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PubMed2000

Improved controlled release study of lomustine.

Lomustine (CCNU) microcapsules was prepared by improved recoacervation method, then mixed microcapsules with 0.7% collagen swelling solution to prepare the emulsion, spreaded the emulsion on the plate to form membrane and cross-linked it, the membrane would be planted into body and was expected to release at steady speed. The concentration of CCNU and the CCNU content of microcapsules were measured by ultraviolet spectrophotometry to observe the release of CCNU be slow and constant, approach to 0-class release approximately.

Absorbable Implants↗

PubMed1975

Thiopental suicide -- case report.

Thiopental was indicated in the suicide death of a hospital employee. The blood thiopental level was determined to be 27.9 mg% by ultraviolet spectrophotometry, and positive identification was accomplished using gas chromatography, thin-layer chromatography, and infrared spectrophotometry.

Adult↗

PubMed1977

Laboratory support of drug abuse control programs: an overview.

Labeling an individual a drug abuser has serious sociologic and legal implications that only laboratory testing can effectively allay. A proper specimen (both qualitatively and quantitatively) must be obtained for analysis. Positive identification of specimen with subject is of paramount importance. The problems of specimen substitution--other people's urine, tap water, apple juice--directly impinge here, as does the possibility of drug degradation by heat, light, and microbial attack and of drug adsorption by the container and urinary sediment. Confirmation of postives indicated by screening tests (thin layer chromatography and immunoassays) by gas chromatography and/or ultraviolet spectrophotometry is, in most situations, mandatory. An effective quality control program is an absolute requirement. Even under ideal circumstances, laboratory results can sometimes wrongly indicate the abuse of drugs; and conversely, drug abuse can take place without detection by the laboratory. As in any clinical situation, laboratory tests are only a part (albeit an important one) of the entire evaluation of the individual involved.

Chemistry, Analytic↗

PubMed1979

3,4-methylenedioxyamphetamine overdose.

MDA was indicated in the death of a 35-year-old male. Blood, tissue, and urine concentrations of MDA were measured by ultraviolet spectrophotometry after identification by gas chromatography/mass spectrometry. The concentrations found were within the range of previously reported fatal MDA levels.

3,4-Methylenedioxyamphetamine↗

PubMed1991

Uterine calcium-binding protein activity of nonlaying hens and hens laying hard-shelled or shell-less eggs.

Uterine calcium-binding protein (CaBP) activity was compared at oviposition and 14 h postoviposition in nonlaying (NL) hens and hens laying a high incidence of shell-less (SL) or hard-shelled (HS) eggs fed a commercial laying diet. Epithelial cells were removed from uteri of NL, SL, and HS hens and homogenized in Tris buffer, pH 7.4. Proteins in homogenate were fractionated by the addition of ammonium sulfate and centrifugation, separated by Sephadex chromatography, and measured by ultraviolet spectrophotometry at A280. Calcium-binding protein activity was determined using a 45Ca-chelex binding assay. Two peaks of CaBP activity were detected and designated CaBP-a (28,000 Da) and CaBP-b (16,000 Da). Uterine CaBP-b may differ from CaBP-a only in Ca content. The activities of CaBP (a and b) were higher (P less than or equal to .05) in HS and SL hens than in NL hens at 0 h. There was no significant difference (0 h) between CaBP activity (a versus b) of either HS or SL hens. There was also no difference (0 h) of CaBP-a or CaBP-b activity when SL and HS hens were compared. Uterine CaBP-a activity was lower (P less than or equal to .05) in SL hens than HS hens at 14 h. Under normal dietary conditions, the level of CaBP activity at 14 h may be associated with SL egg production.

Animals↗

PubMed2006

Phenolic acids in Fructus Xanthii and determination of contents of total phenolic acids in different species and populations of Xanthium in China.

