Transcriptional control of the rat heme oxygenase gene by a nuclear protein that interacts with adenovirus 2 major late promoter

Induction of rat heme oxygenase is mediated by at least two factors: its substrate heme and heat shock (Shibahara, S., Müller, R.M., and Taguchi, H. (1987) J. Biol. Chem. 262, 12889-12892). We have identified the cis-acting element of the rat heme oxygenase gene (HO gene), that was specifically bound by a nuclear protein prepared from rat glioma cells. We have termed this protein as heme oxygenase transcription factor (HOTF), whose estimated molecular weight is about 40,000. The element identified is CCACCACGTGACTCGAG (-51/-35) located just upstream of TATA-like sequence. The functional studies indicate that this sequence is required for the accurate and efficient initiation of transcription from the HO gene promoter. Since the HOTF-binding element is similar to the upstream promoter sequence (UPS) of the adenovirus 2 major late promoter (Ad2MLP), we examined whether rat HOTF is homologous to the upstream stimulatory factor (USF) or major late transcription factor previously identified in HeLa cells, which interacts with the UPS and activates the transcription from the Ad2MLP. HOTF specifically binds to the UPS of Ad2MLP, whereas HOTF failed to form a stable complex with the mutated HOTF-binding element lacking a GTGA sequence (-44/-42 of the HO gene), the sequence of which is identical to a core sequence of the USF-binding sites. Moreover, we show that like USF, HOTF is heat stable. These results suggest that HOTF may be homologous to USF or the major late transcription factor. Since USF is present in uninfected cells, it is conceivable that the expression of the HO gene is regulated at least in part by USF.

[Clinical effects of intravesical instillation of polymyxin B in patients with acute cystitis]

The effectiveness of intravesical instillation of Polymyxin B was studied in 17 patients suffering from acute cystitis. The 17 patients, all female, had an average age of 42 years. The average duration between the onset of symptoms and the initial visit to the hospital was 4.6 days. The causative organisms were 15 strains of E. coli and 1 each of P. rettegeri and K. pneumonia, respectively. Improvement of symptoms was observed in 76% of the cases but pyuria was cleared in only 47% of the cases. Clinical results were excellent in 8 cases (47%), good in 6 cases (35%) and poor in 3 cases (18%). The overall effectiveness rate was 82%. No appreciable amount o Polymyxin B, was detected in the serum of 4 patients examined.

Expression of lacto series type 2 antigens in human renal cell carcinoma and its clinical significance

We performed immunohistochemical examination of serial sections of human fetal and adult renal tissue as well as human renal carcinoma tissue, using monoclonal antibodies T5A7, 1B2, FH2, FH4, and FH6. These monoclonal antibodies were directed to lacto series type 2 antigens with sugar-chain structures: lactosylceramide, lactoneotetraosylceramide (paragloboside), Lex (a chemically well-defined fucosyl carbohydrate antigen), difucosyl Lex, and sialosyl-difucosyl Lex, respectively. The staining pattern in fetal renal tissue changed significantly according to the stage of organogenesis. In addition, expression of the antigens, especially paragloboside and sialosyl-difucosyl Lex, was closely related to the prognosis of the patient. These results suggest that the expression of a series of oncofetal antigens in development or differentiation of organs is reflected in the reversion to an immature pattern of antigenic expression in tumor tissue. The pattern of antigen expression in renal tumors offers a good criterion for ascertaining the degree of tumor differentiation and malignancy and is valuable for determining prognosis.

D-600 sensitive and insensitive spontaneous contractions in the guinea-pig hepatic duct

The mechanical properties of the longitudinally cut preparations of the guinea-pig hepatic duct were studied. About 42% of the preparations (18 of 43 preparations) showed spontaneous phasic contractions which were unaffected by either tetrodotoxin, guanethidine or atropine. About 60% of them exhibited phasic contractions which appeared at irregular frequencies in the same tissue and varied in size. This sort of contractions usually accompanied small contractions. In about 20%, contractions occurred constantly in frequency (about 6-14 every 10 min) and in size. The remaining 20% showed twitch-like contractions which occurred sporadically. These contractions were classified into two types depending upon the susceptibility to the Ca2+ entry blocker, D-600. D-600 (1-100 microM) strongly suppressed both regularly occurring contractions and twitch-like ones. On the other hand, the drug was ineffective on irregularly occurring contractions. The Ca2+ sources underlying these contractions were discussed.

