Effect of dietary chlorophyll derivatives on mutagenesis and tumor cell growth.

Much attention in recent years has been given to the antigenotoxicity of chlorophyll. Chlorophyll, however, is known to be converted into pheophytin, pyropheophytin, and pheophorbide in processed vegetable food and following ingestion by humans. Studies were conducted on the antimutagenic and tumoricidal potencies of these compounds. All the chlorophyll derivatives tested exhibit identical antimutagenic effect towards 3-methylcholanthrene (3-MC), suggesting that the porphyrin nucleus may complex directly with the mutagen. It does not exclude, however, another mechanism of activity involving inactivation the enzymatic transformation of 3-MC. In contrast, the action of N'-nitro-N'-nitrosoguanidine (MNNG) depends upon structural differences between the chlorophyll derivatives. It is significantly lower when the phytol-containing pheophytin and pyropheophytin are tested as to that of the phytol-lacking pheophorbide. The higher concentrations of the chlorophyll derivatives were required to reduce the mutagenicity of MNNG than needed for 3-MC. The cytotoxicity of chlorophyll derivatives against tumor cells also was evaluated. The cellular uptake and inhibition of myeloma cell multiplicity were found to be greater for pheophorbide than for pheophytin. Calculated on the amount of cell associated chlorophyll derivative, however, pheophytin was more cytostatic/cytotoxic than pheophorbide. The results presented in this report indicate that food sources that yield chlorophyll derivatives may play a significant role in cancer prevention. Teratogenesis Carcinog. Mutagen. 19:313-322, 1999.

Antimutagenicity, cytotoxicity and composition of chlorophyllin copper complex.

The preparation of chlorophyllin copper complex (CCC), shown to be a tumor promoter in an animal model (Nelson, R.L. (1992) Chlorophyllin, an antimutagen, acts as a tumor promoter in the rat-dimethylhydrazine colon carcinogenesis model. Anticancer Res., 12, 737-740), also inhibits the activities of direct- and indirect-acting mutagens in the Salmonella assay and exhibits cytostatic and cytocidal effects toward myeloma cells. Data from elemental analyses, spectrophotometry and reversed-phase high-performance liquid chromatography indicate that CCC preparations generally used in antimutagenic/anticarcinogenic experiments are variable, complex mixtures of structurally distinct porphyrins lacking copper in some instances. This variability of the composition may be a cause for the differences reported for the tumor promotion activity of CCC.

Need and Demand for Oral Medicine Services in 1996. A report prepared by the Subcommittee on Need and Demand for Oral Medicine Services, a subcommittee of the Specialty Recognition Committee, American Academy of Oral Medicine.

The need and demand for oral medicine services in the United States and Canada was determined by a prospective survey of American Academy of Oral Medicine practitioners who attended the Academy's 1996 annual meeting. Of the 50 surveys returned from 149 eligible registrants, it was determined that, on the average, oral medicine practitioner respondents practiced 2.3 days per week and treated 8.7 patients per day; this amounts to more than 40,000 patient-care visits per year. Almost 90% of patients were treated because of medically compromising conditions, oral mucocutaneous disease, or chronic orofacial pain. Most of the care (52%) was provided in non-university settings. Most treatment involved the comprehensive evaluation of complex oral problems (36.7%), the prescription of medications (24.2%), or comprehensive dental treatment (21.8%) for patients with severe and life-threatening medical conditions. These results suggest that oral medicine services are needed and that demand for these services is high.

Automated liquid chromatographic determination of ranitidine in microliter samples of rat plasma.

An improved high-performance liquid chromatographic method with UV detection at 313 nm has been developed for quantitation of ranitidine in 100 microliter of rat plasma over the range 25 to 1000 ng/ml. To each sample were added the internal standard (metiamide) and 2 M NaOH. After dichloromethane extraction, the nitrogen-dried extracts were reconstituted in the mobile phase of 0.01 M phosphate buffer-triethylamine-methanol-water (530:5:390:75 v/v). Chromatography on mu Bondapak C18 with quantitation by peak height ratios showed an analyte recovery of 97%; a limit of detection of 10 ng/ml; a precision of 1-10% and an accuracy of 1-5%. About 90 samples can be processed in 24 h.

Oral manifestations of drug therapies in the geriatric patient.

Oral manifestations of drug therapies in the geriatric patient must be considered in a multifactorial approach. A logical pattern of individual "normality" must be perceived, and variation from this pattern, with the aid of both physical examination and adequate drug history, will enable the clinician to interpret protean manifestations of untoward actions of chemotherapeutic agents in and about the oral cavity.

Bioanalysis of cimetidine by high-performance liquid chromatography.

Cimetidine, N"-cyano-N-methyl-N'-[2[[(5-methyl-1H-imidazol-4-yl) methyl]-thio]ethyl]guanidine, is a specific histamine H2-receptor antagonist drug that is widely used in medicine to treat gastric ulcer disease and other pathological hypersecretory states. To study the bioavailability of cimetidine, it was necessary to develop a rapid and reliable high-performance liquid chromatography procedure for quantitating the drug in body fluids. In this new procedure, cimetidine is adsorbed directly from urine or plasma, without prior clean-up, on to a mini-column prepacked with C18 material (Sep-Pak C18 cartridge). Acetonitrile is used to elute the drug, and the eluate is analyzed by high-performance reversed-phase liquid chromatography on a Partisil 10 ODS column, with an aqueous phosphate-methanol mixture as the mobile phase and UV detection at 228 nm. This method for analyzing cimetidine in body fluids is rapid, accurate and precise and differs from previously reported methods in that it eliminates the need for performing bothersome single or multiple, dualphase solvent extractions. Moreover, slight modifications in the composition of the mobile phase permit the simultaneous determination of cimetidine metabolites.

Osteitis deformans. Report of a long-standing case with extensive oral involvement.

Presented is a case of osteitis deformans (Paget's disease of bone) with a 38-year history after diagnosis. The patient had nearly the entire spectrum of symptoms that can result from widespread involvement of the skeletal system with this disease. Diffuse involvement of the maxilla and mandible resulted in postextraction complications which are common in Paget's disease of the bone.

Treatment of the oral complications of leukemia.

Complicating infectious processes and manifestations of immunosuppression were either cured or symptoms were decreased with aggressive therapy in 24 patients with acute leukemia and five with chronic leukemia. Oral surgical intervention combined with histocompatability-matched transfusion therapy can safely eliminate sources of sepsis and alleviate pain in patients who have undergone immunosuppressive and myelosuppressive treatment.

Comprehensive health care clinic for hemophiliacs.

One hundred hemophiliacs were examined at a formal comprehensive health care clinic. Sixty-eight percent had abnormal results of liver function tests, and 26% had spleens that were palpable. Measurement of range of motion of knees, ankles, hips, shoulders, and elbows showed a high incidence of hemophilic arthropathy and established a precise baseline by which to judge efficacy of therapy. Results of dental examination disclosed a 14% incidence of multiple severe caries, which is an incidence lower than that of the population as a whole. Examples of inadequate dosage of replacement therapy (16%) and chronic delay in application of self-therapy (14%) were discovered. An 8% incidence of hypertension was noted; prior experience suggests that the combination of hypertension and hemophilia may be lethal. Other clinical and laboratory data also illustrate the importance of a periodic, formally structured, comprehensive examination of hemophiliacs.