OBJECTIVE: To study the chemical constituents of Fructus Xanthii and to determine the contents of total phenolic acids (TPA) in fruits of Xanthium from different populations for evaluating the quality of them. METHODS: Components in Fructus Xanthii were isolated and purified by various column chromatographies and the contents of TPA were determined by ultraviolet spectrophotometry with chlorogenic acid (CHA) as reference substance. RESULTS: Six caffeoylquinic acids along with caffeic acid and ferulic acid were isolated from Fructus Xanthii. The contents of TPA of the samples collected from 29 populations in China varied from 0.31% to 1.44%. Among the samples originated from two species and 1 variety of Xanthium, the contents of TPA in X. sibiricum var. subinerme samples with an average of 0.36% were relatively lower than those in other 2 species. While the content of TPA in Sample 3 collected from Shanghai was 1.44% and the highest among all the samples, and that in Sample 12 from Xinjian of Jiangxi Province was 0.38% and the lowest among the X. sibiricum samples. CONCLUSION: 5-O-caffeoylquinic acid, 1,4-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid were isolated from Xanthium plant for the first time. The difference of contents of TPA in samples from different species and different populations in China was relatively significant. Fructus Xanthii in Shanghai and Sanming of Fujian Province were considered high quality if contents of TPA were used as reference for quality evaluating.

Caffeic Acids↗

PubMed2005

Protective role of metallothionein in stress-induced gastric ulcer in rats.

AIM: To illustrate the pathophysiological role of metallothionein (MT) in gastric ulcer induced by stress. METHODS: Wistar rats underwent water-immersion-restraint (WIR) stress, ZnSO(4) (an MT inducer) treatment, WIR+ZnSO(4) or WIR+MT, and the ulcer index (UI) was estimated in excised stomach and liver tissues. The mRNA level of gastric MT was determined by semi-quantitative RT-PCR. The MT content in gastric and hepatic tissues was determined by Cd/hemoglobin affinity assay. The lipid peroxidation products malondialdehyde (MDA) and conjugated dienes (CD) were estimated by use of thiobarbituric acid reactive species and ultraviolet spectrophotometry. RESULTS: WIR stress induced severe gastric mucosal lesions in rats. Compared with control rats, stressed rats had increased lipid peroxide content in serum and stomach and liver tissues. MDA content was increased by 34%, 21% and 29% and CD level by 270%, 83% and 28%, respectively. MT content in the stomach and liver was increased by 0.74- and 1.8-fold, and the MT-mRNA level in the stomach was increased by 26%. Pretreatment with ZnSO(4) prevented gastric lesion development (the UI was 87% lower than that without pretreatment), and the MDA and CD content in serum and tissues was lower. The MT content in the liver was double in rats that were not pretreated, and the MT mRNA level in the stomach was 35% higher. MT administration 1 h before the WIR stress prevented gastric lesion development (the UI decreased by 47% compared with that in rats not pretreated), and the MDA and CD content in serum and tissues was significantly lower. CONCLUSION: In WIR-stressed rats, the MT level was increased in serum and in stomach and liver tissues. Pre-administration of exogenous MT or pre-induction of endogenous MT can protect the gastric mucosa against stress-induced ulcers and inhibits the formation of stress-induced lipid peroxide. MT could have a gastroprotective effect and might be a new interventive and therapeutic target in stress-induced gastric ulcers.

Animals↗

PubMed2005

Protective effect of Radix Acanthopanacis Senticosi capsule on colon of rat depression model.

