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Biomedical subjects

M A Kaplan

Publications and source records attributed to M A Kaplan.

At least 19 recordsLinked to original sources
PubMed2005

Relationship between antitumor efficiency of photodynamic therapy with photoditasine and photoenergy density.

We studied the effect of photodynamic therapy with photoditasine at different protocols of photoenergy exposure on morphofunctional parameters of M-1 sarcoma. It was found that proliferative activity of tumor cells (evaluated by immunostaining for PCNA) nonlinearly decreases after exposure to 150, 300, and 600 J/cm2. The main form of cell death during the early period after photodynamic therapy was direct photocoagulation necrosis caused by destruction of sensitized cell structures and ischemic necrosis developing as a result of alteration of vascular network in the tumors. Photoenergy density was not essential for the intensity of induced apoptosis.

Animals↗
PubMed2005

Role of laser energy density for photodynamic therapy of radiation injuries of the skin.

The role of different laser energy densities used in photodynamic therapy in the reparation of radiation ulcers caused by X-ray exposure in a dose of 80 Gy was studied. Tissue reparation manifested differently at different laser energy densities. After photodynamic therapy at energy density of 0.1 J/cm2 the rate of healing was notably higher during early periods. After exposure at 5 and 40 J/cm2 acceleration of ulcer healing was observed 14 and more days after the treatment, indicating the emergence of another mechanism of photodynamic therapy effect. Laser energy density of 5 J/cm2 was the most effective for maximally complete healing of radiation ulcers.

Animals↗
PubMed2004

[Angioroentgenologic response of rat M-1 sarcoma to low-energy infrared laser irradiation at varying frequency].

After rats with sarcoma M-1 inoculated in the femur area were exposed to low-energy (0.54 mT1) infra-red laser irradiation, 100Hz, for 10 min, the number of contrast-enhanced vessels of tumor fell sharply as compared with controls. That effect lasted for almost 24 hrs. At 1kHz, the total-sum of diameters of such vessels still increased 24 hrs after the exposure. When at 10kHz, that index decreased, and by day 3 vascular pattern and diameter came back to normal in all experiments.

Animals↗
PubMed2001

Essential oil analysis of 10 Piperaceae species from the Brazilian Atlantic forest.

The volatile composition of ten Piperaceae species, comprising three genera (Ottonia, Piper and Peperomia) has been studied. The species were collected in a typical fragment of the Brazilian Atlantic forest, constantly being damaged by human action. The essential oils were obtained by hydrodistillation in a modified Clevenger-type apparatus and their analyses were performed by GC and GC/MS. Identification of the substances was made by comparison of mass spectra and retention indices with literature records. A great number of non-oxygenated monoterpenes and sesquiterpenes were identified. Most of these sesquiterpenes are derived from E,E-farnesyl-PP, suggesting a preference of these species to synthesize metabolites from this pathway. Arylpropanoids, although being common compounds produced by Piperaceae species, were not found in these oils.

Brazil↗
PubMed2001

Photosensitization and mutation induced in Escherichia coli and Saccharomyces cerevisiae strains by dorstenin, a psoralen analog isolated from Dorstenia bahiensis.

Dorstenin, 5-[3-(4,5-dihydro-5,5-dimethyl-4-oxo-2-furanyl)-butoxy]-7H-furo[3, 2-g] benzopyran-7-one, is a psoralen analog recently isolated from Dorstenia species (Moraceae). In order to characterize its biological activity, its photosensitizing and mutational properties were measured in wild-type E. coli and S. cerevisiae and also in strains carrying mutations which affect DNA repair. Compared to the high activities of psoralen and bergapten, dorstenin showed lower genotoxic effect.

5-Methoxypsoralen↗
PubMed2001

Effect of leaf essential oil from Piper solmsianum C.DC. in mice behaviour.

The essential oil from Piper solmsianum leaves and its major compound (sarisan) were tested to verify their influences upon mice behaviour. The essential oil was obtained by hydrodistillation in a modified Clevenger extractor and analysed by GC/ MS. This analysis revealed in the oil the presence of monoterpenes, sesquiterpenes and of arylpropanoids. The compound sarisan, a myristicin analogue, was isolated from the oil to perform the pharmacological tests. Emulsions of the oil and of sarisan (5.0 and 10.0% v/v) were used in the tests. Pentobarbital (30 mg/ kg s.c.) or diazepam (2.5 mg/ kg s.c.) were tested as standard drugs to verify depressant or anxiolytic effects, respectively. Both essential oil and sarisan showed to have exciting and depressant effects in the tested animals.

Akathisia, Drug-Induced↗
PubMed2000

Pharmaceutical relationships of three solid state forms of stavudine.

Three solid state forms of stavudine designated forms I, II and III have been identified and characterized. Forms I and II are anhydrous polymorphs whereas form III is hydrated and is pseudopolymorphic with forms I and II. Physico-chemical and thermodynamic properties of the three solid state forms have been characterized. Solid-state stability and potential for interconversion of the forms to aid in the selection of preferred form for development and commercialization has been studied. Conditions of recrystallization governing the formation of thermodynamically most stable polymorphic form I devoid of other forms was identified.

