[Discrimination between fructus Foeniculi and fructus Anethi by cellulose acetate membrane electrophoresis]

The discrimination between Fructus Foeniculi and Fructus Anethi was studied by cellulose acetate membrane electrophoretic method. The two drugs can be easily distinguished from each other in terms of the band number and colour of the electrophoretograms of the water soluble proteins.

Biological monitoring of dichloropropene: air concentrations, urinary metabolite, and renal enzyme excretion

Fifteen applicators of dichloropropene (DCP) were studied for personal air exposure to DCP, excretion of the metabolite of DCP (3CNAC), and excretion of the renal tubular enzyme, N-acetyl glucosaminidase (NAG). Each was studied for four 6-8 h consecutive intervals following baseline determinations of 3CNAC and NAG excretion. In accord with pilot data, 24-h urinary excretion of 3CNAC (mg) correlated well with exposure product for DCP (min exposed.mg/m3), r = 0.854, p less than .001. A more precise correlation of the air exposure product with urinary excretion of 3CNAC was discerned by using the morning urine after the previous day of exposure (micrograms/mg of creatinine), r = 0.914, p less than .001. Four workers had clinically elevated activity of NAG (greater than 4 mU/mg creatinine) in any of their urine collections after baseline. Nine workers showed greater than 25% increases in NAG excretion when compared to baseline. Dichloropropene air exposure products of greater than 700 mg.min/m3 or excretion of greater than 1.5 mg 3CNAC/d distinguished abnormally high daily excretion of NAG. These data demonstrate a firm positive relationship between air exposure and internal exposure, and a possible subclinical nephrotoxic effect in DCP workers.

Two types of calcium channels in isolated smooth muscle cells from rat tail artery

Whole cell patch-clamp recordings were carried out on smooth muscle cells from rat tail artery in short-term culture to verify the existence of and to characterize the calcium channels that are present. Two types of voltage-dependent calcium channels were identified in 55 of 63 cells studied. The T-type calcium channel was activated at -50 mV, and the peak inward current occurred at -10 mV, whereas the L-type channel was activated at -20 mV, and the peak inward current occurred at +10 or +20 mV. The T-type channel current inactivated quickly in contrast to the much slower inactivation of the L-channel current. The voltage dependence of steady-state inactivation of the two channels was similar to that reported for other vascular smooth muscle preparations. An internal solution containing Cs2-aspartate maintained the calcium-channel currents for at least 20 min with only a 5-10% decline. BAY K 8644 had no effect on T-channel currents, but the L-channel current was increased by at least a factor of two. In addition, BAY K 8644 shifted the activation threshold, the peak inward current, and the steady-state inactivation-activation curves of L-type channel currents in the direction of hyperpolarization.

[Pathologic comparison between gastric carcinoma and lesions in peri-cancerous mucosa from two districts with different mortality rates in Gansu Province]

A pathologic comparative study on gastric carcinoma and lesions in peri-cancerous mucosa was done in 222 resected specimens of gastric carcinoma from two districts with different mortality rates in Gansu province. The adjusted mortality rates were 46.41 per 100,000 and 21.64 per 100,000 respectively. There were no significant difference in the histologic type and the gastric, intestinal and mixed types classified according to mucin histochemical stain and no significant difference in the detection rate of chronic atrophic gastritis (CAG), intestinal metaplasia (IM) and dysplasia in peri-cancerous mucosa either. These findings suggest that the type of gastric carcinoma be not related to the mortality rates either high or low and neither was there any apparent correlation between the CAG, IM and gastric carcinoma.

