Cardiac and hemodynamic effects of TZC-5665, a novel pyridazinone derivative, and its metabolite in humans and dogs

1. TZC-5665 is a novel pyridazinone derivative with vasodilatory and beta-adrenergic blocking activities and type III phosphodiesterase inhibitory action. 2. In healthy volunteers, TZC-5665 was rapidly absorbed and immediately metabolized. Its main metabolite, M-2, remained at a higher concentration in plasma. Orally administered TZC-5665 reduced end-diastolic left ventricular volume (20.16 ml) and exhibited a tendency to increase ejection fraction (0.04). 3. In dogs, M-2 dose-dependently increased cardiac contractility and reduced both preload and afterload. These effects appeared more potent in the failed heart than in the normal heart. At the same dose (30 micrograms/kg), the effects of M-2 seem to be more potent than those of milrinone. 4. We concluded that TZC-5665 is a useful medication for treating patients with chronic congestive heart failure (CHF) because of the positive inotropic and vasodilating effects due to its active metabolite in addition to its own beta-adrenergic blocking actions.

[Reconstructive surgery for head and neck cancers under multiple facility cooperation system]

The problems with the system for reconstructive surgery for head and neck cancers in our department where plastic surgeons are regularly invited from distant facilities were discussed. Especially, the importance of preoperative discussion between the plastic surgeons and ENT doctors was stressed. The computer system with Internet will play an important role in exchanging information such as CT scans and MRI scans between the plastic surgeons and ENT doctors. Moreover, the establishment of a system to prevent postoperative troubles such as closure of anastomosed vessels was stressed. Twenty-seven re-vascularized free flaps had been transferred with a 96.3% success rate (26 of 27 cases). We concluded that the system for reconstructive surgery under the multiple facility cooperation system worked well.

Effects on antitumor activity and cytokine production in the thoracic cavity by intrapleural administration of Lactobacillus casei in tumor-bearing mice

The effects Lactobacillus casei YIT9108 (LC 9018) on antitumor activity and cytokine production in Meth A fibrosarcoma (Meth A)-bearing BALB/c mice were examined. Intrapleural (i.pl.) administration of LC 9018 was effective in prolonging the survival of Meth A-bearing mice, and frequently cured mice of the tumor. However, the results also indicated that the effect of LC 9018 was in part inhibited in mice treated with anti-CD3 or anti-CD8 antibody, but not affected in anti-CD4 antibody-treated mice. In contrast, LC 9018 had little effect on Meth A-bearing SCID or nude mice. These results demonstrated that CD8+ T cells participated in prolonging the survival of Meth A-bearing mice. Moreover, the examination of the production of several cytokines revealed that the production of interferon-gamma and interleukin-6 was, in particular, augmented in the exudated fluid of the thoracic cavity in BALB/c mice injected with LC 9018 i.pl. These results suggested that i.pl. administration of LC 9018 induced those cytokines which had the potential to activate the thoracic macrophages or proliferate the thoracic lymphocytes to the cytotoxic T cells. Taken together, these findings demonstrated that the prolonging effects on survival by i.pl. administration of LC 9018 depended on CD8+ T cells, and the i.pl. administration of LC 9018 into i.pl. Meth A-bearing mice induced several cytokines which participated in the subsequent immunoresponses.

Determination of absolute configuration and biological activity of new immunosuppressants, mycestericins D, E, F and G

Mycestericins D, E, F and G were isolated from the culture broth of Mycelia sterilia ATCC 20349 as potent immunosuppressants. Mycestericins F and G were identical with dihydromycestericins D and E, respectively. Their absolute configurations were determined by use of the modified MOSHER'S method and by comparison of the CD spectra of their benzoate derivatives with those of synthetic analogs. Mycestericins D, E, F and G suppressed the proliferation of lymphocytes in the mouse allogeneic mixed lymphocyte reaction.