Immunohistochemical comparison of Lea, monosialosyl Lea (CA 19-9), and disialosyl Lea antigens in human colorectal and pancreatic tissues

The CA 19-9 antigen is a monosialosyl Lea blood group antigen which has been shown to be a useful tumor-associated antigen for the diagnosis of gastrointestinal cancers. Recently, a sialylated derivative of this antigen, disialosyl Lea, was isolated from a colon cancer liver metastasis and a monoclonal antibody (FH7) recognizing this novel determinant was developed. The present study simultaneously compared the expression of Lea, monosialosyl Lea, and disialosyl Lea antigens in a variety of nonmalignant, premalignant, and malignant tissues of the colorectum and pancreas with an aim toward elucidating whether disialosyl Lea is expressed as a tumor-associated antigen. In normal colonic mucosa, disialosyl Lea expression closely resembled Lea expression in overall frequency, segmental distribution, and cellular localization whereas monosialosyl Lea (CA 19-9) was essentially absent. Along the crypt axis, Lea was more often expressed in goblet cells of the upper crypt whereas disialosyl Lea was found in goblet cells along the entire crypt. Fetal colonic mucosa expressed all three antigens, as did most colorectal cancers regardless of location within the colon or degree of differentiation. The majority of hyperplastic polyps and practically all adenomatous polyps also expressed these three antigens, and in adenomas, antigen expression was independent of polyp size, villous morphology, or degree of dysplasia. In the normal pancreas, the three antigens were expressed on ductal, ductular and centroacinar cells of all specimens. The majority of pancreatic cancers expressed all three antigens. Thus, in the normal colon, the absence of monosialosyl Lea (CA 19-9) in the presence of disialosyl Lea suggests that an alpha 2,6 sialyltransferase is active, which results in the masking of CA 19-9 antigen expression. These results further support the concept that specific sialyltransferases play a role in regulating the expression of tumor-associated antigens.

Two alpha-adrenergic contractions with different Ca2+ activation mechanisms in response to field nerve stimulation in the circular smooth muscle of guinea-pig vas deferens

1. Two noradrenergic components of contraction were induced by field nerve stimulation of the circular smooth muscle of guinea-pig vas deferens. One component occurred during the stimulation (former-response) and the other component occurred after stimulation had ceased (after-response), with a distinct tension fall between these two responses. 2. The effects of stimulation frequency and duration upon these components were examined. 3. Prazosin (0.05-0.5 microM) suppressed both responses, whereas nifedipine (0.02 microM) suppressed only the after-response. 4. It is suggested that in this tissue there are two neurogenic alpha-adrenergic contractions which possess different Ca2+ activation mechanisms. The former-response is due to an increase in cytoplasmic Ca2+ concentration through a pathway independent of action potentials, while the after-response is attributed to action potentials arising as a secondary response to the released noradrenaline.

Involvement of cholinergic nerves in excitatory junction potentials through prejunctional nicotinic receptors in the guinea-pig vas deferens

1. The effects of various drugs on excitatory junction potentials (EJPs) elicited by field stimulation of the longitudinal smooth muscle of the guinea-pig vas deferens were examined using the sucrose-gap method. 2. Field stimulation with a single pulse (1.0 ms, 20 Vcm-1) produced a depolarization of 3-7 mV. When a single pulse was repetitively applied, the depolarization showed summation, resulting in action potential firing. 3. Tetrodotoxin (1 microM) and guanethidine (1 microM) completely suppressed EJPs whilst propranolol (1 microM) or atropine (0.1 microM) did not affect them. Phentolamine (1 microM) slightly potentiated EJPs. 4. d-Tubocurarine (dTC) at lower concentrations (0.5-2 microM) suppressed EJPs, but at a higher concentration (20 microM) the drug little affected them. 5. Hexamethonium (C6) suppressed EJPs at low concentrations (0.5-5 microM), but potentiated them at a higher concentration (50 microM). 6. Either dTC or C6, each at a concentration of 0.5 microM, did not affect the depolarization induced by exogenously applied ATP or noradrenaline. 7. These results suggest that in this tissue cholinergic nerve activity can contribute to the magnitude of EJPs, and that this effect is mediated through nicotinic receptors.