Study of in vitro antibacterial activity of 19 antimicrobial agents against Pseudomonas aeruginosa

The in vitro antibacterial activity of 19 antimicrobial agents against 40 strains of P aeruginosa was studied. The 19 antimicrobial agents included 7 semisynthetic penicillins, 6 third generation cephalosporins, 5 aminoglycosides and 1 quinolone agent. The minimal inhibition concentrations (MIGs) were measured by the serial dilution on solid agar. Ceftazidime was the most active in 19 antimicrobial agents again P aeruginosa (MIC50: 1 microgram/ml, MIC90: 2 micrograms/ml) Amikacin and ofloxaxin followed it in activity. Acylureido-penicillins, such as azlocillin, furbenicillin and piperacillin were highly active against P aeruginosa, which could inhibit, 92.5%, 90% and 85% of these strains at a concentration of 8 micrograms/ml. Cefsulodine and cefoperazone were also active against the same strains, inhibiting 92.5% and 99% of the strains at a concentration of 8 micrograms/ml. The potency of the agents mentioned above against P. aeruginosa was similar to that of aminoglycosides. The drug susceptibility of 10 strains isolated in our hospital was compared with that of 29 strains of other hospitals in Beijing. The MICS of 5 penicillins and 3 cephalosporins against the isolates of our hospital was higher than that of other hospitals, suggesting that the susceptibility of beta-lactam antibiotics against isolates of our hospital was lower. The effects of combined use of azlocillin with oxacillin and piperacillin with ofloxacin against 4 strains of carbenicillin-resistant P aeruginosa was studied using check-board testing. The synergy and partial synergy were observed in both combinations.

Tracheoesophageal puncture for voice restoration after extended laryngopharyngectomy

Tracheoesophageal puncture was performed in ten of our patients undergoing extended laryngopharyngectomy. Three fistulas were allowed to close, and two patients were dissatisfied with their results, which allowed for an overall 50% success rate in this subgroup. The resultant voice was objectively compared with similar groups of patients undergoing primary and secondary tracheoesophageal puncture after standard laryngectomy. There was no significant difference in maximum phonation time, average speaking intensity, and average fundamental frequency between these groups. However, the maximum intensity and average intensity were significantly lower for the flap group. Our results indicate that tracheoesophageal puncture should be attempted in patients undergoing the extended procedure, notwithstanding a lower expected success rate.

Virginiamycin metabolism in cattle rumen fluid

The antibiotic virginiamycin (VM) was extensively metabolized in cattle rumen fluid in vitro. The antimicrobial activity of VM decreased rapidly with an initial half-life of approximately 8 hr. In contrast, in buffer at near neutral pH, VM maintained its full activity for at least 24 hr. Four metabolites were isolated and identified using a combination of spectral techniques including FAB MS-MS, LC-MS, and 500 MHz NMR. The metabolites were all derived from reduction of the major component of virginiamycin, factor M. The minor component, factor S, was not metabolized in cattle rumen fluid. The metabolic pathways involved included C = C and C = O reduction as well as dehydroxylation. All metabolites were found to have less antimicrobial activity than the parent factor M. In addition to the metabolites, two factor M decomposition products were isolated after incubation of VM in buffer alone. These two products resulted from the dehydration of factor M and were shown to interconvert at room temperature.

Effect of probucol on development of diabetes mellitus in BB rats

Insulin-dependent diabetes mellitus (IDDM) results from an inflammatory process leading to destruction of the insulin-producing beta cells of the pancreas. Genetically mediated autoimmune processes are considered the most likely explanation for IDDM in humans, while viral infections, toxic agents, nutritional alterations and stress are also considered possibilities. The precise mechanisms by which autoimmunity, infections, toxins or other agents produce beta cell damage are not known. Toxin-induced diabetes in animals can be prevented by antioxidant therapy, while an agent that inhibits hydroxyl radical formation, desferrioxamine, extends the survival time of free allotypic islets in nonobese diabetic mice. The BB/W rat develops IDDM secondary to a pervasive autoimmune defect. This well-studied animal model develops IDDM with a highly predictable frequency and timing. This study describes the effects of the potent antioxidant, probucol, on the development of diabetes in BB rats by introducing it into standard rat chow at a 1% concentration at the time of weaning, and continuing this feeding schedule through 160 days of life. Control rats from split litters received standard chow only. Diabetes developed in 86.2% of the control rats at a mean age of 90.4 days. Probucol administration was associated with a reduction to 62% and a delay in diabetes diagnosis to 99.6 days. These very preliminary results suggest that probucol may be altering the inflammatory process, resulting in beta cell destruction in these genetically diabetes-prone rats.

