Pharmacological profiles of the subtypes of muscarinic cholinoceptors that mediate aggregation of pigment in the melanophores of two species of catfish

Using selective antagonists, including pirenzepine, adiphenine, AF-DX 116, gallamine, and 4-DAMP, we attempted to characterize the muscarinic cholinoceptors on the melanophores of the translucent glass catfish Kryptopterus bicirrhis and the mailed catfish Corydoras paleatus. The M3 receptor-selective antagonist, 4-DAMP, potently inhibited the acetylcholine-induced aggregation of pigment in both species. It appeared, therefore, that the receptors that mediated the cholinergically evoked aggregation of melanosomes in these species were of the M3 muscarinic subtype.

Effect of newly synthesized indole derivatives on multidrug resistance in human cancer cells

Twenty indole derivatives were investigated for their ability to reverse multidrug resistance (MDR), for their ability to compete with [3H]azidopine in binding to P-glycoprotein (P-gp) and for their hydrophobicity. Six derivatives almost completely reversed the resistance to vincristine (VCR) in multidrug-resistant KB-C2 cells, and other derivatives partially overcame the resistance. The ability of the derivatives to enhance vincristine cytotoxicity did not significantly correlate with the inhibition of [3H]azidopine binding to P-gp or with their hydrophobicity. However, all the derivatives that inhibited > 50% of the photolabeling completely reversed VCR resistance. The 2-pyridyl group with a basic nitrogen atom attached at position 3 of indole in an appropriate spatial orientation seems to be an important feature for the interaction of the indole derivatives with P-gp. One of the derivatives, 1, which has low cytotoxicity and hydrophobicity, completely reversed the resistance of KB-C2 cells to Adriamycin, actinomycin D and VCR. Our data indicate that MDR-reversing indole derivatives with low cytotoxicity and hydrophobicity exist. These characteristics will surely be profitable for clinical use.

[Pharmacokinetic and clinical studies with L-627 (biapenem) in the pediatric field. Pediatric study group of L-627]

To conduct pharmacokinetic and clinical studies on newly developed L-627 (biapenem) against various infections in pediatrics, a study group was organized and a joint research by 15 institutions and their related hospitals was undertaken. Informed consents of subjects were obtained prior to the study. The obtained results are as follows. 1. Plasma concentrations and urinary excretion Pharmacokinetics of L-627 in children was studied in 29 subjects using 30 minutes intravenous drip infusion of 6 mg/kg and 12 mg/kg. Maximum plasma levels of L-627 was observed at the completion of drip infusion and were 25.1 micrograms/ml with administration of 6 mg/kg and 39.2 micrograms/ml with administration of 12 mg/kg on average. Dose dependency was noted in Cmax and AUC with these doses. Maximum blood levels in all of the 5 participated sucklings under the age of one year were similar to the average. As for urinary excretion, L-627 was excreted 66.0% with administration of 5 mg/kg and 62.3% with 12 mg/kg. 2. Cerebrospinal fluid concentrations Cerebrospinal fluid concentrations ranged from 0.76 to 8.54 micrograms/ml in 30-240 minutes after the completion of drip infusion with dose of 20-40 mg/kg in 9 subjects with purulent meningitis, when they were measured within 3 days after the initiation of the treatment with L-627. 3. Clinical results Thirty-three cases of exclusion and drop-out were deducted from a total of 330 cases, hence 297 cases were evaluated as the subjects in the study for analysis of clinical effects. As for clinical effects in group A where pathogenic bacteria were detected, 166 out of 173 were rated as effective or above, hence the efficacy rate of 96.0% was obtained. In group B where pathogenic bacteria were not detected, 114 out of 124 cases were rated as effective or above, thus the efficacy rate was 91.9%, which is similar to that of the group A. The overall efficacy rate was 94.3% in the entire 297 cases. The rates of "excellent" responses out of the cases rated as effective or above were 62.7% (104/166) in the group A and 55.3% (63/114) in the group B, thus the rate was markedly high in the former group. Efficacy rate for each pathogenic strain was also high, and that in subjects infected by a single pathogenic strain was 96.7% (145/150) and that in subjects infected by two or more pathogenic strains was 91.3% (21/23).(ABSTRACT TRUNCATED AT 400 WORDS)

