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At least 1,207 records · Page 67Linked to original sources
PubMed2000

Monitoring of the levodopa concentration-response relationship in Parkinson's disease.

Motor fluctuations and abnormal involuntary movements are common complications encountered in advanced Parkinson's disease (PD) patients with long-term levodopa therapy. Monitoring of plasma levodopa concentrations and clinical effects has been reported to benefit the management of these complications. However, to our knowledge, there is no data available in Taiwan concerning the correlation between the plasma levodopa levels and motor fluctuations. In this study, we developed the laboratory methodology for plasma levodopa determination by using the aluminum extraction procedure and HPLC-ED. Serial blood samples and motor scores were obtained from 7 PD patients, and the correlation between plasma levodopa levels and motor responses were studied individually. In three patients with wearing-off phenomenon, plasma levodopa concentrations are compatible with the clinical "on" and "off" states. In the other four patients with complex fluctuating responses, their levodopa dosages were adjusted by the results of monitoring. Better motor responses were achieved by optimization of the levodopa pharmacokinetics in these patients. Our preliminary data suggest that simultaneous monitoring of plasma levodopa concentrations and clinical effects might be helpful to improve the therapeutic strategy in some of the parkinsonian patients with fluctuating responses to levodopa.

Adult↗
PubMed1991

Ethanol production by thermotolerant yeast and its UV resistant mutants.

Six thermotolerant yeasts were isolated at 37 degrees C from over-ripe grapes by serial dilution technique using glucose yeast extract medium. Purified yeast cultures were screened for ethanol production at 37 degrees C by batch fermentation, using cane molasses containing 20% sugars. Sugar conversion efficiency of these isolates varied from 66.0 to 88.5% and ethanol productivity from 1.11 to 1.73 ml/l/h. The highest ethanol producing isolate was exposed to UV radiations and 13 mutants were picked up from the UV treatment exhibiting 0.1 to 1.0%, survival. The UV mutants varied in cell size from parent as well as among themselves. Determination of ethanol produced by all the mutants revealed that only five mutants resulted in 4.5 to 6.2% increase in sugar conversion and 8.25 to 18.56% increase in ethanol concentration coupled with maximum ethanol productivity of 2.4 ml/l/h in 48 h of batch fermentation of cane molasses (20% sugars) at 37 degrees C temperature.

Ethanol↗
PubMedDate not supplied

Maternal hypothyroxinemia: psychoneurological deficits of progeny.

Maternal thyroid function was evaluated clinically, by reproductive history, and by serial measurements of serum butanol-extractable iodine (thyroxine-like iodine), two before and two after 24 gestational weeks during 1,349 pregnancies. Three percent of the women were hypothyroxinemic. Developmental, intellectual, and motor abilities of progeny born to (Group I) 210 euthyroxinemic, (Group II) 15 hypothyroxinemic given adequate thyroid replacement therapy, and (Group III) 21 inadequately treated hypothyroxinemic women were compared. The groups of mothers exhibited no significant differences in intelligence, years of education, or chronological age. Mean developmental and intellectual scores at eight months, four and seven years of Group II progeny evidenced remarkably consistent similarity to scores of siblings and controls. At each age, mean developmental and intellectual scores were lower for Group III progeny, and motor scores of the latter were lowest. Some progeny of Group II mothers, treated only after 12 or 29 weeks, failed the ball catch and line walk tests; some had strabismus and other ocular disturbances. Could these deficits have originated with maternal hypothyroxinemia during first semester weeks before the thyroid-pituitary axis matures? Now in 1990-1991, early findings fit into the modern concepts of significant maternal gestational transfer of thyroxine to the fetus. The authors encourage prenatal and/or early gestational screening for maternal hypothyroxinemia and urge prescription of adequate thyroid replacement therapy for hypothyroxinemic women.

Adolescent↗
PubMed1978

Characterization by molecular hybridization of two viral populations derived from a radiation leukemia virus.