The risks and benefits of clozapine versus chlorpromazine

Clozapine is an atypical antipsychotic drug with reduced risk of unwanted neurological effects in comparison with other drugs. In this multicenter study, 151 hospitalized schizophrenic patients were randomly assigned to treatment under double-blind conditions to assess the antipsychotic efficacy and safety of clozapine versus chlorpromazine. All patients exhibited tardive dyskinesia or other extrapyramidal side effects associated with at least two prior neuroleptics. Eleven patients were dropped from treatment due to extrapyramidal symptoms while being treated with chlorpromazine; only one clozapine patient's treatment was terminated for this reason. Clozapine patients exhibited clinical improvement superior to that of chlorpromazine patients as assessed by the Brief Psychiatric Rating and Clinical Global Impression scales. These results suggest that clozapine is well tolerated and may be therapeutically superior to chlorpromazine in treating psychotic behavior. Agranulocytosis potential can be minimized by frequent white blood cell counts and removing nonresponding patients from treatment prior to the peak risk period (months 2 through 6).

Diterpenoid Alkaloids of Aconitum sungpanase

A new diterpenoid alkaloid, sungpanconitine, was isolated from ACONITUM SUNGPANESE Hand.-Mazz. Its structure was determined on the basis of chemical and spectral evidence. Along with this new compound, four known diterpenoid alkaloids were isolated and identified.

Malignant fibrous histiocytoma of left atrium

A case is presented of malignant fibrous histiocytoma arising adjacent to a mitral Carpentier-Edwards bioprosthesis placed 6 years previously.

Phosphorylation heterogeneity of tryptic phosphopeptides of chicken riboflavin-binding protein

The tryptic phosphopeptide of hen egg white riboflavin-binding protein has been found to exist as a mixture of peptides which differ only with respect to the number of covalently bound phosphoryl groups. Anion-exchange chromatography was used to separate homologues of the tryptic phosphopeptide of egg white riboflavin-binding protein. Four peptide peaks were obtained and analyzed using plasma desorption mass spectrometry. Molecular ions obtained agree closely with calculated molecular weight values for phosphopeptides with 8, 7 and 5 phosphoryl groups. Amino acid analyses showed that the octa- and hepta-phosphorylated peptides were pure and had the same amino acid compositions.

Structural alterations that differentially affect the mutagenic and antitrichomonal activities of 5-nitroimidazoles

Two approaches have been used to develop nonmutagenic 5-nitroimidazoles. Both approaches are based on knowledge of the likely mechanisms by which this class of compounds cause mutagenicity. The first approach involved incorporating readily oxidizable gallate derivatives into the molecule. In one case, a very weakly mutagenic active antitrichomonal agent was obtained. The second approach involved incorporating a substituent at the C4 position of the ring. This generally resulted in a large reduction in mutagenicity and a lowering of antitrichomonal activity in vitro. In certain cases, however, mutagenicity was dramatically reduced while moderate antitrichomonal activity was retained. For example, 1,2-dimethyl-4-(2-hydroxyethyl)-5-nitroimidazole (5) showed good antitrichomonal activity in vitro (ED50 = 2 micrograms/kg) while possessing only 4% of the mutagenicity of metronidazole.

Alcohol and dilated cardiomyopathy: incidence and correlation with clinical outcome

Among a group of 28 elderly veterans with dilated cardiomyopathy regularly attending an outpatient heart failure clinic, half had a history of habitual heavy drinking. It was concluded that chronic heavy drinking was the only identifiable factor responsible for the heart failure in three of these patients. Eleven other patients also had chronic heavy drinking as a possible etiological factor of their heart failure in addition to Coronary Artery Disease and/or hypertension. Less than 50% of the heavy drinkers totally abstained from alcohol after seeking medical treatment although they reduced their drinking significantly. All three patients with clear alcoholic cardiomyopathy discontinued drinking and showed marked improvement in cardiac status. The discontinuation of drinking did not appear to be associated with improvement in the remaining heavy drinkers and those patients who reported a history of moderate drinking.

