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Biomedical subjects

H N elSohly

Publications and source records attributed to H N elSohly.

12 recordsLinked to original sources
PubMed2001

Dihydrochalcones from Piper longicaudatum.

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).

Alkaloids↗
PubMed2000

7-Caffeoylsedoheptulose from Nyssa sylvatica.

7-Caffeoylsedoheptulose has been isolated from the wood of Nyssa sylvatica, along with two ellagic acid derivatives and scopoletin. Its structure was established by chemical and spectral evidence.

Chromatography, High Pressure Liquid↗
PubMed1994

Taxol content of stored fresh and dried Taxus clippings.

The taxol content of dried Taxus biomass was monitored monthly for 15 months. Intact and finely ground biomass was stored at room temperature (22 degrees-24 degrees) as well as under refrigeration (2 degrees-4 degrees). In addition, intact fresh clippings stored under refrigeration in sealed plastic bags for up to 10 weeks were evaluated for changes in taxol content. Analysis indicates that properly dried Taxus clippings can be stored either intact or powdered at room temperature or under refrigeration with no apparent loss of taxol content. The taxol content in fresh intact clippings was also stable for at least 10 weeks when stored under refrigeration.

Biomass↗
PubMed1990

Synthesis and antimalarial activity of (+)-deoxoartemisinin.

(+)-Deoxoartemisinin (2), a new and more active antimalarial agent, was successfully prepared from artemisinin in one step using NaBH4 and BF3.Et2O in THF. (-)-Deoxodeoxyartemisinin (5), a potential metabolite of deoxoartemisinin, was also prepared either from 2 or from artemisinic acid. 2 shows 8-fold increased antimalarial activity in vitro against chloroquine-resistant malaria as compared to artemisinin (1). Compound 2 possesses superior in vivo antimalarial activity to 1.

Animals↗
PubMed1988

Gas chromatographic/mass spectrometric analysis of morphine and codeine in human urine of poppy seed eaters.

In this study, poppy seeds were examined for a natural constituent that might serve as a maker for the seeds' ingestion as opposed to opiate abuse. Thebaine was selected as possible marker, since it was found to be a component of all poppy seeds examined and was not a natural component of different heroin samples. During the course of this investigation, a new extraction and cleanup procedure was developed for the gas chromatographic/nitrogen phosphorus detection (GC/NPD) and gas chromatographic/mass spectrometric (GC/MS) analysis of morphine and codeine in urine. A linear response, over a concentration range of 25 to 600 ng/mL, was obtained for codeine and morphine (r = 0.9982 and 0.9947, respectively). The minimum detectable level (LOD) and limit of quantitation (LOQ) for morphine were 10 and 30 ng/mL, respectively; whereas LOD and LOQ for codeine were 2 and 8 ng/mL, respectively. The coefficients of variance (CV, n = 6) for morphine and codeine analyses at the 100-ng/mL level were 13.3 and 4.6%, respectively. This procedure was used for the analysis of urine samples from five poppy seed eaters who each ingested 200 g of poppy seed cake. Results indicated that significant amounts of morphine and codeine are excreted in urine and that in all subjects, at least at one point in time, the apparent morphine concentration as determined by radioimmunoassay (RIA) analysis exceeded the cutoff value (300 ng/mL) established for screening. Thebaine was not detected in urine specimens collected following poppy seeds ingestion and thus could not be used as a marker.

Chromatography, Gas↗
PubMed1987

The effect of subacute marijuana smoke inhalation on experimentally induced dermonecrosis by S. aureus infection.

Dermonecrosis was induced in ICR mice by subcutaneous implantation of Staphylococcus aureus absorbed onto sterile cotton pellets. This model was used to assess the effects of marijuana smoke, marijuana placebo smoke and delta 9-tetrahydrocannabinol (delta 9-THC) on the local immune response to bacterial infection. Mice were exposed to 40 or 80 "puffs" of marijuana smoke, marijuana placebo smoke or air daily for 4 consecutive days. The estimated dose of delta 9THC per day generated from 40 or 80 puffs of marijuana smoke was 3.2 and 6.4 mg/kg, respectively. A group of sentinel (Shelf) control mice were included in each experiment. The necrotic index (NI) of mice exposed to 40 or 80 puffs of marijuana smoke were 67% and 44% of control, respectively. Air exposed mice showed a necrotic index comparable to the shelf control group. In chronically (60 days) exposed mice (80 puffs per day) the necrotic index was about 12% of control, while air-exposed mice were about 40% of control. Placebo marijuana smoke exposed mice had a NI comparable to that of marijuana smoke exposed mice which suggested that the reduction in NI was unrelated to the pychomimetic component delta 9THC. To further explore which of the constituents of marijuana were responsible for the decreased NI, the ethanol extract from marijuana leaves was partioned between water (cannabinoid free) and chloroform (cannabinoid rich). Injection of the cannabinoid free fraction produced comparable decrease in the NI as observed with whole marijuana smoke, while the cannabinoid rich fraction produced no effect. delta 9THC at a dose of 10 mg/kg per day did not alter the NI.

Animals↗
PubMedDate not supplied

Microbial metabolism studies of the antimalarial sesquiterpene artemisinin.

Microbial metabolism of the sesquiterpene lactone antimalarial drug artemisinin [1] was studied. Screening studies have shown a number of microorganisms capable of metabolizing artemisinin [1]. Scale-up fermentation with Nocardia corallina (ATCC 19070) and Penicillium chrysogenum (ATCC 9480) have resulted in the production of two major microbial metabolites that have been characterized with the use of 2D-nmr techniques. These metabolites have been identified as deoxyartemisinin [2] and 3 alpha-hydroxydeoxyartemisinin [3].

Antimalarials↗
PubMedDate not supplied

Poppy seed ingestion and opiates urinalysis: a closer look.

Review of scientific literature shows that ingestion of poppy seed containing products can result in a positive urinalysis test for opiates. In many cases the amount of seeds ingested is unrealistically high or is not specified. This study is designed to correlate the amount of seeds ingested with the urinary concentration of total morphine as a function of time. Two males and two females were involved in all four protocols, which were separated by at least one week. Subjects ingested one, two, or three poppy seed rolls, each containing 2 g of Australian seeds (108 micrograms morphine/g seed) in three protocols. In the fourth protocol subjects ingested two rolls per day for four consecutive days. Urine specimens were collected for 48 h after ingestion, analyzed by RIA, EMIT, and TDx, and selected samples were confirmed by GC/MS. The data show that the highest concentrations of total morphine in urine were found 3-8 h after ingestion or in the first-void samples. Of the 264 samples collected, there were only 16 specimens that exceeded 300 ng/mL by any of the methods used for analysis with only three samples exceeding 400 ng/mL by GC/MS (406, 611, and 954 ng/mL). In all cases, the total opiates level was less than 150 ng/mL 24 h after ingestion. Following these studies, one of the subjects ingested a poppy seed cake containing 15 g seed obtained from a bakery which analyzed for 169 micrograms morphine/g seed. Urine specimens were collected over 48 h, and all specimens were analyzed by GC/MS.(ABSTRACT TRUNCATED AT 250 WORDS)

Codeine↗