AIM: To investigate the abnormity of rat colon caused by depression and the ameliorative effects of Radix Acanthopanacis Senticosi (RAS) capsule on colon and their mechanisms in rat depression model. METHODS: Chronic stress-induced model of depression of Wistar rats was produced. The experimental animals were randomly divided into model control, 5-aminosalicylic acid (5-ASA) therapy group and three RAS capsule therapy groups. These five groups were intracolonically treated daily (8:00 a.m.) for 2 wk with normal saline, 5-ASA (100 mg/kg) and RAS capsule at the doses of 300, 600 and 900 mg/kg, respectively. A normal control group of rats was also included in the study. Colonic activities of nitric oxide (NO) and superoxide dismutase (SOD), levels of malondialdehyde (MDA) and inducible nitric oxide synthase (iNOS) were determined by ultraviolet spectrophotometry. The expression of cyclooxygenase-2 (COX-2) in colonic tissue was detected by immunohistochemistry. RESULTS: Enhanced colon inflammatory response and oxidative stress were observed in the chronic stress-induced rat depression model, which manifested as the significant increase of MDA, iNOS and NO levels, as well as the expressions of COX-2 in the colon tissue, but the colonic SOD activity was significantly decreased compared with the normal control (MDA: 10.34+/-2.77 vs 2.55+/-0.70; iNOS: 1.11+/-0.44 vs 0.25+/-0.16; COX-2: 53.26+/-8.16 vs 4.87+/-1.65; NO: 11.28+/-5.66 vs 4.76+/-1.55; SOD: 53.39+/-11.15 vs 84.45+/-22.31; P < 0.01). However, these parameters were significantly ameliorated in rats treated locally with RAS capsule at the doses of 300, 600 and 900 mg/kg (iNOS: 0.65+/-0.31, 0.58+/-0.22 and 0.64+/-0.33; NO: 5.99+/-2.73, 6.87+/-1.96 and 6.50+/-1.58; MDA: 2.92+/-0.75, 3.19+/-1.08 and 3.26+/-1.24; SOD: 70.81+/-12.36, 73.30+/-15.30 and 69.09+/-11.03, respectively). The expressions of COX-2 in the colon were significantly ameliorated (28.83+/-9.48 and 27.04+/-9.56, respectively) when RAS capsule was administered at the doses of 600 and 900 mg/kg. CONCLUSION: Administration of RAS capsule intracolonically may have significant therapeutic effects on the colon of rat depression model, which are probably due to its antioxidative action and inhibition of arachidonic acid metabolism.

Animals↗

PubMed2003

Ameliorative effects of sodium ferulate on experimental colitis and their mechanisms in rats.

