Gingival hyperplasia induced by nifedipine

We describe 4 cases of gingival hyperplasia induced by nifedipine, together with clinical and histological findings. Hyperplasia of the interdental papillae was observed in all cases. Histologic examination showed multilayered epithelial parakeratosis with variations in the width, proliferation, reticulation and elongation of the rete pegs. Substitution of another drug and improvement of oral hygiene led to reduction of the gingival overgrowth without gingivectomy. These treatments are essential for gingival hyperplasia induced by nifedipine.

[Clinical investigation on acute respiratory failure in patients with severe hematologic malignancy]

Ten patients with severe hematologic malignancies (four with acute leukemia, three with multiple myeloma, one with prolymphocytic leukemia, one with malignant lymphoma and one with blastic crisis of chronic myelogenous leukemia) developed respiratory failure during the period between April 1986 and May 1990. Clinically, the patients manifested high-fever, dyspnea refractory to oxygen therapy, diffuse pulmonary rales and severe hypoxemia without evidence of cardiogenic pulmonary edema. Chest roentgenograms displayed diffuse alveolar infiltrates. Respiratory failure occurred as early as 48 hours and as late as 66 days after the administration of intensive anti-neoplastic chemotherapy. At that time leukocyte count was between 100/microliters and 54,900/microliters. Marked leukocytosis was observed in two patients with AML and PLL. Respiratory failure was preceded by sepsis in one patient with AML and by pneumonia in nine patients. DIC was diagnosed in four patients. All patients treated with high dose methyl prednisolone (mPSL) within 12 hours after the onset of respiratory failure. Only one patient required assisted ventilation. High dose mPSL had significant effect on seven of ten patients. But three patients died from progressive respiratory failure, sepsis, pneumonia and multi-organ failure.

Effects of a new benzimidazole derivative, NC-1300-O-3, on gastric secretion and gastroduodenal lesions in rats

We examined the effects of a new compound, NC-1300-O-3 (2-[2-N-methyl-N-(2-methylpropyl) amino] benzylsulfinyl benzimidazole), on the gastric mucosal proton pump (H+, K(+)-ATPase) activity, gastric secretion and gastroduodenal lesions in rats. The compound potently inhibited the enzyme activity in a concentration-dependent manner, the IC50 being 5.3 x 10(-6) M at pH 6.0 and 1.4 x 10(-5) M at pH 7.4. NC-1300-O-3 markedly and persistently (for more than 24 hr) inhibited basal gastric secretion in male or female animals when administered by the p.o. route. The compound also significantly inhibited gastric secretion by the intraduodenal (i.d.), intragastric (after pylorus ligation) and i.p. routes, but only weakly by the s.c. route. Repeated p.o. administration of the compound for 1 week also significantly inhibited gastric secretion. Histamine-stimulated gastric secretion was also significantly inhibited by the i.d. administration of the compound. NC-1300-O-3, administered p.o., potently prevented water-immersion stress-, histamine-, indomethacin-, prednisolone- and compound 48/80-induced gastric lesions. In addition, it also significantly prevented the formation of gastric lesions induced by various necrotizing agents. Mepirizole- and cysteamine-induced duodenal ulcers were also prevented by the compound. The antisecretory and antilesion activities of NC-1300-O-3, administrated p.o., were not altered on its combination with 2% NaHCO3.

Stimulation by Bt2cAMP of epidermal mucous metaplasia in retinol-pretreated chick embryonic cultured skin, and its inhibition by herbimycin A, an inhibitor for protein-tyrosine kinase