[Pharmacokinetic and clinical studies of SY5555 in the pediatric field. Pediatric Study Group of SY5555]

SY5555, a new oral penem, was pharmacokinetically and clinically evaluated in the pediatric field and the following results were obtained: 1. Pharmacokinetics Pharmacokinetics of SY5555 dry syrup (powder which is dissolved before use) was investigated in 64 children. At a dose level of 3 mg (potency)/kg, Cmax and T1/2 were 0.33 micrograms/ml and 0.95 hours (n = 1), respectively, in the non-fasting state. At a dose level of 5 mg/kg Cmax and T1/2 were 2.09 +/- 1.25 micrograms/ml and 1.20 +/- 1.07 hours, respectively, in the fasting state, and were 1.21 +/- 0.70 micrograms/ml and 1.33 +/- 0.90 hours, respectively, in the non-fasting state. At a dose level of 10 mg/kg, Cmax and T1/2 were 2.96 +/- 1.89 micrograms/ml and 0.89 +/- 0.43 hours, respectively, in the fasting state, and were 2.45 +/- 1.37 micrograms/ml and 1.17 +/- 0.53 hours, respectively, in the non-fasting state. At a dose level of 15 mg/kg, Cmax and T1/2 were 4.30 +/- 2.15 micrograms/ml and 0.82 +/- 0.09 hours, respectively, in the non-fasting state. Data of Cmax and AUC showed that plasma concentration of the drug depended on dose levels. Urinary recovery rates in the first 6 hours were 1.71% (n = 1) in the non-fasting state at a dose level of 3 mg/kg, 4.13 +/- 1.40% in the fasting state and 4.17 +/- 3.29% in the fasting and the non-fasting state, respectively at a dose level of 5 mg/kg, and 6.02% (n = 1) and 4.64 +/- 2.81%, respectively, at a dose level of 10 mg/kg. At a dose level of 15 mg/kg, urinary recovery rate in the first 6 hours was 7.97% (n = 2) in the non-fasting state. 2. Clinical results 1) Dry syrup The clinical efficacy of the SY5555 dry syrup was evaluated in 506 cases. SY5555 was administered at daily doses of 15-30 mg/kg divided into 3 equal doses to most patients. Daily doses of 12- < 18 mg/kg were given to 46.6% of the patients. The overall clinical efficacy rate was 92.9%, and this drug was effective in 93.0% of the 301 patients for whom the causative pathogens were identified, and in 92.7% of the 205 patients with infections for whom the causative pathogens were unknown. The efficacy rate at daily doses of 12 - < 18 mg/kg was 94.5% similar to those obtained at daily doses of 18- < 27 mg/kg (91.7%) or 27- < 33 mg/kg (91.3%). The bacteriological eradication rate was 82.3%.(ABSTRACT TRUNCATED AT 400 WORDS)

Active efflux system for cisplatin in cisplatin-resistant human KB cells

Mutants, KCP-4 and PC-5, resistant to an anticancer agent, cisplatin, were selected in multiple steps from human epidermoid KB carcinoma cells and human prostate PC-3 carcinoma cells, respectively. KCP-4 and PC-5 were 63 and 10 fold more resistant to cisplatin than the parental cells, respectively. KCP-4 cells exhibited increased resistance to cisplatin analogues and were also slightly cross-resistant to melphalan, cyclophosphamide, mitomycin C and methotrexate. KCP-4 cells were not cross-resistant to doxorubicin, daunorubicin, vincristine or CdSO4. The accumulations of cisplatin in KCP-4 cells and PC-5 in medium containing 50 microM cisplatin were approximately 20% of those in the parental cells. Revertant analysis suggested that a defect in cisplatin accumulation may be related to cisplatin resistance in PC-5 cells. The uncoupling agent of oxidative phosphorylation, 2,4-dinitrophenol, increased the accumulation of cisplatin in KCP-4 and cisplatin-resistant human prostate carcinoma PC-5 cells to nearly the same level as in their parental KB-3-1 and human prostate carcinoma PC-3 cells without 2,4-dinitrophenol, but did not increase accumulation in KB-3-1 and PC-3 cells. Addition of glucose in the medium inhibited the enhancement of cisplatin accumulation in KCP-4 cells by 2,4-dinitrophenol. Enhanced active efflux of cisplatin from KCP-4 cells was observed. A cell-cell hybridization test showed that the cisplatin resistance and the accumulation defect behaved as codominant traits. These data suggest that an active efflux system for cisplatin exists in cisplatin-resistant KCP-4 cells.

