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PubMed2007

Production of bio-hydrogen by mesophilic anaerobic fermentation in an acid-phase sequencing batch reactor.

The pH and hydraulic retention time (HRT) of an anaerobic sequencing batch reactor (ASBR) were varied to optimize the conversion of carbohydrate-rich synthetic wastewater into bio-hydrogen. A full factorial design using evolutionary operation (EVOP) was used to determine the effect of the factors and to find the optimum condition of each factor required for high hydrogen production rate. Experimental results from 20 runs indicate that a maximum hydrogen production rate of 4,460-5,540 mL/L/day under the volumetric organic loading rate (VOLR) of 75 g-COD/L/day obtained at an observed design point of HRT = 8 h and pH = 5.7. The hydrogen production rate was strongly dependent on the HRT, and the effect was statistically significant (P < 0.05). However, no significant effect (P > 0.05) was found for the pH on the hydrogen production rate. When the ASBR conditions were set for a maximum hydrogen production rate, the hydrogen production yield and specific hydrogen production rate were 60-74 mL/g-COD and 330-360 mL/g-VSS/day, respectively. The hydrogen composition was 43-51%, and no methanogenesis was observed. Acetate, propionate, butyrate, valerate, caproate, and ethanol were major liquid intermediate metabolites during runs of this ASBR. The dominant fermentative types were butyrate-acetate or ethanol-acetate, representing the typical anaerobic pathway of Clostridium species. This hydrogen-producing ASBR had a higher hydrogen production rate, compared with that produced using continuous-flow stirred tank reactors (CSTRs). This study suggests that the hydrogen-producing ASBR is a promising bio-system for prolonged and stable hydrogen production.

Anaerobiosis↗
PubMed2002

Odor-stimulated glutamatergic neurotransmission in the zebrafish olfactory bulb.

The role of glutamate as a neurotransmitter in the zebrafish olfactory bulb (OB) was established by examining neuronal activation following 1). glutamate receptor agonist stimulation of isolated olfactory bulbs and 2). odorant stimulation of intact fish. Four groups of neurons (mitral cells, projection neurons; granule cells, juxtaglomerular cells, and tyrosine hydroxylase-containing cells; interneurons) were identified on the basis of cell size, cell location, ionotropic glutamate receptor (iGluR) agonist/odorant sensitivity, and glutamate, gamma-aminobutyric acid (GABA), and tyrosine hydroxylase immunoreactivity. Immunoreactive glutamate levels were highest in olfactory sensory neurons (OSNs) and mitral cells, the putative glutamatergic neurons. The sensitivity of bulbar neurons to iGluR agonists and odorants was established using a cationic channel permeant probe, agmatine (AGB). Agmatine that permeated agonist- or odor-activated iGluRs was fixed in place with glutaraldehyde and detected immunohistochemically. N-methyl-D-aspartic acid (NMDA) and alpha-amino-3-hydroxyl-5-methylisoxazole-4-propionic acid (AMPA)/kainic acid (KA) iGluR agonists and odorants (glutamine, taurocholic acid) stimulated activity-dependent labeling of bulbar neurons, which was blocked with a mixture of the iGluR antagonists, D-2-amino-5-phosphono-valeric acid (APV) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). The AMPA/KA antagonist CNQX completely blocked glutamine-stimulated AGB labeling of granule cells and tyrosine hydroxylase-containing cells, suggesting that, in these cell types, AMPA/KA receptor activation is essential for NMDA receptor activation. However, blocking AMPA/KA receptor activity failed to eliminate AGB labeling of mitral cells or juxtaglomerular cells. Collectively, these findings indicate that glutamate is the primary excitatory neurotransmitter in the zebrafish OB and that iGluR subtypes function heterogeneously in the bulbar neurons.

Animals↗
PubMed2006

Simultaneous determination of natural and synthetic estrogens by EKC using a novel microemulsion.