Epidermal mucous metaplasia of cultured 13-day-old chick embryonic tarsometatarsal skin can be induced by culture in medium containing retinol (20 microM) for only 8-24 h and then in a chemically defined medium without vitamins or serum for 6 days. In the induction of mucous metaplasia, retinol primarily affects the dermal cells and a signal(s) induced in the dermis by excess retinol alters epidermal differentiation toward secretory epithelium. In this work we found that Bt2cAMP (2 mM) stimulated mucous metaplasia severalfold when added to retinol-pretreated skin but inhibited epidermal mucous metaplasia when added together with retinol. Forskolin (100 microM), an activator of adenylate cyclase, also stimulated mucous metaplasia when added to retinol-pretreated skin. On the other hand, transduction in the epidermal cells of a signal(s) induced in dermal cells by excess retinol was inhibited by herbimycin A (500 ng/ml), an inhibitor of protein-tyrosine kinases, and TPA (0.1 microM), an activator of protein kinase C. Hence these findings indicated that cAMP stimulated signal-induced mucous metaplasia, and that transduction of the signal(s) in the epidermal cells required protein-tyrosine kinase and was inhibited by protein kinase C.

Vasoinhibitory effect of NP-252, a new dihydropyridine derivative, in canine cerebral artery

The vasoinhibitory effect of NP-252, a 1,4-dihydropyridine derivative Ca++ antagonist, was examined in canine cerebral artery, and this effect was compared with that of nifedipine. NP-252 (10(-7)M) and nifedipine (10(-6) M) nearly abolished the contraction induced by addition of Ca++ to Ca(++)-free medium containing KC1. NP-252 (10(-6)M) and nifedipine (10(-6)M) attenuated the contraction produced by thromboxane A2 agonist (STA2) in normal medium, and the resultant contractions were 22% (n = 6) and 35% (n = 6) of the control contraction, respectively. The vasoinhibitory effects of NP-252 were significantly stronger than those of nifedipine in canine cerebral artery. NP-252 (10(-7) and 10(-6) M) dose-dependently attenuated nifedipine-resistant Ca(++)-contraction in the presence of STA2 in both canine cerebral and coronary arteries. The inhibitory effect of combined treatment with NP-252 (10(-6) M) and nitroglycerin (10(-6) M) on nifedipine-resistant Ca(++)-contraction in the cerebral artery was additive. These results indicate that NP-252 possesses a stronger vasoinhibitory effect than that of nifedipine in canine cerebral artery.

Ampicillin concentrations in human oral tissues following a single oral administration of lenampicillin

1. Ampicillin concentrations in serum (n = 20), gingiva (n = 12), jawbone (n = 13), dental follicle (n = 12), radicular granuloma (n = 2) and radicular cyst (n = 2) were measured in specimens obtained during 0.5-2.5 hr after a single oral administration of lenampicillin (equivalent to 500 mg of ampicillin). 2. Measurable ampicillin concentrations were found in all serum and tissues. 3. Ampicillin concentrations in serum and tissues except for some gingiva and jawbone exceeded MIC for 90% of clinically isolated strains of alpha-hemolytic Streptococci. 4. Ampicillin concentrations in gingiva and jawbone were below the MIC for 90% in 2 out of 12 and 4 out of 13 specimens, respectively.

Effects of nitroglycerin on stable thromboxane A2 analogue-induced, nifedipine-resistant contraction in canine basilar artery

The stable thromboxane A2 analogue, STA2, caused concentration-dependent contractions in the canine basilar artery. In Ca2(+)-free medium containing EGTA (0.1 mM) and nifedipine (10(-6) M), the addition of Ca2+ (2.5 mM) in the presence of STA2 (10(-8) M) caused a tonic contraction (nifedipine-resistant Ca2(+)-induced contraction). In the basilar artery, nitroglycerin did not significantly affect such nifedipine-resistant Ca2(+)-induced contractions, but nearly abolished the contraction in the coronary artery. The present experiments suggest that the regulatory mechanism of mobilized Ca2+ for the nifedipine-resistant Ca2(+)-induced contraction produced by STA2 in the basilar artery is different from that in the coronary artery.

