human corticotropic adenoma (hCA) cells, we analyzed messenger RNA (mRNA) levels of type-1 CRF-R (CRF-R1). Adenomas were obtained from 10 patients with Cushing's disease. Northern blot analysis using a rat CRF-R1 complementary RNA probe revealed a main hybridization band of 2.7 kilobases in all the hCAs. The CRF-R1 mRNA level significantly increased after 1 h, reached 15-fold the basal level at 8 h, and remained elevated 24 h after the addition of 10 nmol/L CRF in vitro. Dose dependency of the stimulatory effect of CRF was also demonstrated in hCA cells, whereas CRF down-regulated CRF-R1 mRNA levels in rat anterior pituitary (AP) cells. Treatment with dexamethasone or vasopressin decreased the CRF-R1 mRNA level in hCA cells, as observed in rat AP cells. In conclusion, we detected CRF-R1 mRNA in all hCAs tested. The CRF-R1 mRNA level was up-regulated by CRF itself in cultured hCA cells, in contrast to the down-regulation in rat AP cells.