[Initial basic and clinical evaluation of a solid-phase immunoradiometric assay for sialyl SSEA-1 antigen: 1. Evaluation of assay conditions and normal values]

We describe a solid-phase immunoradiometric sandwich assay method for a new tumor marker, sialyl SSEA-1 (sialyl LeX-i), using RIA kits (prepared by Otsuka Assay Laboratories). The assay required only duplicate 20-microliter samples, and the concentration of sialyl SSEA-1 antigen in serum was determined with reference to a standard curve ranging from 0 to 224 arbitrary unit/ml. The intra- and inter-assay reproducibilities and analytical recovery of antigen were excellent. The cut-off value (38 unit/ml) was obtained as mean + 2SD, which was calculated from the antigen concentration in sera from 1,105 healthy individuals. Also described are the alterations of normal values by age, sex, and Lewis blood group status.

[Initial basic and clinical evaluation of a solid-phase immunoradiometric assay for sialyl SSEA-1 antigen: 2. Evaluation of clinical significance]

The clinical significance of serum sialyl SSEA-1 antigen was evaluated using the sera of 1261 patients with malignant tumors and 717 patients with non-malignant diseases measured with Otsuka Assay Laboratories' RIA Kits. The results indicate that the antigen was frequently elevated in the sera from the patients with various adenocarcinomas, including lung (45%), pancreas (64%) and ovary (57%). The false positive incidence of antigens in the sera from the patients with non-malignant disorders was as low as 4.9%. No correlation was observed with other tumor markers examined in this study, and the diagnostic efficiency increased significantly by the combined determination of sialyl SSEA-1 antigen level with other markers. The serial determination of the serum sialyl SSEA-1 antigen level has a clinical utility also in monitoring the patients with adenocarcinoma receiving surgical operation and/or chemotherapy as indicated by the results of the longitudinal observation of the patients.

Lack of involvement of Ca2+ conductance change in ATP-induced depolarization of the guinea-pig vas deferens

The double sucrose-gap method was used to examine the electrical responses of the guinea-pig vas deferens to ATP and their possible dependence on external Ca2+. Normally ATP induced a depolarization and an increase in membrane conductance and both effects were concentration-dependent. The reversal potential of the 10(-4) M ATP-induced depolarization was 27.1 mV positive to the resting membrane potential of the tissue. This value was quite similar to that previously obtained for the 3 X 10(-5) M ATP-induced depolarization. The smooth muscle membrane was depolarized by 5.9 mV in a Ca-free medium, in which ATP also caused a depolarization, associated with an increase in membrane conductance. The reversal potential of the depolarization induced by ATP (10(-4) M) in the Ca-free medium was 26.5 mV positive to the resting membrane potential. The results suggest that, in this tissue, ATP induces membrane depolarization with little effect on Ca2+ conductance.

Expression of LewisX and sialylated LewisX antigens in human colorectal polyps

The LewisX (LeX) antigen [characterized by trisaccharide Gal beta 1----4 (Fuc alpha 1----3)N-acetylglucosamine] is an oncodevelopmental antigen in the human colon. Monoclonal antibodies (MoAbs), anti-SSEA-1 and AH8-183, which recognize LeX antigen either on short oligosaccharide side chains or as a terminal immunodeterminant on longer carbohydrate side chains of glycoconjugates, bind to most colon cancer tissues but also to some normal colon mucosae. However, the monoclonal antibodies FH1, FH4, FH6, and IB9, which recognize extended difucosylated and trifucosylated LeX structures or their sialylated derivatives, are more cancer-associated because they rarely bind to normal colon mucosa. In the present study, these MoAbs were used to compare the expression of various LeX-related antigens in premalignant (adenomatous) and nonpremalignant (hyperplastic) colorectal polyps. Antigen expression in polyps was also compared to antigen expressions of normal colon mucosa and colon cancer tissues. The four MoAbs recognizing extended LeX antigens bound to adenomatous polyps (APs) significantly more than to hyperplastic polyps (HPs). In contrast, anti-SSEA-1 and AH8-183 recognizing monofucosyl LeX were less able to distinguish between APs and HPs. In APs, staining with the four MoAbs recognizing extended LeX antigens correlated with the premalignant parameters of larger polyp size, more severe dysplasia, and increased villose component. However, staining with AH8-183 correlated only with polyp size, and anti-SSEA-1 correlated only with polyp size and degree of dysplasia. In general, the staining frequency of HPs was similar to that of normal colon mucosa, although FH6, which did not stain any specimens of normal mucosa, stained a few HPs. The staining frequency of APs was less than that of colon cancer tissues, but these differences were generally not statistically significant. In conclusion, extended LeX antigens and their sialylated derivatives are cancer-associated antigens that are expressed preferentially in premalignant colon polyps, that tend to correlate with malignant potential in these polyps, and that may eventually help to define mechanisms involved in the polyp-to-cancer sequence.