Effects of extraneuronal accumulation of isoprenaline on cAMP production in perfused rat heart

The effects of extraneuronal accumulation of isoprenaline on the level of cAMP in perfused rat hearts were investigated. When catechol-O-methyl transferase (COMT) was intact, perfusion with isoprenaline (10(-6) M) for 5 min and 30 min (low accumulation of isoprenaline in the heart) enhanced the cAMP level. Propranolol (10(-6) M) significantly decreased the high level of cAMP produced by the perfusion with isoprenaline for 5 min and 30 min (low accumulation of isoprenaline). When COMT was inhibited by tropolone, perfusion with isoprenaline (10(-6) M) for 5 min (slight accumulation of isoprenaline in the heart) slightly increased the level of cAMP, while perfusion for 30 min (high accumulation of isoprenaline in the heart) did not increase the level of cAMP. Propranolol (10(-6) M) significantly decreased the cAMP level produced by 5 min perfusion with isoprenaline, but did not change the level by 30 min perfusion. The perfusion length (5 min and 30 min) and COMT inhibition by tropolone (10(-4) M) in the absence of isoprenaline did not affect cAMP levels. These results suggest that extraneuronally accumulated isoprenaline may inhibit the adenylate cyclase in perfused rat hearts.

[Nocturnal hypoxia and treatment in the patients with Duchenne muscular dystrophy]

Overnight monitoring using pulse oximeter was performed on 10 patients with Duchenne muscular dystrophy (mean age, 22; mean %FVC, 26.6%; mean PaCO2, 54.1 Torr; mean PaO2 76.6 Torr). At the same time, spinal deformity and obesity were examined. In 4 patients, the measurement of the chest and abdominal wall movements were performed by using a respisomnograph. In 5 patients, nocturnal desaturation below 95% occurred despite normal daylight blood gas tension. In the other 5 patients with hypercapnea of over 50 Torr, nocturnal desaturation below 85% occurred, and 3 patients required oxygen supplementation treatment using a low concentration of oxygen. In 4 patients with hypercapnea over 50 Torr, cuirass-assisted respirators were used and they prevented mild nocturnal desaturation, but did not have much effect on severe nocturnal desaturation. Nocturnal desaturation was associated not only with hypopnea and hypoventilation, but with normal chest and abdominal wall movement using cuirass-assisted respirators. It seemed that desaturation with normal respiratory pattern can be attributed to ventilation-perfusion mismatching. The severity of the desaturation did not always correlate to the spinal deformity and the obesity.

Concentrations of ampicillin in human serum and mixed saliva following a single oral administration of lenampicillin, and relationship between serum and mixed saliva concentrations

The concentrations of ampicillin in serum and mixed saliva after a single oral administration of lenampicillin (500 mg) were determined by the paper disc method. The samples of serum and mixed saliva were obtained at 1, 2, 3 and 4 h after administration. The highest concentrations of ampicillin in serum and mixed saliva occurred 1 h after administration of lenampicillin, and were 11.55 and 0.060 micrograms/ml, respectively. A significant correlation coefficient between the concentrations of ampicillin in serum and mixed saliva, r = 0.71, P less than 0.001, was found.

A novel orally active dopamine prodrug TA-870. III. Positive inotropic effect and cardiorenal selectivity in anesthetized dogs

The effect of TA-870, a novel dopamine prodrug, on the cardiovascular system was studied in anesthetized open- and closed-chest dogs. Intraduodenal administration of less than or equal to 12 mg/kg TA-870 to anesthetized dogs increased left ventricular (LV) dP/dtmax and dP/dt/Pmax. Furthermore, at a lower dose of TA-870 (2 mg/kg), renal vascular resistance (RVR) decreased and renal blood flow (RBF) increased. Similarly, total peripheral resistance (TPR) decreased and cardiac output (CO) increased at less than 4 mg/kg. In an intravenous cumulative dose-response study of TA-870, the plasma-free-dopamine concentration was elevated depending on the dose of TA-870. Renal vasodilation occurred at a low plasma-free-dopamine concentration, whereas a positive inotropic action required higher plasma-free-dopamine. However, the dose-response curve for LVdP/dt/Pmax was steeper than that for RBF or CO. Heart rate was less affected than LVdP/dt/Pmax in open-chest dogs and decreased in closed-chest dogs. Propranolol strongly inhibited the effect of TA-870 on LVdP/dt/Pmax. It also inhibited the effects of TA-870 on TPR and CO to a lesser extent, and the remaining effects were almost completely inhibited by an additional treatment with the dopamine blocker, RS-sulpiride. In conclusion, TA-870 increased myocardial contractility and output by the enteral route, and the latter effect was produced at lower doses with the help of peripheral vasodilation due to the activation of dopamine receptors.