AIM: To investigate the ameliorative effects of sodium ferulate (SF) on acetic acid-induced colitis and their mechanisms in rats. METHODS: The colitis model of Sprague-Dawley rats was induced by intracolon enema with 8% (V/V) of acetic acid. The experimental animals were randomly divided into model control, 5-aminosalicylic acid therapy group and three dose of SF therapy groups. The 5 groups were treated intracolonically with normal saline, 5-aminosalicylic acid (100 mg x kg(-1)), and SF at the doses of 200, 400 and 800 mg x kg(-1) respectively and daily (8:00 am) for 7 days 24 h following the induction of colitis. A normal control group of rats clystered with normal saline instead of acetic acid was also included in the study. Pathological changes of the colonic mucosa were evaluated by the colon mucosa damage index (CMDI) and the histopathological score (HS). The insulted colonic mucosa was sampled for a variety of determinations at the end of experiment when the animals were sacrificed by decapitation. Colonic activities of myeloperoxidase (MPO) and superoxide dismutase (SOD), and levels of malondialdehyde (MDA) and nitric oxide (NO) were assayed with ultraviolet spectrophotometry. Colonic contents of prostaglandin E2 (PGE2) and thromboxane B2 (TXB2) were determined by radioimmunoassay. The expressions of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2) and nuclear factor kappa B (NF-kappaB) p65 proteins in the colonic tissue were detected with immunohistochemistry. RESULTS: Enhanced colonic mucosal injury, inflammatory response and oxidative stress were observed in the animals clystered with acetic acid, which manifested as the significant increase of CMDI, HS, MPO activities, MDA and NO levels, PGE2 and TXB2 contents, as well as the expressions of iNOS, COX-2 and NF-kappaB p65 proteins in the colonic mucosa, although the colonic SOD activity was significantly decreased compared with the normal control (CMDI: 2.9+/-0.6 vs 0.0+/-0.0; HS: 4.3+/-0.9 vs 0.7+/-1.1; MPO: 98.1+/-26.9 vs 24.8+/-11.5; MDA: 57.53+/-12.36 vs 9.21+/-3.85; NO: 0.331+/-0.092 vs 0.176+/-0.045; PGE2: 186.2+/-96.2 vs 42.8+/-32.8; TXB2: 34.26+/-13.51 vs 8.83+/-3.75; iNOS: 0.365+/-0.026 vs 0.053+/-0.015; COX-2: 0.296+/-0.028 vs 0.034+/-0.013; NF-kappaB p65: 0.314+/-0.026 vs 0.039+/-0.012; SOD: 28.33+/-1.17 vs 36.14+/-1.91; P<0.01). However, these parameters were found to be significantly ameliorated in rats treated locally with SF at the given dose protocols, especially at 400 mg x kg(-1) and 800 mg x kg(-1) doses (CMDI: 1.8+/-0.8, 1.6+/-0.9; HS: 3.3+/-0.9, 3.1+/-1.0; MPO: 63.8+/-30.5, 36.2+/-14.2; MDA: 41.84+/-10.62, 37.34+/-8.58; NO: 0.247+/-0.042; 0.216+/-0.033; PGE2: 77.2+/-26.9, 58.4+/-23.9; TXB2: 18.07+/-14.83; 15.52+/-8.62; iNOS:0.175+/-0.018, 0.106+/-0.019; COX-2: 0.064+/-0.018, 0.056+/-0.014; NF-kappaBp65: 0.215+/-0.019,0.189+/-0.016; SOD: 32.15+/-4.26, 33.24+/-3.69; P<0.05-0.01). Moreover, a therapeutic dose protocol of 800 mg x kg(-1) SF was observed as effective as 100 mg x kg(-1) of 5-ASA in the amelioration of colonic mucosal injury as evaluated by CMDI and HS. CONCLUSION: Administration of SF intracolonically may have significant therapeutic effects on the rat model of colitis induced by acetic acid enema, which was probably due to the mechanism of antioxidation, inhibition of arachidonic acid metabolism and NF-kappaB expression.

Acetic Acid↗

PubMed1999

[Are ultraviolet and visible spectroscopy and spectrophotometry obsolete methods in pharmaceutical analysis?].

It has been investigated if UV-VIS spectroscopy and spectrophotometry can be regarded to be obsolete methods in pharmaceutical analysis. The conclusions are as follows. As a consequence of the introduction and spreading of highly efficient spectroscopic methods in the structural analysis of organic compounds the importance of UV-VIS spectroscopy as a structure elucidation tool has greatly decreased. At the same time, however, diode-array UV spectrophotometers used as HPLC detectors have created very convenient possibilities for the identification of minor components (impurities, degradation products, etc.) in drugs. This statement is illustrated by several practical examples. On the basis of some data taken from the British Pharmacopoeia 1998 it is stated that UV spectrophotometry as a quantitative analytical method still belongs to the most frequently used analytical techniques in pharmaceutical analysis. At the same time, however, the authors are of negative opinion about the up-to-dateness and usefulness of colorimetric methods still very often published for the determination of drug substances.

Colorimetry↗

PubMed1999

Detection of substandard fixed-dose combination tuberculosis drugs using thin-layer chromatography.