Two leukemogenic viral populations were derived from a radiation leukemia virus of the C57BL mouse. One (FB), in which only B-tropic virus could be detected, was obtained in vivo by serial passage of cell-free extract in newborn rats. The second (3C), a complex containing at least B-tropic and xenotropic viruses, was produced in vitro by a permanent cell line (13-3C) established from the spleen of a virus-infected C57BL mouse. In molecular hybridization experiments, the 70S RNA of Gross leukemia virus hybridized 96 and 78% of FB and 3C radioactive complementary DNA's, respectively, with a relatively high thermal stability of the duplexes formed. In contrast, the 70S RNA of Rauscher leukemia virus hybridized 23 and 20% of the FB and 3C DNA probes, respectively, with a low thermal stability. The rat-grown FB virions exhibited 50% genome homology with the viruses produced in vitro on the 13-3C cells. Finally, hybridizing the FB and 3C probes with normal or leukemic mouse spleen DNA's resulted in 89 to 100% homology. The rat-grown virions did not appear to contain detectable rat cellular DNA sequences, while about 20 complete copies of their nucleotide sequences were detected in covalent linkage with FB-infected rat spleen DNA. These findings strongly support the endogenous murine origin of the investigated virions.

AKR murine leukemia virus↗
PubMed1998

Evaluating adrenal activity in African wild dogs (Lycaon pictus) by fecal corticosteroid analysis.

A noninvasive corticosteroid hormone monitoring technique was validated for use in African wild dogs (Lycaon pictus). The double-antibody 125I radioimmunoassay for corticosterone was validated by demonstrating parallelism between serial dilutions of wild dog fecal extracts and the standard curve, recovery of corticosterone added to fecal extracts, and the time course of fecal corticoid excretion after an exogenous adrenocorticotropic hormone (ACTH) challenge. All feces were collected from three female and two male African wild dogs for 72 hr before and 144 hr after i.m. injection of long-acting ACTH (Acthar Gel, 400 IU). Fecal corticosterone immunoreactivity increased 10-30-fold within 24 hr of ACTH administration in all individuals, with peak concentrations from 1,200-8,000 ng/g. High-pressure liquid chromatography analysis revealed that >90% of all corticosterone immunoreactivity was associated with a single peak that exhibited intermediate polarity relative to cortisol and corticosterone reference tracers. Fecal corticosterone immunoreactivity appears to reflect adrenal activity in the African wild dog and, therefore, may be useful for evaluating stress. From a conservation perspective, these techniques can complement in situ and ex situ research studies designed to evaluate how environmental conditions and management strategies affect overall animal health.

Adrenal Cortex Hormones↗
PubMed1992

[Sensitive identification of human blood and simultaneous determination of ABO blood group from a minute bloodstain by an ELISA-ABC method].

Sensitive identification of human blood and the determination of ABO blood group from a minute bloodstain were simultaneously carried out by a direct ELISA-ABC method. A cotton thread (1 cm in length) stained with 1 microliter of human or animal blood was stored for 2-4 weeks at room temperature. Hemoglobin (Hb) of the bloodstained thread was gently extracted with 100 microliters of PBS at room temperature, and the thread was washed with PBS to dehemoglobinize. And ABH blood group antigens were extracted from the same dehemoglobinized thread with 100 microliters of 5% ammonia solution at 56 degrees C. The extracts of PBS and ammonia were two-fold serially diluted with 0.1 M sodium carbonate buffer, coated to the wells of a flat bottomed microplate. The PBS extract was tested with a biotinylated antibody against human HbA0 for identification of human blood. Human blood was clearly distinguishable from bloods of other species including Japanese monkey. The minimum detection limit of human blood of the PBS extract of the bloodstained thread was 1:40,960 (3.4 ng Hb), and the limit was found to be approximately 200 times higher than that obtained by a leucomalachite green test or by a precipitation ring test using anti-human HbA serum. The ammonia extract was tested with biotinylated anti-A, anti-B and anti-H antibodies for ABO blood grouping. ABH antigens of the ammonia extract of the bloodstained thread were clearly detected. The minimum determination limits of blood group A, B, AB and O of the ammonia extracts were 1:160, 1:160, 1:80 and 1:160, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

ABO Blood-Group System↗
PubMed1987

Presence of thyroxine in eggs and changes in its content during early development of chum salmon, Oncorhynchus keta.