Cephalexin concentrations in human serum, gingiva, and mandibular bone following a single oral administration

1. Cephalexin concentrations in human serum, gingiva, and mandibular bone after a single oral administration of cephalexin (500 mg) were measured by the paper disc method. 2. The peak times of serum, gingiva, and mandibular bone were approximately 90, 120 and 120 min, respectively. 3. The peak concentrations of serum, gingiva, and mandibular bone were 10.58 micrograms/ml, 5.57 micrograms/g and 2.12 micrograms/g, respectively. 4. The concentration ratio of gingiva/serum and mandibular bone/serum peak time of serum were 0.47 and 0.18, respectively. 5. Cephalexin concentrations in gingiva and mandibular bond did not exceed the MIC80s for clinically isolated strains of Staphylococcus aureus spp., alpha-Streptococci and Peptostreptococcus spp.

Intracellular accumulation of isoproterenol enhances the lactate production in the perfused rat heart

Effects of intracellular accumulation of isoproterenol (ISO) on lactate production were examined in perfused rat heart. The lactate production during ISO perfusion in rat heart was increased and subsequent addition of an inhibitor of catechol-O-methyl transferase (COMT) further enhanced the production, and the enhanced production was significantly reduced by uptake2 inhibitor. The perfusion with ISO free-medium in the heart with high intracellular accumulation of ISO produced lactate more than that in the low intracellular accumulation. The present experiments demonstrated that the enhanced lactate production is accompanied by intracellular accumulation of ISO in the perfused rat heart, and suggested that the accumulated ISO may activate intracellular beta-adrenoceptors in the rat heart.

[Susceptibility and beta-lactamase-producing strains of methicillin-resistant Staphylococcus aureus]

Thirty-three strains of methicillin-resistant Staphylococcus aureus (MRSA, MIC for methicillin greater than or equal to 16.0 micrograms/ml) isolated from sputum were examined for their susceptibilities against 8 antimicrobial agents. Ampicillin (ABPC), methicillin (DMPPC), cefazolin (CEZ), minocycline (MINO), erythromycin (EM), tobramycin (TOB), refampicin (RFP), and ofloxacin (OFLX) were used as the antimicrobial agents. The production of beta-lactamase was also determined. The results are as follows: 1) The highest susceptibility was given by RFP, and followed by MINO, and OFLX. All strains were resistant against EM and TOB. 2) The percentage of beta-lactamase-positive strains was 75.8%, which was distributed nearly identical among each MIC to DMPPC (72.0-77.8%). 3) Since the beta-lactamase-positive strains were found among the sensitive strains to ABPC, it was suggested that the use of beta-lactam antimicrobial agents might bring into the higher MIC value to ABPC. 4) Since there were beta-lactamase-negative strains among the resistant strains to ABPC, it was indicated that penicillin binding protein-2' might be produced by giving beta-lactam antimicrobial agents.

A novel orally active dopamine prodrug TA-870. II. Evidence that TA-870 is a dopamine prodrug

