Molecular mechanism of action and pharmacokinetic properties of methotrexate.

Since its discovery in 1945, methotrexate has become a standard therapy for number of diseases, including oncological, inflammatory and pulmonary ones. Major physiological interactions of methotrexate include folate pathway, adenosine, prostaglandins, leukotrienes and cytokines. Methotrexate is used in treatment of pulmonary sarcoidosis as a second line therapy and is drug of choice in patients who are not candidates for corticosteroid therapy, with recommended starting weekly dose of 5-15 mg. Number of studies dealt with methotrexate use in rheumatoid arthritis and oncological patients. Authors are conducting research on oral methotrexate use and pharmacokinetics in chronic sarcoidosis patients and have performed literature research to better understand molecular mechanisms of methotrexate action as well as high level pharmacokinetic considerations. Polyglutamation of methotrexate affects its pharmacokinetic and pharmacodynamic properties and prolongs its effect. Bile excretion plays significant role due to extensive enterohepatic recirculation, although majority of methotrexate is excreted through urine. Better understanding of its pharmacokinetic properties in sarcoidosis patients warrant optimizing therapy when corticosteroids are contraindicated in these patients.

Industrial hemp decreases intestinal motility stronger than indian hemp in mice.

BACKGROUND: Indian hemp has shown beneficial effects in various gastrointestinal conditions but it is not widely accepted due to high content of tetrahydrocannabinol resulting in unwanted psychotropic effects. AIM: Since industrial hemp rich in cannabidiol lacks psychotropic effects the aim of research was to study the effects of industrial hemp on intestinal motility. MATERIALS AND METHODS: Animals were randomly divided in six groups (each group consisting of 6 animals): Control group, Cind group - receiving indian hemp infuse for 20 days, Cids group-receiving industrial hemp infuse for 20 days, M group - treated with single dose of morphine (5 mg/kg i.m.) Cind+M group - treated with indian hemp infuse and single dose of morphine (5 mg/kg i.m.), Cids+M - treated with industrial hemp infuse and single dose of morphine (5 mg/kg i.m.). On the 20th day of the study animals were administered charcoal meal, and were sacrificed 35 minutes after administration. Intestinal motility was estimated according to distance between carbo medicinalis and cecum in centimeters. RESULTS: Decrease of intestinal motility in animals treated with indian hemp infuse was not significant compared to controls and it was smaller compared to animals treated with morphine (Indian hemp =15.43±10.5 cm, morphine = 20.14±5.87 cm). Strongest decrease of intestinal motility was recorded in animals treated with industrial hemp infuse, and it was significant compared to controls and morphine (industrial hemp = 26.5±9.90 cm, morphine = 20.14±5.87 cm; p < 0.005). CONCLUSIONS: Although not completely without psychotropic activity cannabidiol could be a potential replacement for tetrahydrocannabinol. Since industrial hemp infuse rich in cannabidiol reduces intestinal motility in healthy mice cannabidiol should be further evaluated for the treatment of intestinal hypermotility.

Pharmacodynamic action of a commercial preparation of the mushroom Coprinus comatus in rats.

The pharmacodynamic effect of a 7-day oral treatment with a suspension of Coprinus comatus at doses of 0.835 and 1.670 g/kg in rats was studied. Changes in body weight, bile secretion and hypoglycaemic action were examined together with antipyretic activity and paw oedema tests. Such treatments resulted in a significantly lower increase in the body weight of tested animals (15.73 ± 8.36 g/rat in the untreated group, 8.44 ± 8.23 g/rat (p < 0.05) and 3.18 ± 7.93 g/rat (p < 0.05), for C. comatus 0.835 and 1.67 g/kg, respectively). Hypoglycaemic action was evident only in the glucose load test (6.79 ± 0.61 to 9.70 ± 1.16 (p < 0.05) in the untreated group and 6.47 ± 0.35 to 7.27 ± 0.76 for C. comatus 1.67 g/kg). Histological examination of pancreas cross-sections suggested certain protective functions of the mushroom suspension in alloxan poisoning. In the antipyretic test, a significantly lower increase in body temperature was observed in the mushroom-pretreated rats. In the paw oedema test, no decrease in oedema induced by formalin injection was observed following treatment with C. comatus.

[Postradiation osteosarcoma in a patient with multiple myeloma]. / Postradijacioni osteosarkom kod bolesnice s multiplim mijelomom.

The described patient presents a rare combination of primary and secondary malignant bone tumours. The primary bone tumour was histologically established as myeloma, and was treated by radiation and multiple-drug chemotherapy. The secondary tumour, histologically confirmed 19 years later, was osteogenic sarcoma occuring in the radiation field when clinical and laboratory examinations showed remission of the primary lesion. The age of the patient, the localisation of the second tumour in the radiation field, the latent period of elapsed years, histologic and radiographic evidence of the pre-existent osseous lesion (myeloma), indicate that the secondary tumour (osteogenic sarcoma) can be induced by irradiation.