In order to examine the role of thyroid hormones during salmonid development, techniques were developed for quantitative extraction of thyroxine from eggs, whole embryos, and alevins of chum salmon (Oncorhynchus keta) at various stages of development. Frozen eggs, embryos, alevins, or fry were homogenized in ice-cold methanol. The homogenate was centrifuged, and the supernatant was washed with a mixture of chloroform and 0.05% CaCl2. The aqueous layer was lyophilized, and the residue was redissolved in barbital buffer for thyroxine radioimmunoassay (RIA). Serial dilutions of the egg or tissue extracts gave inhibition slopes that were parallel to that of the thyroxine standard in the RIA. Immunoreactivity of the extracts coeluted with thyroxine standard in reverse-phase HPLC on an ODS column. Recovery of thyroxine from egg and tissue extracts was estimated from the recovery of 125I-labeled thyroxine added to the initial homogenates. Thyroxine content of eggs just after fertilization was 4-5 ng/egg, and this level was maintained until hatching. A decrease in thyroxine content was seen during yolk absorption. Total thyroxine increased to about 10 ng/fish, a level higher than that in the unfertilized egg, at the time of complete yolk absorption, and decreased within 10 days to a low level of 1 ng/fish. These findings are discussed in relation to the role of maternal thyroid hormones during early development and also to the onset of larval thyroid function.

Animals↗
PubMed1981

Enhanced neutral protease activity in proliferating rheumatoid synovial cells.

Proteolytic enzymes associated with rheumatoid synovial cells (RSC) have been implicated in the degradation of articular cartilage. Proteases have been measured in proliferating rheumatoid synovial cells (P-RSC), proliferating nonrheumatoid synovial cells (P-NSC), and their nonproliferating counterparts (NP-RSC and NP-NSC). The P-RSC and P-NSC exhibit enhanced total surface-associated plus secreted neutral protease activity, as compared with NP-RSC and NP-NSC. The P-RSC exhibited significantly higher protease activity in this category compared to P-NSC. The RSC also secreted higher levels of secreted proteases alone compared to NSC. The secreted protease activity alone was not related to the proliferative state of the cells. Extractable protease activity was measured in early-passaged and serially-passaged P-RSC, NP-RSC, P-NSC, and NP-NSC. Extractable cellular protease activity measured at pH ranges from 5.0 through 8.0 was not significantly different between P-RSC and NP-RSC or between P-NSC and NP-NSC. The RSC contained elevated extractable cellular protease activity measured at pH ranges from 5.0 through 8.0 compared to extracts from later-passaged cells. The neutral protease activity in the early-passaged RSC was also higher than that measured at pH 6.0 or 8.0. In synovial cells cellular protease activity was related to the proliferative state and the origin of the cells. The P-RSC exhibited the highest levels of surface associated plus secreted neutral protease activity. The RSC also possessed the highest levels of extractable protease activity compared to NSC.

Arthritis, Rheumatoid↗
PubMed2003

Solid-phase microextraction and gas chromatography olfactometry analysis of successively diluted samples. A new approach of the aroma extract dilution analysis applied to the characterization of wine aroma.

The relationship between the composition and the aroma of the wine can be established by using gas chromatography with olfactometric detection (sniffing or GCO), which combines the chromatographic response with the human nose response. To evaluate the contribution of the odor compounds in wine aroma, we designed a new approach of the aroma extract dilution analysis (AEDA) that lies in the GCO analysis of serially diluted wine samples using headspace solid-phase microextraction (HS-SPME) as the extraction technique. The fiber coating used was Flex divinyl-carboxen-polydimethylsiloxane. The method developed was applied to determine the aromatic composition of a red Grenache wine from Priorat (Spain). The method allows 38 important odorants to be determined in the AEDA study, 30 of them precisely identified. These results are similar to those reported by other studies related to this variety of wine. HS-SPME is a suitable technique to obtain representative extracts of wine aroma with several advantages such as simplicity, speediness, and little sample manipulation.

Chromatography, Gas↗
PubMed1999

No evidence for an ischemic penumbra in massive experimental intracerebral hemorrhage.