A novel microemulsion based on sodium bis(2-ethylhexyl) sulfosuccinate (AOT) was developed for the simultaneous determination of natural and synthetic estrogens by microemulsion EKC (MEEKC). The microemulsion system consisted of 1.4% w/w AOT, 1.0% w/w octane, 7.0% w/w 1-butanol and 90.6% w/w 20 mM sodium salt of 3-(cyclohexylamino)-2-hydroxy-1-propanesulfonic acid (CAPSO) and 10 mM phosphate buffer at pH 12.5. A baseline resolution in the separation of estrone, 17beta-estradiol, estriol, estradiol 17-hemisuccinate, etinilestradiol, estradiol 3-benzoate, and estradiol 17-valerate was achieved in comparison to the traditional MEEKC system with SDS in less than 15 min. The optimized electrophoretic conditions included the use of an uncoated-silica capillary of 60 cm of total length and 75 microm id, an applied voltage of 25 kV, a temperature of 25 degrees C and 214 UV-detection. Parameters of validation such as specificity, linearity, accuracy, LOD, LOQ and robustness were evaluated according to international guidelines. Due to its simplicity, accuracy, and reliability, the proposed method can be an advantageous alternative to the traditional methodologies for the analysis of natural and synthetic estrogens in different pharmaceutical forms.

Buffers↗
PubMed1983

Correlation of drug sensitivity on human colon adenocarcinoma cells grown in soft agar and in athymic mice.

A well-differentiated colorectal tumor T 219 which grows as a xenograft in athymic mice (human-tumor-nude-mouse system) and forms colonies in culture (soft agar colony-formation assay) has been used to test the correlation between the above two methods of exposure of human tumor cells to antineoplastic agents. In in vitro studies, two protocols were used: 1 h drug exposure and continuous drug exposure. In the 1 h drug exposure experiments six drugs, doxorubicin (DX), 4'-deoxydoxorubicin (deoDX), 4'epidoxorubicin(epiDX), 4'-O-methyldoxorubicin (O-DX), N-trifluoroacetyldoxorubicin-14-valerate (AD-32) and 5-fluorouracil (FUra) were studied, while in continuous drug exposure experiments four of the above drugs (DX, deoDX, epiDX, O-DX) were studied. The survival of the tumor clonogenic cells (HC219) was determined by counting the number of colonies formed during 13-14 days of incubation and dose-response curves were obtained. In in vivo studies, the mice were treated with all of the drugs used in in vitro 1 h drug exposure experiments (DX, deoDX, epiDX, O-DX, AD-32 and FUra). To quantitate the chemotherapeutic effectiveness of the drugs, T/C% (relative tumor volume of treated group as percentage of the control group) values were calculated each time the tumors were measured. The experimental data suggest that in vitro 1 h drug exposure results are in good agreement with the in vivo results, while the continuous drug exposure results do not agree with the in vivo data. The most active drug in in vivo studies, deoDX, was found to be the most active drug in the in vitro 1 h drug exposure experiments as well. However, in continuous drug exposure experiments, O-DX, not deoDX, was found to be the most active drug. Activities of the other drugs tested also differed from their respective activities in in vivo studies. Although the relative effectiveness of various drugs can be compared by determining molar concentrations of the drugs producing 50% inhibition of colonies (ID50) the expression, PEI = LD10/ID50 X 1000, which takes into consideration toxicity of the drugs, is probably a better indicator of the in vitro drug activity. The results suggest that soft agar colony-formation assay (with established cell lines from the same tumor) may be used for the prediction of in vivo activity of potential antineoplastic agents against human tumor xenografts in nude mice.

Adenocarcinoma↗
PubMed1991

Derivatives of butyric acid as potential anti-neoplastic agents.