[Cardiac vagal withdrawal during stressful tasks estimated by the baroreflex sensitivity and respiratory sinus arrhythmia]

The primary purpose of this study was to compare the changes in baroreflex sensitivity (BRS) with those in respiratory sinus arrhythmia (RSA) during mental arithmetic (MA) and reaction time (RT) tasks. BRS was assessed by the sequence scanning method (Bertinieri et al., 1988) combined with the vascular unloading technique that enables beat-by-beat measurement in systolic blood pressure. Twenty-eight male college students were given both MA and RT tasks with the order counterbalanced. Results indicated significant differences in BRS and RSA reactivity that seems to be evidence for a stronger vagal withdrawal in MA. Reactivity in RSA was correlated more closely with respiratory variables (respiration rate, tidal volume, and end-tidal CO2) than in BRS. These findings suggest that BRS is more suitable for estimating cardiac parasympathetic control because of its greater independence from respiratory activity. The results were discussed concerning the patterning of cardiorespiratory stress responses.

[A hemodynamic comparison of cardiovascular stress responses during mental arithmetic and reaction time tasks]

The primary purpose of this study was to examine the covariation between preload (PL) and other cardiovascular stress responses during mental arithmetic (MA) and reaction time (RT) tasks. PL, stroke volume (SV), cardiac output (CO) and pre-ejection period (PEP) were obtained using impedance cardiography. Mean blood pressure (MBP) was measured by the vascular unloading method. Thirty-one male college students were given both MA and RT tasks with a counterbalanced order. Results indicated significant differences in heart rate reactivity which seems to provide evidence for a stronger vagal withdrawal in MA. Changes in CO and MBP were identical in these two tasks which might have resulted from a compensatory change in PL and SV. Specificity of PEP for the increased beta-adrenergic activity was supported by the correlation pattern among PL, MBP and PEP. The results were discussed in the context of cardiovascular regulating mechanisms.

[Clinical studies of arbekacin sulfate in the pediatric field]

A clinical investigation was carried out to evaluate arbekacin, an aminoglycoside, in the treatment of MRSA infections (pneumonia, septicemia, etc.) of pediatric patients. The obtained results are summarized as follows. 1.

CLINICAL RESULTS

Excluding those patients who met the present exclusion criteria and withdrawal cases from a total of 18 patients, 10 patients (3, 6, and 1 cases of septicemia, pneumonia, and urinary tract infection, respectively) were subjected to clinical evaluation. These were composed of 1, 1, 6, and 2 cases of neonate, infants, pre- and school age children, respectively. Excellent, good and fair results were obtained in 5, 2, and 3 patients, respectively; thus, the efficacy rate was 70.0%. The efficacy rate by disease was 100%, 50.0% and 100% in septicemia, pneumonia, and urinary tract infection, respectively. The bacteriological eradication were obtained in 70.0% of the total patients; by disease, these rates were 100% and 50.0% in septicemia/urinary tract infection and in pneumonia, respectively. The MIC50 as well as the MIC80 against MRSA strains isolated from 9 patients were 0.39 microgram/ml and 1.56 micrograms/ml, respectively. No adverse reactions were observed in the 15 patients, while in laboratory test values, one case each out of 12 patients examined showed gamma-GTP elevation, proteinuria, and hematuria. 2. Pharmacokinetics: The pharmacokinetics of the agent was investigated in a total of 9 patients, which included 1 neonate and 4 cases each of pre- and school age children. The Cmax, 4.85-8.83 micrograms/ml, was observed immediately after the termination of the instillation. The T1/2's were 4.96 hours, 1.24-2.54 hours, and 1.78-1.88 hours in the neonate, the pre- and the school age children, respectively; in the neonate the half-life was longer. When 1.92-2.7 mg/kg were administered to 3 each of the pre- and school age children, urinary excretion rates in the first 6-8 hours were 40.1-56.5% of the dosages administered. In all cases, the urinary concentrations were highest in the first 2 hours, after the administration, and then gradually decreased. These results suggest that arbekacin is a useful antibiotic for treating MRSA infections in the pediatric field.