The mechanism of action of a new orally active dopamine (DA) prodrug, TA-870 (N-(N-acetyl-L-methionyl)-O,O-bis(ethoxycarbonyl)(DA) was studied. When TA-870 (1 mg/kg) was injected in anesthetized dogs, renal vascular resistance was decreased and renal blood flow was increased. The renal vasodilatory effect of TA-870 correlated with the plasma level of DA but not with the level of de-ethoxycarbonyl metabolite of TA-870 (i.e., N-(N-acetyl-L-methionyl)DA; DEC-TA-870). The renal vasodilatory effect of TA-870 was inhibited strongly by haloperidol and slightly by propranolol. Pretreatment with phenoxybenzamine enhanced the renal vasodilatory effect of TA-870. In the isolated rabbit splenic artery, TA-870 and DEC-TA-870 showed no effects, whereas dopamine showed a contracting effect, which was inhibited by phentolamine. In the propranolol- and phentolamine-treated splenic artery, TA-870 and DEC-TA-870 caused weak relaxant effects on PGF2 alpha-induced contraction. These effects were not antagonized by metoclopramide. On the other hand, DA showed a strong relaxant effect, which was competitively inhibited by metoclopramide. In addition, TA-870 and DEC-TA-870 further relaxed the artery that had been maximally relaxed by DA. We concluded that TA-870 and DEC-TA-870 exert weak vasodilatory effects that are different from that of DA in vitro, and that TA-870 exerts its vasodilatory effect after its conversion to free DA in vivo.

A novel orally active dopamine prodrug TA-870. I. Renal and cardiovascular effects and plasma levels of free dopamine in dogs and rats

Intraduodenal administration of N-(N-acetyl-L-methionyl)-O, O-bis(ethoxycarbonyl)dopamine (TA-870), a newly synthesized dopamine derivative, increased the renal blood flow (RBF) and mesenteric blood flow in anesthetized dogs, while blood pressure and heart rate were less affected. It also increased the glomerular filtration rate, urine volume, and urinary sodium excretion in saline-loaded anesthetized dogs. In conscious dogs, TA-870 and dopamine hydrochloride (DA-HCl) increased RBF in parallel with increases in plasma free dopamine (free-DA) concentration. At an equimolar dose of 71 mumols/kg, p.o., the effect of TA-870 continued for greater than 4 h, while that of DA-HCl lasted for only 2 h: the peak free-DA concentration and maximum increase in RBF were 155 +/- 57 ng/ml and 56 +/- 15%, respectively, for TA-870, and those for DA-HCl were 32 +/- 13 ng/ml and 36 +/- 10%. Similarly, TA-870 showed greater increases in both RBF and plasma free-DA concentration than DA-HCl in anesthetized rats. In contrast to enteral administration, intravenously administered TA-870 exhibited weaker effects than intravenous DA-HCl in anesthetized dogs. In conclusion, TA-870 is an orally effective dopamine prodrug capable of producing higher and more sustained plasma concentrations of dopamine than DA-HCl when administered by the enteral route.

Effects of specific alpha-adrenoceptive agents on extraneuronal uptake (uptake2) of isoproterenol in perfused rat heart

Effects of specific alpha-adrenoceptive agents (alpha 1-agonist, alpha 1-antagonist, alpha 2-agonist and alpha 2-antagonist) on the extraneuronal accumulation of 3H-isoproterenol in the perfused rat heart were examined. The extraneuronal accumulation of 3H-isoproterenol in the hearts perfused with 3H-isoproterenol (10(-6)M) under COMT inhibition by tropolone (10(-4)M) was about 6 times higher than that of intact COMT. The increase in the accumulation by COMT inhibition was regarded as 100% and the effects of specific alpha-adrenoceptive agents on the accumulation was evaluated. alpha 1-agonists, methoxamine and phenylephrine, did not affect the accumulation. alpha 1-antagonists, prazosin, bunazosin and YM-12617, significantly decreased the accumulation of 3H-isoproterenol and these IC50 values were 2 x 10(-6)M, 3.5 x 10(-6)M and 2.3 x 10(-5)M, respectively. alpha 2-agonists, clonidine and guanabenz, significantly reduced the accumulation and these IC50 values were 3.4 x 10(-5)M and 2.9 x 10(-7)M, respectively. The alpha 2-antagonist, yohimbine, did not affect the accumulation. The present experiments clearly demonstrated that the tested alpha 1-antagonists and alpha 2-agonists inhibited uptake2 in rat heart but the tested alpha 1-agonists and an alpha 2-antagonist did not inhibit it.