The upper dermal sheath has a potential to regenerate the hair in the rat follicular epidermis

It has been established that the dermal papilla and the lower dermal sheath of a hair follicle can induce a new hair bulb in follicular epidermis. However, the upper dermal sheath has been believed not to have such an inductive capacity. In contrast to this generally accepted notion, the present study claims the inductive capacity of the upper dermal sheath of a rat vibrissa follicle, as pelage-type hairs were autonomously produced in the amputated upper halves of the follicles when implanted under the kidney capsule for 8 weeks. The study with monoclonal antibodies specific to different follicular tissues clearly revealed the regeneration of small hair bulbs in these implants and suggested that the fine hairs were formed as a result of the interaction between the upper dermal sheath cells and the follicular basal cells. Newly formed bulbs located at two separate sites, one at the amputated end and the other in the upper region of the follicles. No bulb was formed near the bulge area where follicular stem cells had been reported to locate. However, the possibility of involvement of the stem cells in the bulb formation remains, as migration and rearrangement of epidermal cells had occurred in the implants. Together with the comparative experiments on the inductive potential of various dermal compartments, the present study showed that the upper dermal sheath possesses a hair-inducing ability which is weak, as compared to the lower dermal compartments, but sufficient to induce the follicular epidermis to differentiate into the pelage-like hair-producing bulb, and would be activated only under this specific condition.

Unilateral ocular cicatricial pemphigoid with circulating IgA and IgG autoantibodies reactive with the 180 kD bullous pemphigoid antigen

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Immunolocalization of GLUT1 and connexin 26 in the rat placenta

Interhemal membrane in the rat placenta is composed of three trophoblastic layers and endothelial cells. GLUT1, an isoform of the facilitated-diffusion glucose transporter, is abundant in the cells of the placental barrier, i.e., syncytiotrophoblastic layers I and II. GLUT1 is localized at the plasma membranes of the maternal-blood side of syncytiotrophoblastic layer I, and of the fetal-blood side of syncytiotrophoblastic layer II. Double-immunofluorescence microscopy has shown that connexin 26 is present between these GLUT1-positive sites, i.e., between syncytiotrophoblastic layers I and II. Immunogold electron microscopy has revealed that connexin 26 is localized in the gap junctions connecting the two layers. Connexin 26 in these layers therefore makes them functionally a single syncytial layer for the transfer of small molecules such as glucose in the rat placental barrier. These results suggest that glucose transfer in the rat placental barrier is carried out as follows: GLUT1 is used for the entry of glucose into the cytoplasm of syncytiotrophoblastic layer I, connexin 26 for the transfer of glucose from syncytiotrophoblastic layer I to syncytiotrophoblastic layer II, and GLUT1 for the exit of glucose to the fetal circulation.

Evaluation of nitric oxide formation from nitrates in pig coronary arteries

To clarify the hypothesis that organic nitrates are converted to nitric oxide (NO) via nitrite ion (NO2-) by glutathione S-transferase, the metabolic conversion of four nitrates was examined in pig coronary arteries and compared with that in rat liver. Nitrates caused the relaxation of the artery muscles with the order of nitroglycerin > isosorbide dinitrate > nicorandil > or = nipradilol, whereas the order of NO formation in the arteries was nitroglycerin > isosorbide dinitrate > nipradilol > nicorandil. The same order of NO formation from the nitrates was also observed in liver cytosol. Nicorandil may cause more relaxation than nipradilol by both NO releasing and other (unknown) actions. Although the order of the potency in NO2- formation from the nitrates in liver cytosol was the same as that seen in NO formation, NO2- was not detected in pig coronary arteries. Thus NO2- formation from the nitrates correlated with NO formation in liver cytosol but not in pig arteries. When nonenzymatic and enzymatic NO formations from nitroglycerin were examined in the arteries, the enzymatic NO formation, which was not inhibited by glutathione S-transferase inhibitors, was 13% of the total NO. These results indicate that in pig coronary arteries, nitrates release NO mostly through a nonenzymatic manner, although there is a slight amount of enzymatically produced NO, and glutathione S-transferase may not contribute to the enzymatic NO formation.

Involvement of nitric oxide and eicosanoids in platelet-activating factor-induced haemodynamic and haematological effects in dogs