OBJECTIVES: To determine the effect of massive intracerebral hemorrhage (ICH) on regional cerebral blood flow (rCBF) and metabolism, and to test the hypothesis that there is persistent ischemia in the perihematoma region after ICH. BACKGROUND: Cerebral ischemia is postulated to be one of the mechanisms of neural injury after ICH. Presumably the hematoma induces ischemia by mechanical compression of the surrounding microvasculature. METHODS: The authors induced ICH in eight anesthetized mongrel dogs by autologous blood injection (7.5 mL) under arterial pressure in the deep white matter adjacent to the left basal ganglia. They measured serial rCBF using radiolabeled microspheres in regions around and distant to the hematoma, as well as cerebral oxygen extraction, oxygen consumption (CMRO2), glucose utilization, and lactate production by serial sampling of cerebral venous blood from the sagittal sinus. Mean arterial pressure (MAP) and intracranial pressure (ICP) were monitored continuously. All measurements were recorded at 0.5, 1.0, 2.0, 3.5, and 5.0 hours after induction of ICH and compared with prehematoma values. Evans Blue dye was injected at the end of the experiment, and intensity of staining was compared with three control animals. RESULTS: Compared with prehematoma ICP (12.5+/-2.0 mm Hg, mean+/-standard error), significant elevation in ICP was observed after ICH peaking at 5 hours (34.4+/-5.2 mm Hg). Compared with prehematoma MAP (125.8+/-7.0 mm Hg), significant elevation in MAP was observed at 120 minutes after onset of hematoma (139.1+/-4.6 mm Hg), with return to the prehematoma value by 5 hours. There were no significant changes observed in cerebral oxygen extraction (51.4+/-4.3% versus 44.8+/-4.9%) and CMRO2 (1.8+/-0.3 versus 1.64+/-0.2 mL O2/100 g/min) at 5 hours posthematoma (or any other posthematoma measurement) compared with prehematoma values. There were no significant differences observed in rCBF in the perihematoma gray (18.2+/-0.9 mL/100 g/min versus 20.1+/-1.5 mL/100 g/min) or white matter (15.6+/-1.4 mL/100 g/min versus 15.3+/-1.1 mL/100 g/min) at 5 hours posthematoma (or any other posthematoma measurement) compared with prehematoma values. No changes were observed in cerebral glucose utilization, lactate production, and rCBF in other regions after introduction of ICH. Permeability of the blood-brain barrier was more prominent in the ipsilateral hemisphere in animals with ICH compared with control animals. CONCLUSIONS: Despite a prominent increase in ICP and MAP after ICH, the authors found no evidence to support the presence of an ischemic penumbra in the first 5 hours after ICH. Thus, other mechanisms for acute neural injury and late rCBF changes after ICH must be investigated.

Animals↗
PubMed1998

Determination of the antitumor agent depsipeptide in plasma by liquid chromatography on serial octadecyl stationary phases.

A high-performance liquid chromatographic assay has been developed and validated for the determination of the antitumor agent depsipeptide (FR-901228) in plasma samples from patients with advanced cancer. After the plasma proteins were precipitated with acetonitrile, the supernatant was extracted with ethylacetate. Depsipeptide was chromatographed on two serial octadecylsilica stationary phases using a mobile phase consisting of acetonitrile-potassium phosphate buffer (0.03 M, pH 3) (27:73, v/v), at a flow-rate of 2.0 ml/min and at ambient temperature. The method was linear over a 50 to 2000 ng/ml range and the intra- and inter-day coefficients of variations were less than 8%. The method was applied to the determination of the plasma concentration-time profile for 14 patients with advanced cancer receiving from 1 to 7.5 mg/m2 of depsipeptide per day as a continuous 4-h infusion.

Anti-Bacterial Agents↗
PubMed2006

Antimicrobial, resistance-modifying effects, antioxidant and free radical scavenging activities of Mezoneuron benthamianum Baill., Securinega virosa Roxb. &Wlld. and Microglossa pyrifolia Lam.