[Pharmacokinetic and clinical studies with cefozopran in the pediatric field. Pediatric Study Group of Cefozopran]

We investigated pharmacokinetics and clinical effectiveness of a newly developed cephem antibiotic cefozopran (SCE-2787, CZOP) against various pediatric infections in 18 institutions and their affiliates. We obtained the following results. 1. Serum concentration and urinary excretion rates Pharmacokinetics of CZOP in children was examined after intravenous injection and 30-minute drip infusion of 10, 20 and 40 mg/kg of CZOP. Peak serum concentrations of CZOP in 30 minutes after intravenous injection were 21.7, 51.5 and 77.8 micrograms/ml, respectively, showing a clear dose response. Half-lives were 1.99, 1.85 and 1.67 hours, respectively. In the first 6 hours after administration, urinary excretion rates of CZOP were 87.3, 67.4 and 84.1%, respectively. In the cases of 10, 20 and 40 mg/kg administration of CZOP 30-minute drip infusion, peak serum concentration of CZOP in 30 minutes, when the infusion was completed, were 38.1, 72.8 and 95.6 micrograms/ml, respectively. Again, there was a clear dose response. Half-lives were 1.67, 1.69 and 1.43 hours, respectively. In the first 6 hours after administration, urinary excretion rates of CZOP were 53.9, 59.7 and 77.3%, respectively. Cerebrospinal fluid concentrations of CZOP administered by intravenous injection of 50 mg/kg to patients with purulent meningitis were 1.6 to 43.4 micrograms/ml in 1 to 1.5 hours after administration. 2. Clinical study Clinical efficacy was evaluated in 337 cases. The largest number of cases, 138 cases, were found in 2 to < 6-year olds. The majority of the patients were under age 9, and 70 cases were of less than 1-year old infants. 183 cases were males and 154 cases were females. In terms of illness, a majority, or 185 cases, suffered from pneumonia, followed by 39 cases of UTI and 23 infections of the skin and soft tissue. There were 7 cases of purulent meningitis. In 218 cases, CZOP was administered at a daily dose of 60- < 80 mg/kg. The drug was administered for 6-10 days, the most frequent duration, in 188 cases. In the cases where causative organisms were identified (group A), the efficacy rates ("excellent" and "good") obtained were 100% (5/5) against purulent meningitis, 100% (2/2) against sepsis, 98.3% (119/121) against pneumonia, 100% (13/13) against acute bronchitis, 100% (11/11) against upper respiratory tract infection, 96.3% (26/27) against UTI. Overall, "excellent" and "good" responses were observed in 97.5% (197/202) of cases with known causative organisms.(ABSTRACT TRUNCATED AT 400 WORDS)

[Clinical evaluation of S-1108 in children]

A new oral cephem antibiotic, S-1108, was evaluated for its clinical efficacy and safety in children. S-1108 was effective in 95% of the 59 examined cases of respiratory, middle ear, skin and urinary tract infections. S-1108 was highly effective in infections of Streptococcus pyogenes, Haemophilus influenzae and Escherichia coli, but was less effective in penicillin-resistant Streptococcus pneumoniae and Staphylococcus aureus infections. The serum half-life was 1.26 +/- 0.36 hours upon after meal administration of 4 mg/kg. No severe adverse reaction was encountered. From these data, S-1108 appears to be safe and effective in children with susceptible bacterial infections.

[Nonfunctioning pituitary tumor--subunit, inactive hormone producing tumor]

Approximately 25-30% of the patients with pituitary adenomas were clinically non-functioning adenoma. Recent studies, using molecular biology techniques combined with culture of removed tumors, have revealed that most of these tumors synthesize glycoprotein hormones and/or their subunits. Recent progress and current diagnostic issues are discussed.