Josamycin concentrations in human dental granuloma after a single oral administration of josamycin

1. Josamycin concentrations in human serum and dental granuloma after a single oral administration of josamycin (600 mg) were assayed by an agar diffusion (paper disc) method. 2. The mean peak josamycin concentrations in serum and dental granuloma occurred at an identical time, approximately 90 min, and were 0.88 micrograms/ml and 1.61 micrograms/g, respectively. 3. The mean concentration ratio of dental granuloma to serum at the peak time was 2.24. 4. Josamycin concentration in dental granuloma at the peak time exceeded MIC80 for clinically isolated strains of Streptococcus group A, Peptostreptococcus spp., and Bacteroides spp.

Epidermal growth factor (EGF)-induced morphological changes in the basement membrane of chick embryonic skin. An electron-microscopic study

The effect of epidermal growth factor (EGF) on the basement membrane structure of chick embryonic skin cultured in a chemically defined medium (BGJb) containing 20 mM hydrocortisone, and EGF at 10, 50, or 100 ng/ml supplemented with 5% delipidized fetal calf serum, was examined by electron microscopy. During development of the epidermis in vitro, EGF (100 ng/ml) caused striking changes to occur in the basement membrane structure and in the keratinization process. The basement membrane frequently became discontinuous with many gaps apparent in section, and occasionally became folded following detachment from the basal surface of the epidermis and protruded into the underlying dermis. In the basal and intermediate cells of EGF-treated epidermis, tonofilament bundles were decreased in number, while desmosomes and hemidesmosomes revealed no significant changes in morphology.

Effects of NC-1300-B, a new benzimidazole derivative, on hog gastric H+, K+-ATPase, gastric acid secretion and HCl.ethanol-induced gastric lesions in rats

This study was designed to determine the effect of a newly synthesized benzimidazole derivative NC-1300-B on H+, K+-ATPase (proton pump) in the hog gastric mucosa and on the basal gastric acid secretion and necrotizing agent-induced gastric lesions in rats. NC-1300-B inhibited the proton pump in a concentration-dependent manner and concentrations which inhibited the enzyme activity by 50% were 4.4 x 10(-6) M at pH 6.0 and 3.1 x 10(-5) M at pH 7.4. NC-1300-B administered orally or intraperitoneally 0.5 hr before ligating the pylorus inhibited the gastric acid secretion in a dose-dependent manner. The ED50 values (doses which inhibit acid output or lesion formation by 50%) for acid secretion were 11.5 and 11.0 mg/kg with oral and intraperitoneal administration, respectively. The antisecretory effect in a dose of 100 mg/kg persisted for up to 72 hr. NC-1300-B administered orally or intraperitoneally 0.5 hr before HCl.ethanol administration protected against damage of the gastric mucosa in a dose-dependent manner. The ED50 values for lesion formation were 13.3 and 23.0 mg/kg with oral and intraperitoneal administration, respectively. This protection with an oral dose of 100 mg/kg persisted for up to 72 hr. While pretreatment with 5 mg/kg of indomethacin given subcutaneously did not appreciably reverse the NC-1300-B protection, the pretreatment with 10 mg/kg of N-ethylmaleimide given subcutaneously potently reversed the NC-1300-B protection. NC-1300-B administered intragastrically at 30 mg/kg significantly inhibited the amplitude of gastric contraction for 50 min after intragastric administration. These effects of NC-1300-B on gastric secretion and lesion formation are much the same as those of the established proton pump inhibitor omeprazole, except for the short duration of the action of omeprazole (less than 24 hr).

Response of the mouse femoral muscle to an implant of a composite of bone morphogenetic protein and plaster of Paris

A composite consisting of 1 mg of bone morphogenetic protein (BMP) and 5 mg of plaster of Paris (PLP) was implanted into the mouse femoral muscle. Control PLP without BMP was implanted into the contralateral muscle. The BMP/PLP composite induced cartilage formation within two weeks, trabecular bone within three weeks, and lamellar bone including bone marrow within six weeks. PLP did not disturb BMP-induced bone formation. In addition, the BMP/PLP composite was resorbed early after implantation. These results suggest that PLP composite system is one of the most suitable BMP delivery systems currently available.