Mezoneuron benthamianum, Securinega virosa and Microglossa pyrifolia are used in folk medicine in Ghana for the treatment of dermal infections and wounds. Petroleum spirit, chloroform and ethanol extracts of the plants were tested for antimicrobial activity against a battery of organisms using the agar well diffusion technique and a serial dilution microassay. The resistance modifying activities of these extracts on standard antibiotics against Staphylococcus aureus possessing efflux mechanisms of resistance have also been assessed. A 4-fold potentiation of the activity of norfloxacin was observed for ethanol and chloroform extracts of M. benthamianum and S. virosa, respectively, whilst the petroleum spirit extract resulted in a 2-fold potentiation with minimum inhibitory concentration (MIC) values in the range 8-16 microg/mL. Ethanol extracts of all three species, the petroleum spirit extract of M. benthamianum and the chloroform extracts of M. benthamianum and S. virosa, showed interesting antimicrobial activities. Antioxidant and free radical scavenging activities using DPPH spectrophotometric and TBA lipid peroxidation assays were also conducted. Of the five extracts that showed antioxidant activities, the petroleum spirit and chloroform extracts of M. benthamianum rated most highly by displaying strong free radical scavenging activity with IC50 values of 15.33 and 19.72 microg/mL, respectively. Lipid peroxidation inhibition provided by the same two extracts also produced the lowest IC50 values for all the extracts tested, of 23.15 and 30.36 microg/mL. These findings therefore give some support to the ethnopharmacological use of the plants in the treatment of various skin diseases and wounds, as well as demonstrating the potential of some of the plants as sources of compounds possessing the ability to modulate bacterial multidrug resistance.

Animals↗
PubMed1990

[On eruption of mandibular third molar after extraction of mandibular first or second molar].

In the orthodontic practice, the first or second molars are extracted by reason of a necessity based on the treatment planning. In these cases, it is desirable that the third molar would be taken part in the masticatory function. This study was made to investigate the natural movement of the erupting third molars after the extraction of the first or second molar on the serial lateral cephalometric radiographs and orthopantomographs. Subjects were divided into three groups. The first is the group which the mandibular second molars were extracted. The second is the group which the first molars were extracted bringing about the successful eruption of the third molars. The third is the group which the first molars were extracted with resultant in the failure of the third molar eruption. In all cases, the orthodontic forces were not applied to the third molars. The results were as follows: 1. In the first group, all third molars were successfully erupted and a lot of the spaces after the extraction of second molars were utilized for the eruption of third molars. 2. In the second group, all third molars were successfully erupted and a lot of the spaces after the extraction of first molars were utilized for the mesial movement of the second molars. 3. In the third group, there were various patterns of the impaction of the third molars. It was suggested that the eruption of the third molar was related to the space distal to the second molar but it was not related to the anterio-posterior length of the mandibular body significantly.

Cephalometry↗
PubMed1998

Relation of urokinase-type plasminogen activator expression to presence and severity of atherosclerotic lesions in human coronary arteries.

Urokinase-type plasminogen activator (UPA) has been implicated in a broad spectrum of pathological processes - e.g. cell adhesion, migration and proliferation and matrix remodeling - that are considered important features of atherogenesis and plaque disruption. In this study, we have analyzed the content and expression of UPA in human coronary arteries and its relation to the presence and severity of atherosclerotic lesions. Segments of coronary arteries obtained from human heart explants (n = 15) were classified by the presence and types of atherosclerotic lesions. UPA was quantitatively determined in protein extracts of the intimal and medial layers. In situ hybridization and immunohistochemical analyses were performed on serial sections of representative tissue specimens. UPA was detected in the extracts as pro-UPA, UPA complexed to plasminogen activator inhibitor-1, or as otherwise inactive UPA antigen, but not in the active two-chain form. Both functional and total UPA were increased several-fold in extracts of advanced lesions, while the ratios of functional over total UPA showed the opposite trend suggesting enhanced UPA inactivation and turnover. UPA expression in early atherosclerotic lesions was particularly prominent in areas of proliferating SMCs in the abluminal part of the neointima, whereas in advanced lesions UPA was widely expressed in macrophage-rich areas adjacent to the rims and shoulder regions of the necrotic cores. The results strongly suggest a causal involvement of UPA in coronary atherogenesis and its clinical outcome.

Coronary Artery Disease↗
PubMed1981

Comparison of renal extraction efficiencies for radioactive agents in the normal dog.