A novel derivative of butyric acid, pivalyloxymethyl butyrate (AN-9) has been shown, in vitro, to: (a) induce cytodifferentiation and inhibit the proliferation of leukemic cells; (b) inhibit the growth and formation of Lewis lung carcinoma colonies in semi-solid agar. AN-9 affect cells at about 10-fold lower concentration and at a faster rate than does butyric acid. The pivalyloxymethyl esters of propionic, isobutyric and valeric acids do not elicit effects similar to those of AN-9, while the isobutyryloxymethyl butyrate does, which strongly suggests that the activity of AN-9 stems from intracellular metabolic degradation of the pro-drug to butyric acid. In vivo, AN-9, increased the survival of mice in Lewis lung carcinoma primary cancer model and significantly decreased the number of lung lesions of the animals inoculated with highly metastatic cells, but did not affect their life span. Acute LD50 studies have shown that AN-9 possesses low toxicity. These results suggest that AN-9 is a potential anti-neoplastic agent as well as a tool for investigation of the differentiation induction mechanism.

Animals↗
PubMedDate not supplied

The effect of castration and estrogen therarapy on serum high-density lipoprotein cholesterol.

The effect of castration on serum high-density lipoprotein (HDL) cholesterol was studied in 11 women with fairly regular menstruation. The HDL cholesterol levels before and one month after castration did not differ significantly. The effect of intramuscular estrogen therapy on HDL cholesterol was investigated in six castrated women. Ten days after injections of both 10.0 mg of estradiol valerate and 2.5 mg of estradiol benzoate plus 10.0 mg of estradiol phenylpropionate, HDL cholesterol was increased significantly. Fifteen days later, HDL cholesterol levels returned to the pretreatment values.

Castration↗
PubMed1992

Vitamin D analogues in the treatment of psoriasis.

Psoriasis is a chronic hyperproliferative skin disease in which inflammatory and immunologic processes may play important pathophysiologic roles. Recently the skin has been identified as a target tissue for vitamin D. Because 1,25-dihydroxy vitamin D3 inhibits epidermal proliferation and promotes epidermal differentiation, it has been introduced for the treatment of psoriasis vulgaris. In addition to 1,25-(OH)2-D3, synthetic vitamin D3 analogues have undergone clinical evaluation. Calcipotriol (INN) (calcipotriene [USAN]) has been studied most extensively. Compared with 1,25-(OH)2-D3, calcipotriol is about 200 times less potent in its effects on calcium metabolism, although similar in receptor affinity. Topical calcipotriol 50 micrograms/g applied twice daily is efficacious and safe for the treatment of psoriasis. Because topical calcipotriol is slightly more efficacious than betamethasone 17-valerate and dithranol, calcipotriol should be considered a first line drug in the management of psoriasis. These results illustrate that it is possible to separate the vitamin D effects on the cellular level from those on calcium metabolism not only in vitro, but also in a clinical setting.

Humans↗
PubMed1976

Induction by short-chain fatty acids of alkaline phosphatase activity in cultured mammalian cells.

Short-chain fatty acids, such as propionic, n-butyric, n-butyric, n-valeric, isovaleric, n-caproic, and n-caprylic acids, induce alkaline phosphatase activity in cultured mammalian cells. Long-chain fatty acids have no similar effects. With B-6 cells (mouse X Chinese hamster cell hybrids), n-butyrate at 2 to 5 mM exhibits the greatest activity. Induction begins exponentially about 24 hours after addition of the fatty acid and continues over 48 hours. Studies on the inducing activity-structure relationship revealed the necessity of a carboxyl and an ethyl or longer alkyl group. n-Butyrate shows a marked synergistic action of induction when added along with other types of inducers: adenosine 3':5'-cyclic monophosphate (cAMP) or 5-bromodeoxyuridine (BrdU). Treatment of other cell lines with either n-buryrate, cAMP, or BrdU revealed a cell-type specific response pattern of alkaline phosphatase. The biological significance of this effect of short-chain fatty acids is discussed.

Acid Phosphatase↗
PubMed1993

Distribution of lectin binding sites in the oviducts of cycling and hormone-treated pigs.