[Effect of cefditoren pivoxil on carnitine metabolism in pediatric patients]

Carnitine metabolism was studied in 16 pediatric patients with various infections under the treatment with cefditoren pivoxil (CDTR-PI) in granular form. Pivalic acid released from pivaloyloxymethyl ester of the drug was metabolized to pivaloylcarnitine. As results, an increase in urinary carnitine excretion (predominantly as pivaloylcarnitine) and, a decrease in free carnitine concentration and a high acyl/free carnitine ratio in serum (plasma) were observed during the treatment. When the dosing was terminated, pivaloylcarnitine in plasma and then in urine disappeared, and the concentration of free carnitine, acyl/free carnitine ratio returned to the normal range. No carnitine-related side effects were observed throughout the study.

Molecular cloning and sequence analysis of the crtB gene of Thermus thermophilus HB27, an extreme thermophile producing carotenoid pigments

We have cloned and sequenced a 1.5-kb chromosomal fragment of Thermus thermophilus which promoted the overproduction of carotenoids in T. thermophilus. An open reading frame (ORF-A) coding for a polypeptide with 289 amino acids was responsible for carotenoid overproduction. The putative ORF-A protein showed significant homology with the amino acid sequences of crtB gene products (phytoene syntheses) of other microorganisms. The clone containing the ORF-A on a multicopy plasmid produced about three times as much carotenoid as that produced by the host strain, suggesting that the crtB gene product is a rate-limiting enzyme for carotenoid biosynthesis in T. thermophilus.

Phosphoinositide turnover imaging linked to muscarinic cholinergic receptor in the central nervous system by positron emission tomography

Receptor-mediated membrane processing plays an essential role in neural function in the synapses. In such neurotransmission process, the phosphoinositide (PI) response, an effector in the production of second-messengers, can be used to assess in vivo signal transduction. Using in vivo autoradiography and positron emission tomography (PET), we attempted to visualize the PI response to muscarinic cholinergic receptor (mAChR)-stimulation in rats and monkeys, which were administered 1,2-[11C]diacylglycerol (DAG) intravenously. Enhancement of 1,2-[11C]DAG incorporation was observed in the rat ipsilateral hippocampus and cortex in which mAChR-agonist was administered by local injection, but this was in contrast to spreading cortical depression in the ipsilateral cortex using KCl. In monkey PET studies, dynamic brain scanning revealed increase in activity over time for about 15 min after a bolus injection of 1,2-[11C]DAG in an awake state. The activity then remained at a constant level. This finding documented the theoretical "membrane-trapping" mechanism. The systemic mAChR-stimulation accelerated incorporation in the cerebral cortices of the same monkey brain. Radioactivity uptake did not differ significantly between the mAChR-stimulated and nonstimulated early scan images. This suggested that cerebral blood flow does not greatly affect DAG incorporation. In sequential membrane processes of PI turnover, diacylglycerol kinase rapidly metabolizes DAG, included in PI turnover. In conclusion 1,2-[11C]DAG incorporation was limited by receptor-mediated PI turnover, which can represent real synaptic transmission in neural networks.

[A clinical study of fluconazole-granules and -injectable in pediatric patients with deep-seated mycoses]

Fluconazole (FLCZ) is an antifungal agent of triazole class developed by Pfizer, Inc. Its oral and injectable forms have been available on the market since June 1989 in Japan. FLCZ exhibits potent antifungal activities against Candida spp., Aspergillus spp. and Cryptococcus spp. and, as orally or intravenously administered, is widely distributed into organs and tissues. For its low protein binding rate of about 10 per cent and long serum half life of about thirty hours in adults, FLCZ has been proved highly effective and useful in the treatment of deep-seated mycosis in adult patients. In the present study, we have investigated the clinical effectiveness and antifungal activities of FLCZ granules, a new dosage form of the drug, and of intravenous form in pediatric patients with deep mycosis. A total of 72 patients were treated either with granules orally or with intravenous injection and 47 patients among them were evaluable on the clinical efficacy of the drug. Also, a study on the pharmacokinetics of pediatric patients including premature/new born babies was conducted employing multiple dose regimens in a total of 27 patients. The clinical efficacy rates were 79.5% (35 patients out of 44) in candidiasis and 100.0% (3 of 3) in aspergillosis. The safety of the drug was assessed in 63 patients. No side effects were observed. Clinical laboratory test abnormalities were observed in some patients with an incidence of 9.7% (6 patients out of 62) but most of the abnormalities were only mild and transient. The pharmacokinetics at repeated doses indicated that a steady-state is reached in 4 days after the initial administration of either granules or intravenous form. From these results, it may be concluded that FLCZ is a very useful medication in the treatment of deep mycosis in pediatric patients.