An unusual case of postoperative pseudoaneurysm of the left ventricle: Doppler echocardiographic findings

Two years and 9 months after aneurysmectomy of a true left ventricular aneurysm, a 55 year old man presented with clinical features suggestive of acute pericarditis. The echocardiogram revealed a large echo-free space outside the heart. Doppler study showed phasic flow between the echo-free space and the left ventricular cavity through a distinct interruption of the left ventricular apical wall endocardial echoes. The diagnosis of pseudoaneurysm was made and was subsequently confirmed by angiographic and operative findings. After successful repair, a repeat Doppler echocardiographic examination showed a marked reduction in the echo-free space, absence of communication with the left ventricle and no flow signal in the space.

Occupational exposure to chlorophenates. Renal, hepatic and other health effects

A group of 71 chlorophenate-exposed sawmill workers were identified as part of a group undergoing an extensive health and environmental evaluation in a pulp mill. This group was compared with a group (N = 351) with no physical proximity to the area in which chlorophenates were used. Exposure was higher for those directly handling the wood and lower for those working in the area but not handling the wood. Those with chlorophenate exposure were not significantly more likely to report a history of jaundice or liver, kidney or heart disease. Moreover, the serum creatinine, bilirubin, glutamic oxaloacetic transaminase (GOT), and alkaline phosphatase values did not differ from those of the reference group. The hemoglobin level was similar in the three groups. But the peripheral blood leukocyte count was marginally lower in the exposed groups and their hematocrit was reduced, significantly so for the heavily exposed group. Urinalysis showed an increased prevalence of microscopic hematuria, especially with lower cell counts. No unequivocal explanation is available for the reduced hematocrit or the low level of hematuria.

Multiple Ya subunits of glutathione S-transferase detected by monoclonal antibodies

Monoclonal antibodies to ligandin (YaYa) and glutathione (GSH) S-transferase B (YaYc) were produced by hybridomas derived from the fusion of mouse myeloma cells and spleen cells of mice immunized with the YaYa or YaYc proteins, respectively. Enzyme-linked immunosorbent assay was used to screen for antibody-producing clones. Immunoblotting of the subunits of transferase B, ligandin, and another GSH S-transferase containing Yb subunits showed that the monoclonal antibodies produced by two anti-YaYa subclones recognized the Ya subunits of both ligandin and transferase B, but they did not bind Yc or Yb subunits. It was also revealed that antibodies produced by several anti-YaYc subclones recognized the Yc subunit, but not the Ya subunit of the antigen which was used for the immunization of the mice. However, these monoclonal antibodies did bind the Ya subunit of ligandin. These results indicate that the Ya subunits of GSH S-transferase B and of ligandin do share at least one common determinant. However, these two Ya subunits are structurally distinct as evidenced by their differences in binding by monoclonal anti-YaYc antibodies.

Studies on the mechanism of activation and the mutagenicity of ronidazole, a 5-nitroimidazole

Substantial evidence implicates the obligatory nucleophilic attack by water at C4 for the elimination of the carbamate and subsequent immobilization by electrophilic attack on protein thiols. Consequently, the strong correlation between the structural requirements for protein alkylation and for mutagenicity in TA100 suggests a possible role of nucleophilic addition at C4 or at the 2-methylene carbon for the expression of mutagenicity. Further studies directed at evaluating this possibility are currently in progress.

Risks of lung cancer, chronic bronchitis, ischaemic heart disease, and stroke in relation to type of cigarette smoked