Gamete transport, fertilization, and early embryonic development take place in different regions of the oviduct and under different hormonal conditions. The objective of this study was to use lectins to detect variation in the distribution of glycosylated molecules on the surface of the epithelia that influence these events. Oviducts were collected from gilts on day 1 (estrus) and day 16 (diestrus) of the estrous cycle, and from gilts that were bilaterally ovariectomized on day 4 of the estrous cycle, and were subsequently treated with estradiol valerate (100 micrograms/day), progesterone (200 mg/day), or corn oil vehicle for 11 days. Six biotinylated lectins, Triticum vulgaris (WGA), Arachis hypogaea (PNA), Ulex europeus (UEA-I), Dolichos biflorus (DBA), Ricinus communis (RCA-I), and Canavalia ensiformis (Con A), were used to probe tissue from the isthmus and ampulla using peroxidase-conjugated avidin as the marker. In cyclic gilts, WGA and DBA stained more strongly in the isthmus than the ampulla on both cycle days. Staining with PNA was patchy, but greater on the apical surface of isthmic epithelium on day 16 than day 1. With UEA-I, staining was more intense in the ampulla on day 16 than day 1. Staining by PNA and UEA-I was suppressed in both the ampulla and isthmus with estradiol treatment. DBA staining was suppressed in the isthmus with both estradiol and progesterone treatments. Cilia were labelled by all lectins except WGA and PNA. Thus glycosylation patterns vary in the porcine oviduct with region and hormonal state, reflecting the variety of events that may be influenced.

Animals↗
PubMed2003

Inhibition of alpha-ketoglutarate dehydrogenase complex promotes cytochrome c release from mitochondria, caspase-3 activation, and necrotic cell death.

Mitochondrial dysfunction has been implicated in cell death in many neurodegenerative diseases. Diminished activity of the alpha-ketoglutarate dehydrogenase complex (KGDHC), a key and arguably rate-limiting enzyme of the Krebs cycle, occurs in these disorders and may underlie decreased brain metabolism. The present studies used alpha-keto-beta-methyl-n-valeric acid (KMV), a structural analogue of alpha-ketoglutarate, to inhibit KGDHC activity to test effects of reduced KGDHC on mitochondrial function and cell death cascades in PC12 cells. KMV decreased in situ KGDHC activity by 52 +/- 7% (1 hr) or 65 +/- 4% (2 hr). Under the same conditions, KMV did not alter the mitochondrial membrane potential (MMP), as assessed with a method that detects changes as small as 5%. KMV also did not alter production of reactive oxygen species (ROS). However, KMV increased lactate dehydrogenase (LDH) release from cells by 100 +/- 4.7%, promoted translocation of mitochondrial cytochrome c to the cytosol, and activated caspase-3. Inhibition of the mitochondrial permeability transition pore (MPTP) by cyclosporin A (CsA) partially blocked this KMV-induced change in cytochrome c (-40%) and LDH (-15%) release, and prevented necrotic cell death. Thus, impairment of this key mitochondrial enzyme in PC12 cells may lead to cytochrome c release and caspase-3 activation by partial opening of the MPTP before the loss of mitochondrial membrane potentials.

Animals↗
PubMed1982

Gonadal influences on the inhibition of monoamine oxidase type B activity.

Monoamine oxidase type B (MAO-B) was similarly active in the hypothalamus of 60-day-old male and female Charles River rats. A single, 2 mg/kg IP injection of deprenyl, however, resulted in a significantly greater inhibition of hypothalamic MAO-B in normal males than in normal females. Repeated administration of estrogen (estradiol valerate) to intact males postnatally, a treatment which disrupts the masculinization process, although not provoking true "feminization," decreased the inhibition of MAO-B, thus abolishing the sex-specific difference. The intensity of deprenyl-provoked hypothermia and ptosis in males exceeded that of females; neonatal and postnatal estrogenization of males resulted in diminution of these effects. Androgen administration to neonate females did little affect the biochemical and in vivo parameters of MAO inhibition. It is concluded that sex-specific, biochemical differences in MAO-B inhibition may have pharmacological correlates, and both facets of MAO inhibition are sensitive to neonatal exposure to estrogen.