Anti-HIV Agents↗
PubMed2000

A C-glucosylflavone from leaves of Piper lhotzkyanum.

The dichloromethane fraction obtained from the methanolic extract of leaves of P. lhotzkyanum afforded a C-glucosylflavone (kaplanin) together with sakuranetin, methyl 4-methoxydihydroferulate and a mixture of methyl ferulate and dihydroferulate derivatives. Spectrometric methods were used to elucidate the structures of these compounds.

Anthracenes↗
PubMed2000

The stereochemistry of ledol from Renealmia chrysotrycha: an NMR study.

From the leaves of Renealmia chrysotrycha (Zingiberaceae), we isolated a sesquiterpene alcohol for which spectral data suggested the structure of a 10-aromadendranol. A meticulous NMR investigation, based mainly on vicinal proton-proton coupling constants and NOE interactions, and confirmed by a molecular mechanics calculation, established its relative stereochemistry as that of ledol. This finding resolves several recent literature ambiguities. Three known compounds (aromadendrene, cis-calamenene and palustrol) were also isolated.

Magnetic Resonance Spectroscopy↗
PubMed2000

Determination of somatic mutant frequencies at glycophorin A and T-cell receptor loci for biodosimetry of acute and prolonged irradiation.

Somatic mutant frequencies at glycophorin A (GPA) and T-cell receptor (TCR) loci were assessed. The dependence of the GPA mutant frequency on doses of acute and prolonged irradiation was shown. In the case of acute irradiation the GPA mutant frequency displayed a three-fold greater dose-related increase as compared to prolonged irradiation. A dose-dependent increase in the TCR variant frequency was found only in a group of subjects with recent exposures. In Chernobyl clean-up workers the TCR mutant frequency was significantly higher than in control non-irradiated individuals.

Case-Control Studies↗
PubMed2000

[The optimization of a plan for the photodynamic therapy of sarcoma M1 using photosens].

The study established the importance of optimal dosage, concentration and mode of administration of the drug Fotosens for the effectiveness of photodynamic therapy of tumor. Of similar importance is the interval between administration and irradiation to potentiate the drug's action. Failure to consider the latter factor may lower the effect dramatically or even reverse it. Experimental findings point to high antitumor potency of the drug. Preference should be given to injecting relatively low concentrations along the periphery of tumor, thus avoiding the undesirable cytostimulating effect and toxicity of Fotosens and saving on the drug. The potential of the treatment as a component of "white light" photodynamic therapy is discussed.

Animals↗
PubMed1999

Anthelmintic activity of the latex of Ficus species.

The latex of some species of Ficus (Moraceae) has been traditionally used as vermifuge in Central and South America. It has been accepted that anthelmintic activity is due to a proteolytic fraction called ficin. In the present study, the anthelmintic activity of the latex of Ficus insipida Willd. and Ficus carica L. has been investigated in NIH mice naturally infected with Syphacia obvelata, Aspiculuris tetraptera and Vampirolepis nana. The latex of F. insipida, administered by intragastric route in doses of 4 ml/kg/day during three consecutive days, were effective in the removal of 38.6% of the total number of S. obvelata, being inexpressive in the removal of A. tetraptera (8.4%) and segments of V. nana (6.3%). The latex of F. carica, administered in doses of 3 ml/kg/day, during three consecutive days, was effective in the removal of S. obvelata (41.7%) and it did not produce significant elimination of A. tetraptera (2.6%) and V. nana (8.3%). The observed high acute toxicity with hemorrhagic enteritis, in addition to a weak anthelmintic efficacy, do not recommend the use of these lattices in traditional medicine.

Animals↗
PubMed1999

Etiology of outpatient pediatric nondysenteric diarrhea: a multicenter study in the United States.

BACKGROUND: Few data have been published recently on the etiology of outpatient pediatric diarrhea in the US. METHODS: We determined the etiology of acute, nondysenteric diarrhea among 147 children between 2 and 11 years old presenting to 9 outpatient clinics in various regions of the US between August, 1991, and August, 1993. Enteropathogens were sought by conventional laboratory methods. The various diarrheagenic Escherichia coli were sought. RESULTS: A recognized etiologic agent was detected in the stools of 89 (60.5%) children and 15 (10) patients had multiple agents detected. Rotavirus was found in 43 (29.3%) of the children, with a spring and winter peak in occurrence. Giardia lamblia was identified in 22 (15%) cases with a spring peak. HEp-2 cell-adherent E. coli were found in 15 (10.2%). Other agents found included: enteric adenovirus in 7 (4.8%); Salmonella in 5 (3.4%); enterohemorrhagic E. coli in 5 (3.4%); enteropathogenic E. coli in 2 (1.4%); enterotoxigenic E. coli in 2 (1.4%); Entamoeba histolytica in 1 (0.70%); and Campylobacter jejuni in 1 (0.7%). CONCLUSIONS: In addition to the presence of conventional enteropathogens, diarrheagenic E. coli (HEp-2 cell-adherent E. coli, enterohemorrhagic E. coli, enteropathogenic E. coli and enterotoxigenic E. coli) were associated with endemic pediatric diarrhea in the US.

Acute Disease↗