SETTING: A convenience sample of 13 fixed-dose combination (FDC) tuberculosis (TB) drugs from 'The Fixed Dose Combination Project' was analysed in laboratories at the University of Botswana and the US Food and Drug Administration (FDA). OBJECTIVE: To determine actual versus stated content of drugs in these FDCs. DESIGN: Chemical analysis was performed using thin-layer chromatography (TLC) as a screening method, and ultraviolet (UV) spectrophotometry or liquid chromatography (LC) as confirmation. FDCs with content outside of 85-115% of stated concentration were defined as substandard. RESULTS: All 13 FDCs contained the stated drugs. However, four (31%) were substandard, including two (15%) with low rifampicin content, one (8%) with excessive rifampicin, and one (8%) with excessive pyrazinamide. Both FDCs with low rifampicin contained four drugs and failed TLC screening. The FDC with excessive rifampicin was not detected by TLC screening. Using UV as the gold standard, the sensitivity of TLC for low rifampicin was 2/2 (100%), and the specificity was 9/10 (90%). CONCLUSION: This study found that 31% of the FDCs in 'The Fixed Dose Combination Project' had substandard content, irrespective of bioavailability. Low rifampicin content, which can be reliably detected by TLC screening, was identified in both four-drug FDC products and is particularly worrisome. TB drugs should be screened for quality using TLC to optimise treatment outcomes and to prevent increases in acquired drug resistance.

Antitubercular Agents↗

PubMedDate not supplied

Rapid ultraviolet spectrophotometric and liquid chromatographic methods for the determination of natamycin in lactoserum matrix.

Two rapid and simple methods were developed for the determination of natamycin in lactoserum matrix by ultraviolet (UV) spectrophotometry and liquid chromatography (LC) with diode-array detection. The methods involve protein precipitation with methanol, followed by centrifugation. No cleanup is necessary. The applicable concentrations of natamycin in lactoserum range from 2 to 500 mg/L for samples analyzed by both methods. The detection and quantitation limits are 0.07 and 0.23 mg/L, respectively, for the UV spectrophotometric method and 0.1 and 0.32 mg/L, respectively, for the LC method. The methods were applied satisfactorily to the determination of natamycin in various commercial lactosera. Both methods were validated independently by standard additions and Youden methodologies, which verified their accuracy. Once the 2 proposed methods were validated independently, the validation of one method was carried out with the other.

Antifungal Agents↗

PubMed2001

[The inducibility of Amp C enzyme of Enterobacter cloacae and its susceptibility to enzyme inhibitor].

OBJECTIVE: To study the inducibility of Amp C enzyme of Enterobacrter cloacae and its susceptibility to enzyme inhibitor. METHODS: The in vitro activities of the fourth generation cephalosporins-cefepime, the third generation cephalosporins-cefuroxime, cefotaxime, ceftazidime combined with beta-lactamase inhibitor sulbactam against 10 strains of ceftazidime resistant Enterobacter cloacae selected from the hospitals was studied with agar two fold dilution method. The inducibility of beta-lactam antibiotics in common use clinically to Amp C enzyme and the inhibitory action of 3 inhibitors to Amp C enzyme were studied with ultraviolet spectrophotometry and RTPCR. RESULTS: Sulbactam can not enhance the activity of ceftazidime against Enterobacter cloacae. Cefepime has a strong activity against ceftazidime resistant Enterobacter cloacae. Imipenem has a strong inductive action to Amp C enzyme. Ro481220 has a strong inhibitory action to Amp C enzyme. CONCLUSION: Infections caused by Enterobacter cloacae producing Amp C enzyme can be treated by cefepime.

Bacterial Proteins↗

PubMed1999

[Studies on stimulating components of raw Pinellia ternata (Thunb.) (banxia)].

OBJECTIVE: To study the stimulating components of raw Pinellia ternata (Banxia). METHODS: Used the methods of extracting with various organic solvents; x-ray fluorescence spectrometer; scanning electron microanalyzer; oxidation and reduction titrations; and ultraviolet spectrophotometry. RESULTS: Experiments showed that calcium oxalate hydrate (C2CaO4 x H2O) was one of the stimulating components of raw Pinellia ternata, and its shape, and contents related to the stimulation of raw Pinellia ternata. After processing, the shape and contents of calcium oxalate changed, decreased respectively, and the stimulation of Pinellia ternata decreased. CONCLUSION: The needle crystal of calcium oxalate is one of the stimulating components in raw Pinellia ternata.