Animals↗
PubMed2003

Micronization of anti-inflammatory drugs for pulmonary delivery by a controlled crystallization process.

Jet-milling as the common way for micronization of drugs shows several disadvantages. Drug powder properties are decisive for pulmonary use because, besides a small particle size, a good deagglomeration behavior is required. In this study, several anti-inflammatory drugs [beclomethasone-17,21-dipropionate (BDP), betamethasone-17-valerate (BV), triamcinolone acetonide, ECU-R2, budesonide, and prednisolone] were micronized by controlled crystallization without any milling processes. First the drug is dissolved in an organic solvent (BDP/BV: 4%; ECU-R2: 1% in acetone) and precipitated by a solvent change method in the presence of a cellulose ether (hydroxypropylmethylcellulose) as stabilizing hydrocolloid. By rapid pouring the solution of hydroxypropylmethylcellulose in water (BDP/BV: 0.005%; ECU-R2: 0.025%) into the drug solution under stirring in a relationship (v/v) of 1:16 (BDP/BV), 1:4 (ECU-R2), the previously molecularly dispersed drug was associated to small particles and stabilized against crystal growth simultaneously. This dispersion was spray-dried, resulting in a drug powder with a uniform particle-size distribution and a drug load of up to 98% (BDP, BV). The mean particle size of the drug was lower than 5 microm in most cases and consequently in the respirable range. Whereas the fine particle fraction (<5 microm, measured without excipients and without an inhalation device) of jet-milled drugs is 9.5 (BDP) or 13.1 (ECU-R2), fine particle fractions of 25.6% (BDP) resp. 78.2% (ECU-R2) are obtained with the spray-dried powders. As the formation of the small crystals requires a rapid solvent change process, the affinity of the hydrocolloid, and a high difference between the solubility in the solvent and nonsolvent, the drug's partition coefficient limits the method as drugs which are more hydrophilic form larger particles.

Administration, Inhalation↗
PubMed1975

Determination of estrogens in dosage forms by fluorescence using dansyl chloride.

A sensitive, reproducible, fluorometric procedure for the determination of estrogens in pharmaceutical preparations is presented. The estrogens are determined fluorometrically following their reaction with dansyl chloride. The optimum conditions for the reaction such as pH, reaction solvent composition variations, and speed of reaction are discussed. In addition, a linearity study of the relationship between concentration and fluorescence intensity for estrone, estradiol, and ethinyl estradiol is reported. Solvent extraction procedures based on acid-base behavior or column chromatography are used when necessary to isolate the estrogen prior to reaction with dansyl chloride and fluorometric measurement. The recovery of estrogens from spiked samples indicated that the proposed method is efficient and reproducible. Comparison of the dansyl procedure with the official NF method in the analysis of estrone aqueous suspension showed the proposed method to be accurate and more precise than the NF assay. Estrone aqueous suspension, estradiol in sesame oil, estradiol valerate in castor oil and in sesame oil (in the latter case, in the presence of testosterone), estradiol benzoate in sesame oil, and ethinyl estradiol tablets (0.5 mg/tablet) from commercial sources were satisfactorily analyzed, with average results within compendial limits and no coefficient of variation greater than 2%.

Castor Oil↗
PubMed1977

Bioavailability and activity of topical corticosteroids from a novel drug delivery system, the aerosol quick-break foam.