[Criteria for clinical evaluation of antibiotics in pediatrics. The purpose and process for establishing the criteria]

This paper describes the purpose and process for establishing "Criteria for Clinical Evaluation of Antibiotics in the Pediatric Field", which was reported in the Japanese Journal of Antibiotics Vol. 46, May, 1993. The Criteria Committee was organized in November 1991. Four meetings were held to establish the draft criteria. The criteria were applied to the evaluation of oral cephem S-1108 and parenteral cephem SCE-2787. When the criteria were compared with the conventional criteria, the results indicated that no difference was obtained in the efficacy rate as a whole, the sum of "Good" and "Excellent" cases, but there was a difference in the cases judged to be "Excellent". Partial alteration was made to the draft criteria and the Committee produced the final version of the criteria. However, the criteria are far from complete, so it will be subjected to further revision it accordance with future advance in chemotherapy.

[Pharmacokinetics and clinical studies on flomoxef in neonates and premature infants. A study of flomoxef in the perinatal collaboration research group]

We investigated pharmacokinetics and clinical effects of flomoxef sodium (6315-S, FMOX) in neonates and premature infants. These results are summarized as follows: 1. Pharmacokinetics (1) Plasma concentration (Ct) and half-lives (T1/2) were determined upon after intravenous one-shot injection (i.v.) of FMOX to neonates of different day-age groups (0-3 (n = 25), 4-7 (n = 18), 8-28 (n = 32) days of birth). At a dose of 10 mg/kg. i.v., mean C30 (30 minutes concentration) values were 21.2, 21.8 and 21.3 micrograms/ml, respectively, in the different groups mentioned above, and the mean T1/2 values were 3.37, 1.85 and 1.63 hours. At 20 mg/kg i.v., mean C15 (15 minutes concentration) values were 54.4, 51.4 and 50.7 micrograms/ml, and mean T1/2's were 2.99, 2.32 and 1.79 hours, respectively. At a dose of 40 mg/kg i.v., mean C15 values were 104.0, 95.9 and 99.2 micrograms/ml, and the mean T1/2's were 3.40, 1.20 and 1.80 hours, respectively. (2) Plasma concentrations and T1/2 after intravenous one-shot injection of FMOX in premature infants in group (0-3 (n = 14), 4-7 (n = 10), 8-28 (n = 13) days of birth). Mean C15's at doses of 10, 20 and 40 mg/kg in the different groups of infants were 24.0, 28.6, 21.7 and 54.0, 54.6, 55.5 and 98.2, 93.0, 106.0 micrograms/ml, and T1/2's were 4.10, 2.53, 2.57 and 4.28, 2.27, 3.02 and 4.66, 2.86, 2.09 hours, respectively. Mean Cmax values were clearly dose dependent, and mean T1/2 values tended to be longer in premature infants compared to neonates. (3) Urinary recovery rate of FMOX after intravenous injection in neonates and premature infants. Mean urinary recovery rates of FMOX in the first 6 hours after i.v. (one-shot) at doses of 10, 20 and 40 mg/kg to neonates and premature infants were 38.9-62.8% in the neonates and 30.7-61.5% in the premature infants. (4) Plasma concentrations and urinary recovery rates upon 1 hour drip infusion of 20 mg/kg in the neonate groups (or the premature infant groups) as follows: Mean C50 values were 31.0, 32.7 and 23.4 micrograms/ml, and T1/2 were 2.94, 3.68 and 2.25 hours, respectively. The recovery rates were 35.2-52.9% in the first 6 hours after administration. 2. Clinical studies The number of clinically evaluable cases in the FMOX treatment of premature infants was 199, in which the causative pathogens were identified in 71 cases (A group) and not identified in 128 cases (B group).(ABSTRACT TRUNCATED AT 400 WORDS)