Possible relationship between the release of calcium ions and inactivation of the potassium conductance induced by noradrenaline in smooth muscle of the guinea-pig vas deferens

In order to examine whether any change in cytoplasmic Ca2+ concentration occurs during the noradrenaline (NA)-induced change in the membrane potential, the isometric tension of smooth muscle of the guinea-pig vas deferens was recorded together with membrane potentials using the sucrose-gap method. NA induced a depolarization and an increase in cytoplasmic Ca2+ comprising two (initial and second) phases. In time courses, the depolarization and the second phase of the increase in cytoplasmic Ca2+ were similar. Only at the phase around the onset of the depolarization, the membrane conductance was increased but then, it was decreased. Lowering the external Ca2+ concentration and application of D600 suppressed all of the NA-induced responses. In addition, D600 diminished the size of the NA-induced decrement in the membrane conductance. The present results suggest that the initial phase of the increase in the cytoplasmic Ca2+ is due to the influx of Ca2+ and the second phase, probably to the release of Ca2+ from some intracellular stores. It was discussed that the release of Ca2+ might occur at the internal surface of the membrane, and the membrane might be left less permeable to K+ as a result.

Pharmacological studies on the role of cholinergic nerves in the neuromuscular transmission in the circular smooth muscle of guinea-pig vas deferens

Effects of various drugs were examined on the mechanical responses of the circular smooth muscle of guinea-pig vas deferens evoked by field stimulation and ACh. During field stimulation (0.1 msec, 3-80 Hz) a contraction consisting of two (initial and second) phases occurred. In addition, another contraction (after-response) occurred after the cessation of the stimulation particularly at higher frequencies (40-80 Hz). Guanethidine (2-20 microM) suppressed both the initial and second phases of the field stimulation-evoked responses. Prazosin (0.1-1 microM) suppressed the second phase but minimally affected the initial phase. Both phases were suppressed by atropine (0.1-1 microM) and potentiated by physostigmine (5 microM). dTC (0.5-20 microM) did not suppress either phase but potentiated the second phase. ACh (0.28-280 microM) produced a contraction, which was reduced by atropine but was little affected by either dTC or TTX. These results suggest that at the postsynaptic site of the neuromuscular junction in this tissue the sympathetic process activates the smooth muscle through two different types of receptor; one is non-noradrenergic and the other is an alpha-adrenoreceptor. In addition, a cholinergic process also activates the smooth muscle through muscarinic receptors.

Possible interaction of cholinergic nerves with two different (pre and post) sites of the neuromuscular junction in guinea-pig vas deferens

Effects of various drugs on the mechanical responses of the longitudinal smooth muscle of guinea-pig vas deferens evoked by ACh and field nerve stimulation were examined. ACh (28-280 microM) produced a contraction consisting of two phases. The first phase of the contraction was suppressed by guanethidine and by nicotinic antagonists. The second phase was suppressed only by atropine. Both phases were unaffected by TTX or prazosin. Field stimulation (0.1 msec, 40 Hz) evoked contractions which also consisted of two (early and late) phases. Guanethidine (0.1-1 microM) suppressed both phases whilst prazosin (1 microM) suppressed only the late phase. Atropine (0.1 microM) suppressed both phases whilst physostigmine (5 microM) potentiated both phases of field stimulation-evoked contractions. Pentolinium suppressed both phases of field stimulation-evoked contractions at low concentrations (2-10 microM), but potentiated them at a higher concentration (100 microM). dTC at a low concentration (0.5 microM) suppressed the early phase, but slightly enhanced the late phase of field stimulation responses. At a higher concentration (20 microM), dTC potentiated both phases of the response. Pentolinium and dTC did not affect the contractions induced by 90 mM-K ions, ATP or NA. These results suggest that cholinergic nerves possess an excitatory action not only directly at the smooth muscle but also at the noradrenergic nerve terminals. The role of each receptor is discussed further.

Izupeptins A and B, new glycopeptide antibiotics produced by an actinomycete

In the course of screening for new high molecular weight peptidoglycan synthesis inhibitors, izupeptins A and B, antibiotics active against Gram-positive bacteria including methicillin-resistant Staphylococci and Clostridium were discovered. The antibiotics were found to be new members of the glycopeptide antibiotic family, namely of the vancomycin type, based on chemical and spectroscopic data. The molecular weight of izupeptin A was determined to be 1,475 by SI (secondary ion)-MS (integer molecular weight, 1,473), and it contains two chlorine atoms.