Experiments were conducted to: (a) compare the bioavailability of betamethasone benzoate in a quick-break aerosol foam and semisolid dosage forms, (b) compare the activity of betamethasone benzoate, betamethasone valerate, clobetasol propionate, triamcinolone acetonide, desonide, flumethasoid reservoir formation in skin, and (d) assess the effect of a natural moisturizer. Efficacy was determined by a graded response 6-hr occluded vasoconstriction test with subsequent reocclusion for reservoir demonstration. Moisturizer effect was assessed by a nonoccluded vasoconstriction test using "plain" and sodium 2-pyrrolidone-5-carboxylate-containing concentrates on arms pretreated with water or moisturizer. The activities of betamethasone benzoate concentrate, collapsed foam, ointment, and gel were similar and significantly better than the activity of the cream. Clobetasol propionate was significantly better than the other medicated concentrates, which were equivalent. Steroid-induced blanching decreased in the presence of a moisturizer.

Administration, Topical↗
PubMed1977

Prostaglandin monolayers II: monomolecular film behavior of dinoprost C-15 alkyl esters.

Monomolecular film compression-relaxation behavior was examined for select dinoprost C-15 alkyl esters. Higher homologs of the series such as palmitate and decanoate esters yielded stable expanded monolayers that exhibited minimal relaxation of surface pressure during noncompression. Their limiting molecular areas were consistent with a Hirschfelder model projection in which the prostaglandin moiety assumes a horizontal orientation at the interface with its alkyl ester chain oriented vertical to the surface plane. Shorter chain homologs such as hexanoate, valerate, butyrate, propionate, and acetate also formed expanded monolayers but exhibited increased instability with decreased alkyl chain length, as reflected in their lower surface pressure development during compression and significant relaxation of pressure during noncompression. Such instability can be tied to their increased solubility in the subphase solution and higher desorption rate from the interface.

Chemical Phenomena↗
PubMed1978

Radioimmunoassay of oxfendazole in bovine, equine, or canine plasma or serum.

A simple radioimmunoassay was developed for the determination of oxfendazole in plasma. Oxfendazole N-1(3)-valerate was coupled to polylysine via a carbodiimide reaction, and antiserum was developed in rabbits after inoculation with oxfendazole--polylysine conjugate. The assay was developed so that oxfendazole could be measured directly in a 0.1-ml aliquot of diluted or undiluted plasma. With the developed procedure, 200 pg of oxfendazole/ml of plasma can be determined quantitatively. Cross-reactivity was determined for closely related compounds and metabolites. The method was used to determine plasma concentration--time profiles in dogs and calves.

Animals↗
PubMed1981

High-performance liquid chromatographic assay for fenoprofen in human plasma.

A high-performance liquid chromatographic method is described for the quantitation of fenoprofen, dl-2-(3-phenoxyphenyl)-propionic acid, in human plasma. The proteins in plasma were precipitated by the addition of hydrochloric acid. Fenoprofen and the internal standard, dl-2-(4-phenoxyphenyl)valeric acid, were extracted into butyl chloride and then back-extracted into sodium hydroxide. The aqueous solution was injected onto a reversed-phase alkylphenyl column, and the compounds were eluted using a mobile phase of acetonitrile-water-acetic acid (50:50:2 v/v/v). At a flow rate of 1 ml/min, the retention times of fenoprofen and the internal standard were 8 and 12 min, respectively. The absorbance was monitored at 272 nm. The method requires 1.0 ml of plasma and is sensitive to 0.5 microgram/ml. This procedure has been used for routine assay of multiple samples from bioavailability and compliance studies.

Biological Availability↗
PubMed1982

Concomitant adsorption and stability of some anthracycline antibiotics.

Using liquid scintillation counting and liquid chromatographic techniques, it has been demonstrated that the anthracycline antibiotics, doxorubicin hydrochloride, N-trifluoroacetyladriamycin-14-valerate, and N-trifluoroacetyladriamycin-14-octanoate, can be strongly absorbed to the walls of containers, depending on the nature of both the container material and the solute. It also has been shown that the esters are unstable in the chemical growth media commonly used in cell culture studies. Both the adsorption and stability effects are suggested as being factors which should be carefully considered in interpretation of the in vitro and perhaps in vivo activities of the anthracycline esters.

Adsorption↗