[A clinical study on cefditoren pivoxil granules in the pediatric field]

The clinical efficacy of cefditoren pivoxil (CDTR-PI, ME 1207) was evaluated in 45 patients with various infections. CDTR-PI was administered after meals at a dose of 3 mg/kg t.i.d. to most patients. The clinical efficacy rate was 95.3%. As side effects, diarrhea occurred in 2 patients. Cefditoren showed excellent antibacterial activities against Haemophilus influenzae, Streptococcus pyogenes and Streptococcus pneumoniae, and was more effective against Staphylococcus aureus than other cephems.

Rapid detection of human group C rotaviruses by reverse passive hemagglutination and latex agglutination tests using monoclonal antibodies

Reverse passive hemagglutination (RPHA) tests and a latex agglutination test with monoclonal antibodies (MAbs) were developed for the rapid detection of noncultivatable human group C rotaviruses. For RPHA tests, two MAbs, MAb 5A12 recognizing the outer capsid and MAb 13A3 recognizing the inner capsid, were separately used for the coating of sheep erythrocytes (SRBCs). Forty-six fecal samples were examined to confirm the practicality of the tests. As a result, there was concordance between the RPHA test with SRBCs coated with MAb 5A12 and polyacrylamide gel electrophoresis of viral RNA (RNA-PAGE) in 44 (95.6%) of 46 samples, while the diagnoses by the RPHA test with SRBCs coated with MAb 13A3 were in complete agreement with those by RNA-PAGE. Furthermore, a latex agglutination test with MAb 13A3 was also developed, and this test was fast enough and sensitive enough to successfully detect the viruses from most fecal samples within 2 min. The present procedures would be useful for the diagnosis of human group C rotavirus infections in clinical laboratories which are not well equipped.

Protein kinase C imaging using carbon-11-labeled phorbol esters: 12-deoxyphorbol 13-isobutyrate-20-[1-11C]butyrate as the potential ligand for positron emission tomography

Protein kinase C plays a crucial role in signal transduction for a variety of biologically active substances which activates cellular functions and their proliferation. The actions are closely related to both normal and abnormal functions in the nervous system. Tumor-promoting phorbol esters can substitute for diacylglycerols which are important ligands that bind to protein kinase C. Three typical phorbol esters, phorbol 13-[1-11C]butyrate, phorbol 12,13-[1-11C]dibutyrate and 12-deoxyphorbol 13-isobutyrate-20-[1-11C]butyrate, were synthesized by using [11C]ethylketene with a high specific activity (186GBq/mumol). Their in vivo autoradiograms demonstrated a heterogenous distribution in rat brain. 12-deoxyphorbol 13-isobutyrate-20-[1-11C]butyrate was particularly suited for in vivo use due to its nontumor-promoting activity and its ready permeability to the blood-brain barrier. High optical density was observed in the cortex, amygdala and hippocampus. The in vivo binding properties of this compound to protein kinase C were confirmed by in vivo displacement studies with unlabeled 12-deoxyphorbol 13-isobutyrate-20-butyrate and unlabeled phorbol 12,13-dibutyrate. This suggests that 12-deoxyphorbol 13-isobutyrate-20-[1-11C] butyrate has a specific binding affinity for protein kinase C.

Muscarinic cholinoceptors that mediate pigment aggregation are present in the melanophores of cyprinids (Zacco spp.)