In a case control study of over 12 000 inpatients aged 35-74, risk of lung cancer, chronic bronchitis, and, particularly in those aged 35-54, ischaemic heart disease was positively associated with the number of manufactured cigarettes smoked daily and was negatively associated with long term giving up. Risk of stroke was not clearly related to smoking. Among manufactured cigarette smokers, lung cancer risk tended to be lowest in those who had always smoked filter cigarettes. This pattern was, however, evident only in men who additionally smoked pipes, cigars or handrolled cigarettes and in women, not being seen in men who smoked only manufactured cigarettes. Risk of lung cancer was not clearly related to time of switch to filter cigarettes. A markedly lower risk of chronic bronchitis was seen in men, but not women, who smoked filter rather than plain cigarettes. Heart disease risk did not vary by type of cigarette smoked 10 years before admission, but, compared with those who had never smoked filter cigarettes, those who had ever smoked filter cigarettes had a higher risk in men and a lower risk in younger women. Compared with the general population, markedly more controls were ex-smokers, suggesting incipient disease, whether or not smoking related, may alter smoking habits, thus affecting the interpretability of the findings. Control smokers were also relatively much more likely to report smoking plain cigarettes than expected. This comparison, not made in other studies relating risk to type of cigarette smoked, indicates that great care must be taken in verifying validity of reported smoking habits. While our findings are compatible with other evidence that risk of lung cancer and chronic bronchitis is probably reduced by switching from plain to filter cigarettes, they underline the difficulties in obtaining valid evidence from epidemiological studies.

Warfarin versus dipyridamole-aspirin and pentoxifylline-aspirin for the prevention of prosthetic heart valve thromboembolism: a prospective randomized clinical trial

In a prospective, randomized, parallel study, two regimens of platelet-suppressant therapy (PST)--dipyridamole-aspirin and pentoxifylline-aspirin--were compared with standard oral anticoagulation with warfarin in the prevention of prosthetic heart valve thromboembolism. In the entire group of 254 patients followed for 395.6 patient-years, the thromboembolic rate was significantly less in the warfarin group (warfarin vs dipyridamole-aspirin, p less than .005; warfarin vs pentoxifylline-aspirin, p less than .05). Subgroup analysis disclosed that, in patients with isolated mitral valve replacement, warfarin was superior to both of the PSTs with respect to the prevention of thromboembolism (warfarin vs dipyridamole-aspirin, p = .005; warfarin vs pentoxifylline-aspirin, p less than .05). Furthermore, a significant number of our patients could not tolerate the antiplatelet agents. However, in the rare situation in which repeated significant bleeding occurs despite careful adjustment of the dosage of warfarin, PST may be an acceptable alternate method of thromboembolism prophylaxis.

Erythrocyte aldehyde dehydrogenase and disulfiram-like side effects of hypoglycemics and antianginals

Disulfiram-like responses to various drug therapies are caused by elevated ethnol-derived blood acetaldehyde concentrations resulting from drug-induced inhibition of aldehyde dehydrogenase enzymes. We have found that the nitrate ester antianginal drugs, isosorbide dinitrate and nitroglycerin, are potent inhibitors of human erythrocyte aldehyde dehydrogenase. To further characterize this drug-induced enzyme inhibition, erythrocyte aldehyde dehydrogenase activities were measured in patients undergoing therapy with nitrate ester antianginals (isosorbide dinitrate and nitroglycerin) and sulfonylurea hypoglycemics (chlorpropamide and tolazamide). The erythrocyte enzyme was decreased by approximately 25% in sulfonylurea-treated patients, whereas in the nitrate ester-treated patients, an 88% inhibition was observed. The minimal enzyme inhibition in the sulfonylurea-treated group was unexpected because these therapies have well-documented disulfiram-like side effects. This weak inhibition contrasted with the severe inhibition observed in the nitrate ester-treated group where the disulfiram-like side effects are not considered a serious clinical problem. This apparent anomaly was attributed to differences in inhibition of the erythrocyte and liver aldehyde dehydrogenase by the parent drugs and their hepatic metabolites.

Bilateral congenital middle ear cholesteatomas

Congenital middle ear cholesteatomas remain of interest because of their relative rarity and unknown origin. A 4-month-old child presenting with bilateral congenital middle ear cholesteatomas forms the basis for this report. The nature of the epithelial debris found suggests an external origin. An extended transcanal tympanotomy approach for removal, based upon an operative experience of 11 similar ears, will be discussed.