1. Platelet-activating factor (PAF) is a phospholipid mediator with potent cardiovascular and haematological actions. But its mechanisms of action in vivo have not been fully elucidated, probably due to difficulties arising from previous findings that the effects of PAF are largely mediated by the release of a variety of other autacoids. In the present study, the roles of nitric oxide and eicosanoids in the effects of PAF (0.01-0.25 microgram kg-1 i.v.) on systemic and pulmonary vasculatures and circulating blood cell count were pharmacologically evaluated in anaesthetized dogs. 2. Higher doses of PAF (> 0.1 microgram kg-1) produced a biphasic systemic hypotension. The first hypotension seen 30 s after the injection was accompanied by a decrease in systemic vascular resistance, thrombocytopenia and leukopenia, while the second hypotension seen 1-2 min after PAF was accompanied by a marked rise in pulmonary vascular resistance and decreases in aortic blood flow and cardiac contractility. Lower doses of PAF (0.01 - 0.05 microgram kg-1) caused only the first responses in a dose dependent manner. 3. Pretreatment with indomethacin inhibited the second responses to PAF without affecting the first responses. The thromboxane A2/prostaglandin H2 (TP)-receptor antagonist vapiprost blocked the PAF-induced rise in pulmonary vascular resistance. AA-861, a 5-lipoxygenase inhibitor, attenuated the PAF-induced cardiac depression. The nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester inhibited the PAF-induced early decrease in systemic vascular resistance. 4. All observed changes in haemodynamics and blood cell count after PAF were almost abolished by TCV-309, a PAF-receptor antagonist. 5. Reproducible hypotension and thrombocytopenia produced by a lower dose of PAF (0.05 microgram kg-1) were respectively attenuated and potentiated by pretreatment with NG-nitro-L-arginine, another nitric oxide synthase inhibitor. Administration of L-arginine reversed the effects of the nitric oxide synthase inhibitor. 6. These results indicate that PAF-receptor-mediated production of not only eicosanoids but also nitric oxide may contribute to the cardiovascular and haematological responses to PAF in the dog.

Characterization of a human MSX-2 cDNA and its fragment isolated as a transformation suppressor gene against v-Ki-ras oncogene

A cDNA (termed CT124) encoding a carboxyl-terminal fragment of the human homeobox protein MSX-2 was found to induce flat reversion when expressed in v-Ki-ras-transformed NIH3T3 cells. Although the expression of endogenous MSX-2 gene is low in most of the normal adult tissues examined, it is frequently activated in carcinoma-derived cell lines. Likewise, the gene is inactive in NIH3T3 cells but is transcriptionally activated after transformation by v-Ki-ras oncogene, suggesting that the intact MSX-2 may play a positive, rather than suppressive, role in cell transformation. To test this possibility, we isolated a near full-length human MSX-2 cDNA and tested its activities in two cell systems, i.e. fibroblast and myoblast. In NIH3T3 fibroblasts, although the gene by itself failed to confer a transformed phenotype, antisense MSX-2 cDNA as well as truncated CT124 cDNA interfered with the transforming activities of v-Ki-ras oncogene. In C2C12 myoblasts, MSX-2 was found to suppress MyoD gene expression, as do activated ras oncogenes, under certain culture conditions, and CT124 was found to inhibit the activities of both MSX-2 and ras in this system as well. Our findings not only suggest that CT124 may act as a dominant suppressor of MSX-2 but also raise the possibility that MSX-2 gene may be an important downstream target for the Ras signaling pathways.

Isolation and identification of two new diterpene glycosides from Nicotiana tabacum

Two new diterpene glycosides containing 20-hydroxygeranyllinalool were isolated and identified from Nicotiana tabacum. These compounds consisted of five molecules of glucose and/or rhamnose. The locations of the aglycone and glycosides in the molecules were determined by 2D-NMR with the HMBC technique. The structures were (6E,10E,14Z)-20-hydroxygeranyllinalyl-3-O- [alpha-L-rhamnopyranosyl (1 --> 4)]-beta-D-glucopyranoside-20-O- [beta-D-glucopyranosyl (1 --> 2)]-[alpha-L-rhamnopyranosyl (1 --> 6)]-beta-D- glucopyranoside and (6E,10E,14Z)-20-hydroxygeranyllinalyl-3-O- [alpha-L-rhamnopyranosyl (1 --> 4)]-beta-D-glycopyranoside-20-O- [alpha-L-rhamnopyranosyl (1 --> 4)]-[alpha-L-rhamnopyranosyl (1 --> 6)]-beta-D- glucopyranoside.

Dystrophin-positive muscle fibers following C2 myoblast transplantation into mdx nude mice

To determine when and how the dystrophin-positive muscle fibers are formed after myoblast transplantation into dystrophin-negative muscles, the tibialis anterior (TA) muscle from mdx nude mouse was chronologically examined after C2 myoblast transplantation by immunohistochemical and glucose 6-phosphate isomerase (GPI) isoenzyme analyses. The host TA muscle transplanted with C2 myoblasts became necrotic with accumulation of basic fibroblast growth factor in the necrotic areas. This may stimulate concomitant proliferation of the host satellite cells and C2 myoblasts. Small dystrophin-positive muscle fibers appeared in the necrotic areas 3 days after transplantation. This TA muscle contained two different kinds of homodimer GPI isoenzymes but did not contain the heterodimer, suggesting rare fusion of host and donor cells. The dystrophin-positive muscle fibers in the necrotic areas rapidly increased in number and in size by 7 days, but they were smaller than the original host muscle fibers. They had central nuclei, indicating that they were regenerating fibers. The presence of heterodimer GPI isoenzyme in these muscles indicated that the regenerating fibers were mosaic host/donor muscle fibers. The dystrophin-positive muscle fibers are probably formed first by fusion of donor cells with each other and then later by the fusion of host satellite and donor cells.