Animals↗

PubMed2002

In vitro deposition of the respirable fraction of dry powder inhalations determined by laser diffractometry and inertial impaction.

Particle size analysis of drug and excipient is of particular interest for dry powder inhalation (DPI) formulations development and quality control. In this work, the deposition in the upper, the medium and the lower (i.e. the respirable fraction) Twin Impinger compartments of sodium cromoglycate (SCG), lactose (as excipient) and a 1:1 mixture thereof was determined by chemical analysis using a DPI device--the Micro-hale--and compared with the results obtained by laser diffractometry for the same fractions. The analytical method for the SCG determination consisted of ultraviolet spectrophotometry and, for the lactose, high performance liquid chromatography with refractive index detection was used. Laser diffractometry as a quickly operating routine method can substitute the chemical analysis in order to evaluate the respirable fraction, under the conditions of the present work and therefore making formulation development easier and quicker.

Administration, Inhalation↗

PubMed2002

Why certain dyes are useful for localizing the sentinel lymph node.

UNLABELLED: Location of the sentinel lymph node in malignant melanoma and early breast cancer patients requires separate injections of radiocolloid and blue dye. These agents are administered at alternative times because of their different rates of transit. This study has elucidated why particular dyes are absorbed by the lymphatic system from an investigation of dye molecular structure as a function of protein binding ability. METHODS: A dye-protein binding assay was developed using size-exclusion chromatography and ultraviolet spectrophotometry and applied to a series of 20 sulfonic acid group-containing dyes. Radiochemical analyses were also used with 3 99mTc-labeled dyes to rationalize which functional groups are involved in the protein binding reaction. RESULTS: Methylene blue resulted in no protein affinity at 37 degrees C, whereas disulfonate dyes separated by 1 atom such as Patent blue or Indigo carmine gave <30% binding. Optimum protein binding (84%-100%) was achieved with those dyes containing at least 2 sulfonic acid groups separated by 2-6 atoms in their chemical structure. Seven symmetric tetrasulfonic acid azo dyes were examined, including Evans blue, to result in 59%-71% binding. CONCLUSION: Ionizable groups (sulfonic acids) that are present in the structure of dyes are directly involved in dye-protein binding. At the molecular level, there is a sulfonation reaction between sulfonic acid dyes and amino groups on the protein surface to form sulfonamide complexes. This reaction shows how the soluble dyes Evans blue and Patent blue are trapped in lymph after subdermal injection during the sentinel node biopsy procedure.

Animals↗

PubMed2000

[Contents of general flavonoides in Epimedium acuminatum Franch. and its differently-processed products].

OBJECTIVE: Determining and comparing the contents of general flavonoides in four kinds of differently-processed products of Epimedium acuminatum. METHOD: Determining the contents by ultraviolet spectrophotometry. RESULT: The contents were found in the following seguence: unprocessed product, clearly-fried product, alcohol-broiled product, salt-broiled product, sheep-fat-broiled product. The average recovery rate was 96.01%, with a 0.74% RSD(n = 5). CONCLUSION: Heating causes the contents of general flavonoides in the processed products to decrease. These processed products are still often used in clinical treatment, for the reason that the adjuvant features certain coordinating and promoting functions. The study is to be pursued further.

Epimedium↗

PubMed2000

[Preparation and qualitative control of compound Dyclonine's suspending mixture].

The paper deals with the composition, preparation and qualitative control of compound Dyclonine's suspending mixture, one of gastroscopic mucomembranous anesthetics. The content of Dyclonine hydrochloride was detected by ultraviolet spectrophotometry. It shows that the average rate of recovery is 100.80%, RSD = 1.32%(n = 6). At room temperature, the appearance and content of the preparation are not changed in 0, 30, 180, 365 days respectively. The preparation is widely and successfully used in clinics with easy procedure and excellent stability.

Anesthetics, Local↗