Drug residue formation from ronidazole, a 5-nitroimidazole. VII. Comparison of protein-bound products formed in vitro and in vivo

In vivo experiments were conducted with ronidazole radiolabelled in the 2-14CH2-, 4,5-14C-, N-14CH3- and 4-3H-positions. The hepatic protein-bound residues, assessed by the radioactivity of exhaustively washed protein samples, were independent of the radiolabel position and occurred with 4-3H loss (greater than 80%) in excellent agreement to previous results obtained in vitro with anaerobic incubations of liver microsomes (Miwa et al., Chem. Biol. Interact., 41 (1982) 297). HPLC analysis of acid hydrolyzed in vivo protein-bound residues, obtained from [2-14CH2] ronidazole, produced a radiochromatographic profile which was virtually identical to that obtained from a similarly treated in vitro sample. Moreover, almost quantitative (76-96%) liberation of radiolabelled methylamine was obtained from hydrolysates of in vivo and in vitro residue samples formed from [N-14CH3] ronidazole. With 4,5-ring labeled ronidazole the distribution of total radioactivity of the protein hydrolysate on cation exchange resin and the fraction of the residue recovered as oxalic acid were nearly identical for the in vivo and in vitro products. We interpret these data to indicate that ronidazole alkylates proteins with retention of most of the carbon framework of the molecule, in vivo. It is also concluded that the in vitro model, previously used to examine the mechanism of protein alkylation, accurately reflects the salient process initially occurring in the intact animal during the formation of protein-bound residues of this drug.

Rat liver DT-diaphorase: regulation of functional mRNA levels by 3-methylcholanthrene, trans-stilbene oxide, and phenobarbital

Total liver poly(A+)-RNA isolated from untreated, and 3-methylcholanthrene-, trans-stilbene oxide-, and phenobarbital-treated rats has been translated in the rabbit reticulocyte lysate system in order to determine the effect of these xenobiotics on the level of translationally active DT-diaphorase mRNA. The in vitro translation systems were subjected to immunoprecipitation with rabbit IgG raised against purified DT-diaphorase and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The identity of the radiolabeled, immunoprecipitated product as DT-diaphorase was confirmed by limited peptide mapping using Staphylococcus aureus V-8 protease. These quantitation results demonstrate that 3-methylcholanthrene leads to an eight-fold elevation in functional DT-diaphorase mRNA at 8 h after a single administration of 3-methylcholanthrene; whereas, trans-stilbene oxide and phenobarbital produced only a modest elevation, two- to three-fold, in the functional DT-diaphorase mRNA level. These data indicate that the increase in the level of DT-diaphorase after 3-methylcholanthrene administration noted previously [B. Höjeberg, K. Blomberg, S. Stenberg, and C. Lind (1981) Arch. Biochem. Biophys. 207, 205-216] can be totally accounted for by an elevation in the mRNA level specific for this protein.

Pad-plate diffusion assay for virginiamycin in mash-type feeds

An assay procedure has been developed for virginiamycin in mash-type feeds which includes removing fat interferences from the feeds by a rapid petroleum ether wash, a citric acid extraction, an acetone extraction, and the use of the pad-plate diffusion system. The procedure eliminates the need for compensatory curves prepared from feeds of the same or similar composition. Recoveries from 10 laboratory-prepared feeds containing 11.0 micrograms virginiamycin/g averaged 89.3% with a coefficient of variation (CV) of 5.76%. Recoveries from a laboratory-prepared feed containing 13.2 micrograms virginiamycin/g averaged 89.9% (CV 9.92%). The procedure is simple, reasonably accurate, and precise.

A protein from human placental nuclei binds preferentially to 5-methylcytosine-rich DNA

The methylation of vertebrate DNA at the 5-position of approximately 3-10% of its cytosine residues occurs in a sequence-specific and tissue-specific manner and has been implicated in the control of transcription. How these differences are established and how they mediate the initiation or maintenance of transcription are unknown. DNA methylation might also have other roles, such as modulating DNA replication, transposition, DNA repair or chromosome configuration. These other roles suggested for DNA methylation would be consistent with the finding that tissue-specific differences in methylation of certain gene regions, highly repeated satellite DNA sequences and whole genomes often do not correlate with transcriptional activity. For DNA methylation to modulate the expression, maintenance or duplication of chromosomes, there should be effector macromolecules, presumably proteins, which specifically recognize 5-methylcytosine (m5C) residues in DNA. We describe here the first identification of a mammalian protein that binds preferentially to m5C-rich DNA sequences.