Crystal structure of Ustilago sphaerogena ribonuclease U2 at 1.8 A resolution

The crystal structure of purine-specific ribonuclease (RNase) U2 from Ustilago sphaerogena has been solved by the molecular replacement methods using RNase T1 as a search model. The structure, with 114 amino acid residues, 141 water molecules, and a sulfate ion, is refined to an R factor of 0.143 at 1.8 A resolution. As evidenced by the electron densities, residues 49 and 50 are revised to Glu 49 and Asp 50, respectively, and also Asp 45 is identified as a beta-isomerized form to L-isoaspartate with a beta-peptide linkage. RNase U2 consists of a beta-hairpin at residues from 7 to 14, a 4.4-turn alpha-helix from 16 to 32, a central beta-sheet with five strands, and a protruding beta-turn from 74 to 77. As for the catalytic site residues, His 41, Glu 62, and Arg 85 are located as constituents of the central beta-sheet, and Tyr 39 and His 101 are situated at either end of the beta-sheet. The side chains of Tyr 39, Glu 62, Arg 85, and His 101 are hydrogen-bonded to the sulfate ion which marks the RNA phosphate position. Though the side chain of His 41 is pointing away from the sulfate, small conformational adjustments of His 41 enable the side chain to interact with either the phosphate or the ribose group of RNA. The loop region from Tyr 44 to Asp 50 is ascribed to the base recognition site where Glu 49 is involved in adenine recognition. beta-Isomerized Asp 45 suggests that this region is conformationally flexible and alterable.

Low expression of adhesion molecules in a case of cutaneous T-cell lymphoma

A case of cutaneous T-cell lymphoma (CTCL) with low expression of the adhesion molecules lymphocyte function-associated antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1), and very late antigen-4 (VLA-4) is described. The patient was a 90-year-old man with red round homogeneous tumors on his scalp, trunk, and extremities. He had no history of definite erythema or plaque stage. A biopsy sample taken from a tumor revealed massive infiltration of atypical lymphocytes in the reticular dermis and subcutis with a definite clear zone. The atypical lymphocytes were medium-sized with slightly convoluted nuclei. Immunohistochemically, the infiltrates showed the phenotype of so-called memory T cells. On the basis of these features, the case was diagnosed as CTCL. Expression of LFA-1, ICAM-1 and VLA-4 on the infiltrates was 9%, 13% and 11%, respectively, which is much lower than that in classic mycosis fungoides. This finding suggests that loss of these adhesion molecules may contribute to loss of epidermotropism in the advanced stage of CTCL.

Induction of single ovulation by sequential follicle-stimulating hormone and pulsatile gonadotropin-releasing hormone treatment

OBJECTIVE

To induce single follicular ovulation by sequential treatment with FSH and pulsatile GnRH.

DESIGN

Prospective study.

PATIENTS

Eighteen hypogonadotropic anovulatory patients.

INTERVENTIONS

In sequential treatment, daily FSH injection was switched to pulsatile GnRH administration (20 micrograms/120 minutes SC) when the follicle diameter reached 11 mm. In conventional FSH treatment, daily FSH injection was continued. In both cycles, hCG was given when the diameter of the dominant follicle reached 18 mm.

MAIN OUTCOME MEASURES

Developed follicle numbers and serum FSH concentrations during treatment.

RESULTS

Single follicular development was achieved in 80.0% of cycles by sequential treatment but in no cycle by conventional FSH treatment. The number of developed follicles was 1.26 +/- 0.55 (mean +/- SD) on sequential treatment and 3.94 +/- 1.48 on conventional FSH treatment. Preovulatory FSH level was significantly lower on sequential treatment than on conventional FSH treatment (5.26 +/- 1.80 versus 11.55 +/- 3.43 mIU/mL [conversion factor to SI unit, 1.00]).

CONCLUSION

The sequential treatment achieved single follicular development without complications. The sequential FSH-pulsatile GnRH treatment may offer a better chance for development of a single dominant follicle and ovulation.