Like melanophores of many teleosts, those of the dark chub, Zacco temmincki, and the common minnow, Z. platypus (Cyprinidae, Cypriniformes) responded to norepinephrine (NE) by the aggregation of pigment. It was further found that some melanophores were responsive to acetylcholine (ACh) in the same way. The response to NE was blocked by an alpha-adrenergic blocker, phentolamine, whereas the response to ACh was not. By contrast, two muscarinic cholinoceptor antagonists, namely, atropine and scopolamine, effectively blocked the action of ACh. The pigment aggregation due to the liberated sympathetic neurotransmitter was blocked by phentolamine but not by cholinergic blockers. These results suggest that, although the melanophores of these species are controlled in an orthodox manner by the sympathetic nervous system, some of them possess extra muscarinic cholinoceptors that also mediate the aggregation of pigment. The present report is the first to describe the presence of cholinoceptors on the chromatophores in species of fish other than those that belong to the order Siluriformes. The evolutionary implications of these findings are discussed.

Circadian motile activity of erythrophores in the red abdominal skin of tetra fishes and its possible significance in chromatic adaptation

The red abdominal skin of the neon tetra Paracheirodon innesi and the cardinal tetra P. axelrodi was found to blanch at night or in the dark. Melatonin added to the bathing medium caused blanching of the red skin. Microscopic observations of the erythrophores indicated that the erythrosomes aggregated in response to norepinephrine, melanin-concentrating hormone (MCH), and melatonin. Of these compounds, melatonin was the most effective. By contrast, many erythrophores were refractory to MCH. Alpha-melanophore-stimulating hormone, isoproterenol, adenosine, and ATP each caused dispersal of the pigment to some extent. Isoproterenol dispersed the pigment only when an alpha-adrenergic blocker, tolazoline, was present. It appears that the change in color of the abdominal skin is primarily due to increased secretion during the night of the pineal hormone melatonin, while other hormonal and nervous factors may modify the distribution of the pigment in the erythrophores.

[Pharmacokinetic and clinical studies of cefditoren pivoxil in the pediatric field. Pediatric Study Group of ME1207]

Cefditoren pivoxil (ME1207) in granules, a new oral cephalosporin, was pharmacokinetically and clinically evaluated in the pediatric field and the following results were obtained: 1. Pharmacokinetics In infants administered single oral doses of 3 mg (potency)/kg and 6 mg/kg, the Cmax was 1.54 +/- 0.68 and 2.85 +/- 1.03 micrograms/ml; Tmax, 2.27 +/- 1.08 and 2.06 +/- 1.16 hours; T 1/2, 2.22 +/- 1.95 and 1.68 +/- 0.66 hours; and AUC (0-infinity), 7.43 +/- 3.68 and 11.90 +/- 4.51 micrograms.hr/ml, respectively. These values have indicated that the drug has a dose-dependent pharmacokinetic behavior. Urinary concentrations peaked in 2-4 hours after administration. Urinary recovery rates in the first 8 hours were 19.4 +/- 6.6% at 3 mg/kg and 17.1 +/- 5.2% at 6 mg/kg. 2. Clinical results The clinical efficacy of the drug was evaluated in 445 patients with various infections. Cefditoren pivoxil was administered at daily doses of 9-18 mg/kg divided into 3 equal doses to most patients. Daily doses of > 7.5-10.5 mg/kg were given to 48.8% of the patients. The overall clinical efficacy rate was 97.3%, and this drug was effective in 97.5% of the 319 patients for whom the causative pathogens were identified and in 96.8% of the 126 patients with infections for whom the causative pathogens were unknown. The efficacy rate at daily doses of > 7.5-10.5 mg/kg was 97.2%, similar to that obtained at daily doses of > 10.5-19.5 mg/kg (97.0%). The bacteriological eradication rate was 90.4%. The efficacy and eradication rates for 66 patients who had not responded to previous chemotherapy were 95.5% (63/66) and 89.4%, respectively. Side effects occurred in 19 (4.2%) of 456 patients subjected to safety analyses. The primary side effect was diarrhea but no serious side effects were noted. As abnormal laboratory test results, moderate increases of the eosinophils and platelets counts as well as moderate elevations of the transaminases were observed. These abnormalities are also seen with other cephems and to a similar extent. No particular and serious problems were associated with administration of this drug. Based on the above results, cefditoren pivoxil is considered to be very useful at a dose level of 3 mg/kg t.i.d. against most infections encountered in the pediatric field.