Evidence for suppression of potassium conductance by noradrenaline in smooth muscle of guinea-pig vas deferens

The ionic dependency was examined in the reversal potential of the NA-induced membrane depolarization of smooth muscle of the guinea-pig vas deferens, using the double sucrose-gap method. In the control (5.9 mM K) solution and solutions containing 20 and 60 mM K ions, replaced with equimolar amount of Na ions, the reversal potential was negative to the membrane potential at the steady state in each solution, by 19.5, 15.1 and 13.2 mV, respectively. Taking account that the higher external K concentration causes the larger membrane depolarization, these results indicate that the reversal potential shifted toward the positive direction as the external K concentration was increased. On the other hand, the calculated equilibrium potential of K ions in those solutions is -88, -52 and -24 mV, respectively. In those solutions, furthermore, the equilibrium potential of Na ions is 42, 38 and 29 mV, respectively. However, the equilibrium potentials of Ca and Cl ions should be unchanged. Therefore, it is suggested that the reversal potential of the NA-induced depolarization varied in the given different solutions compatibly only with the change in the K equilibrium potential. This provides evidence that in this tissue, NA induces a reduction in the K conductance of the cell membrane.

Dual excitatory actions of acetylcholine at the neuromuscular junction in the guinea-pig vas deferens

The action of acetylcholine (ACh) on the smooth muscle of guinea-pig vas deferens was studied using the sucrose-gap method. ACh, when applied at a concentration of 10(-6) M, evoked a depolarization of the smooth muscle membrane which was slow in time course (slow depolarization). When ACh was applied at higher concentrations, another depolarization which was fast in time course (fast depolarization) occurred, overlapping the early part of the slow depolarization. The magnitudes of both depolarizations were concentration-dependent on ACh. TTX and adrenergic receptor antagonists had little effect on either depolarizations, while guanethidine and nicotinic receptor antagonists mainly suppressed the fast depolarization. In contrast, atropine suppressed the slow depolarization. The membrane conductance observed by current application, was reduced during the slow depolarization, and the reversal potential of the depolarization was 18.3 mV negative to the resting membrane potential. Whereas, the reversal potential of the fast depolarization was 27.6 mV positive to the resting membrane potential. This reversal potential was quite similar to that of the adenosine triphosphate (ATP)-induced depolarization, previously observed in the same tissue. From these observations, it is suggested that in the guinea-pig vas deferens, ACh acts on nicotinic receptors at the sympathetic postganglionic nerve terminal, causing the release mostly of a non-adrenergic transmitter, probably ATP. In addition, ACh also acts on muscarinic receptors on the smooth muscle membrane, inducing membrane depolarization resulting from a reduction of the membrane conductance to potassium ions.

Effect of dilazep on decrease in myocardial pH during ischemia in dogs

The present study was undertaken in order to examine whether dilazep (1,4-bis-[3-(3,4,5-trimethoxybenzoyloxy)propyl]perhydro-1, 4-diazepine dihydrochloride monohydrate) attenuates myocardial acidosis induced by coronary artery occlusion in dogs. In dogs with nonischemic normal heart, dilazep (300 or 500 micrograms/kg i.v.) increased blood flow in the left anterior descending coronary artery (LAD) with a decrease in heart rate and diastolic blood pressure. In other dogs, LAD flow was reduced by an occluder by 57 to 68% (partial occlusion) for 90 min. Partial occlusion for 30 min decreased myocardial pH by 0.67 to 0.87 pH units, increased ST segment of the surface electrocardiogram, and decreased regional myocardial contractile force. Dilazep was injected i.v. 30 min after partial occlusion. The decrease in myocardial pH induced by partial occlusion was attenuated by the injection of 300 micrograms/kg of dilazep insignificantly and by that of 500 micrograms/kg of dilazep significantly. Restoration of myocardial [H+] induced by dilazep was calculated from the myocardial pH data. Dilazep (500 micrograms/kg) restored myocardial [H+] induced by partial occlusion by 56.7%, and saline solution restored it by 27.4% 60 min after the drug injection, the actual restoration induced by dilazep being 29.3%. Dilazep, however, did not restore the ST segment elevation and contractile force decrease. It is concluded that dilazep attenuates myocardial acidosis during ischemia.