A new retroviral vector for detecting mutations and chromosomal instability in mammalian cells

A retroviral vector carrying both forward (neo) and backward (herpes simplex virus thymidine kinase or HSV-TK gene) selection markers was constructed as a substrate for mutational assay in mammalian cells. The cells infected with this virus are first selected with G418, mutagenized and then selected with the anti-herpes drug acyclovir (ACV). Since HSV-TK, but not the host TK, is capable of converting ACV to a toxic metabolite, cells retaining the intact HSV-TK gene fail to survive, while the cells carrying a mutated HSV-TK gene or which have lost the gene can form colonies in the presence of ACV, making it possible to detect the genetic defects in a positive manner. It is also possible to discriminate between small mutations and large deletions by checking the presence of the linked marker, neo. As a model experiment, we prepared an uncloned pool of rat fibroblast cells (CREF) infected with this virus and irradiated them with increasing doses of ultraviolet light. Dose-dependent increases in the number of ACV-resistant colonies were observed. Structural analysis of the HSV-TK gene in these clones revealed point mutations or small deletions in the majority of the cases. Since it requires no pre-existing genetic markers in the host cells, this system may be used for a wide variety of mammalian cells and provides a useful tool to assess both their susceptibility to various mutagens and their genomic instability.

Blood flow velocity waveforms of the fetal middle cerebral artery in pregnancies complicated by diabetes mellitus

Fetal blood flow velocity waveforms of the middle cerebral artery were measured by pulsed Doppler ultrasound in 43 pregnant women with diabetes mellitus (33 class B, 3 class C, 6 class D and 1 class R). The recordings were performed between 24 and 38 weeks of gestation. A total of 122 recordings were analyzed prior to establishing the resistance index (RI = peak systolic velocity minus diastolic velocity/peak systolic velocity). The mean maternal serum glucose was 124.3 mg/dl (range: 72.7 to 281.5 mg/dl), the mean hemoglobin A1c was 6.03% (range: 3.3 to 11.0%) and the mean fructosamine level was 255.97 mumol/L (range: 205 to 397 mumol/L). The resistance index did not differ between the fetuses of the diabetic mothers in our study population. Additionally, no significant correlation was noted between RI values and serum glucose levels (r = 0.03), hemoglobin A1c levels (r = 0.13) or fructosamine levels (r = 0.04) during the period of 26 to 34 gestational weeks. These data indicate that the RI within the fetal cerebral artery is unaffected by the maternal glycemic control when mean serum glucose levels are below 280 mg/dl.

Mechanism of anovulation in hyperprolactinemic amenorrhea determined by pulsatile gonadotropin-releasing hormone injection combined with human chorionic gonadotropin

OBJECTIVE

To clarify the mechanism of anovulation in hyperprolactinemic anovulatory women by subcutaneous (SC) pulsatile GnRH injection.

DESIGN

Prospective clinical study.

SETTING

Studies were made on at the Department of Obstetrics and Gynecology, the University of Tokushima, School of Medicine.

PATIENTS

Six hyperprolactinemic (group 1) and 7 normoprolactinemic (group 2) anovulatory patients were studied.

INTERVENTIONS

After examinations of pulsatile secretion of LH, the GnRH test, thyrotropin-releasing hormone test and estrogen test, pulsatile GnRH treatment (20 micrograms/2 hours SC) was performed. Two protocols were tested on each patient. In the non-hCG protocol, GnRH treatment was continued until ovulation. In the hCG protocol, 5,000 IU of hCG was injected to induce ovulation when follicles were fully mature.

MAIN OUTCOME MEASURE

The rates of follicular maturation and ovulation, serum E2 and P in the two groups.

RESULTS

Pulsatile LH secretion was impaired in both groups. LH release 48 hours after estrogen injection was impaired in group 1 but not in group 2. Follicles matured on pulsatile GnRH treatment in all cycles in both groups. However, with the non-hCG protocol, ovulation occurred in only 17% of group 1, but in 89% of group 2. With the hCG protocol ovulation occurred in all cycles in both groups.

CONCLUSIONS

The main cause of anovulation is impaired gonadotropin pulsatility and derangement of the estrogen-positive feedback effect on LH secretion in hyperprolactinemic patients, their ovarian response to gonadotropin being well maintained. Subcutaneous pulsatile GnRH therapy combined with hCG can be used as an alternative to bromocriptine treatment for induction of ovulation in these patients.