The renal extraction efficiencies for various radioactive agents were measured in normal anesthetized dogs during 1 hr after a single intravenous injection. Radioassays were made on serial blood samples drawn simultaneously from the aorta upstream from the renal arteries and from one renal vein. As a reference substance [131I]o-iodohippurate was injected concurrently in all experiments. Blood clearances from serial venous samples and urinary excretion also were measured. Extraction efficiency from whole blood was calculated as (A-V) divided by A, where A = aortic concentration and V = renal venous concentration. This ratio for commercial [131I]o-iodohippurate fell steadily from 88% at 30 sec to 50% at 1 hr. For "purified" [131I]o-iodohippurate the fall was less marked, to 61% at 1 hr. The EE ratios for all other agents were stable after the first minute. The Tc-99m complexes of DTPA, glucoheptonate, and acetylcysteine had ratios averaging 27-29%. The ratios of Tc-99m DMS and Hg-197 chlormerodrin had much lower average values of 8 and 14%, respectively. None of the newer agents approached the extraction efficiency of [131I]o-iodohippurate.

Animals↗
PubMed2004

Spasmogenic effect of a Solanummelongena leaf extract on guinea pig tracheal chains and its possible mechanism(s).

The methanol extract of fresh leaves of Solanum melongena L. (Solanaceae) was evaluated for its capacity to alter the tone of isolated, pre-contracted guinea pig tracheal chains, as well as for its possible mechanism(s) of action. Using serial dilutions between 0.0025 and 2.5 mg/mL, the extract was found to cause a dose-dependent increase in the force of muscle contraction. The EC(50) value was 0.46 +/- 0.01 mg/mL. The concomitant use of acetylcholine 10(-5) M did not significantly affect the force of contraction induced by the extract. Histamine 10(-5) M added at about 40% to, and salbutamol 10(-6) M antagonized by about 30% its constrictive effect. Chlorpheniramine 10(-6) M, propanolol 10(-5) M, and nifedipine 10(-6) M did not significantly influence the extract-induced force of contraction, but atropine 3 x 10(-7) M reduced it by approximately 60%. These data suggest that the Solanum melongena extract exerted a bronchospasmogenic rather than a bronchospasmolytic effect, probably through muscarinic receptor stimulation.

Acetylcholine↗
PubMed2001

Antibacterial activity of Marula (Sclerocarya birrea (A. rich.) Hochst. subsp. caffra (Sond.) Kokwaro) (Anacardiaceae) bark and leaves.

Marula bark is widely used for bacteria-related diseases by indigenous cultures in Africa. This study was undertaken to investigate whether the ethnobotanical use can be validated by laboratory studies. Bark and leaves were extracted with acetone and MIC values were determined using a microplate serial dilution technique with Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis as test organisms. All extracts were active with MIC values from 0.15 to 3 mg/ml. Based on minimum inhibitory concentration values, inner bark extracts tended to be the most potent followed by outer bark and leaf extracts, but the differences were not statistically significant. There were two major bioactive components visible after bioautography of leaf extracts: one strongly polar and the other highly non-polar. The bioactive components could be separated from 92% of the non-active dry matter by solvent-solvent fractionation into the carbon tetrachloride, chloroform and n-butanol fractions; these fractions, however, still contained many different compounds. Using bark may be detrimental to the plant, but leaf material can also be used for antibacterial application.

Bacterial Infections↗
PubMed1979

Phylogenetic and anatomical distribution of somatostatin in vertebrates.

Immunoreactive GH release-inhibiting factor [somatostatin (SRIF)] was detected in hypothalamus, extrahypothalamic brain, pancreas, and stomach extracts of the rat, pigeon, tortoise, frog, teleost (cichlid), and elasmobranch (dogfish) and in the whole brain of the cyclostome (hagfish). The SRIF concentration was higher in the pancreas and gastrointestinal tract than in the hypothalamus and extrahypothalamic brain in most species. Extracts of the various tissues from the different species assayed in serial dilutions gave displacement curves parallel to those of synthetic mammalian SRIF. Cation exchange chromatography of hypothalamic extracts from the various species revealed two major immunoreactive peaks, one of which correpsonds to synthetic SRIF in elution volume, the other being less basic. Affinity chromatography-purified immunoreactive SRIF from frog brain, pancreas, and stomach extracts coeluted with synthetic SRIF in high pressure liquid chromatography. The results indicate that immunoreactive SRIF in various tissues and in different vertebrates is indistinguishable and suggest that there has been no change in the molecule during at least 400 million yr of evolution.

Animals↗