Treatment of postmenopausal osteoporosis with continuous daily oral alendronate in comparison with either placebo or intranasal salmon calcitonin

Alendronate sodium (ALN) is a potent amino bisphosphonate which specifically inhibits osteoclastic bone resorption and has been found to reverse bone loss in several animal models. To determine if daily oral ALN treatment could prevent or reverse bone loss in osteoporotic postmenopausal women, and to compare ALN to intranasal salmon calcitonin (CT), a 2-year, double-masked, randomized, placebo-controlled study was initiated at 9 clinical centers in Italy. Two hundred and eighty six postmenopausal women (age 48-76) with spinal bone mineral density (BMD) > or = 2 SD below adult mean peak, with or without vertebral crush fractures, were randomized to one of four treatment arms: ALN 10 mg daily, ALN 20 mg daily or matching placebo (these groups all double-masked), or CT 100 IU daily (open label) for 2 years. All patients received supplemental calcium (as carbonate) 500 mg daily. Bone mass was measured by dual-energy X-ray absorptiometry of the PA lumbar spine (LS) and proximal femur (femoral neck and trochanter) at 6-month intervals. Subject safety was measured through sequential clinical and laboratory evaluation. A planned 1-year interim analysis of this ongoing study was performed centrally in a manner that maintains the double-mask for all subjects receiving oral study drug. Relative to PBO, ALN at either 10 mg or 20 mg daily increased LS BMD by 4.7% and 6.1%, respectively; each increased femoral neck BMD by 3.1% and increased trochanter BMD by 3.3% and 3.8% respectively. In contrast, CT failed to significantly increase BMD of either the spine, femoral neck or trochanter, either relative to baseline or to PBO.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of oxatomide given percutaneously to healthy volunteers

The percutaneous absorption of oxatomide gel at 5 per cent concentration was studied after single and repeated administration (85 mg b.i.d.) in six male and six female healthy volunteers, aged 25.7 +/- 0.8 years (mean +/- SEM) weighing 64.4 +/- 4.5 kg and the results compared with those obtained following a single oral dose (30 mg). The measurement of oxatomide was by means of a new sensitive and specific HPLC assay with limits of detection of 0.2 ng ml-1 in plasma and 1.0 ng ml-1 in urine. Poor percutaneous absorption was confirmed by the peak plasma concentrations which were 5.03 +/- 0.79 ng ml-1 following application of the gel for 7 days and 10.08 +/- 1.29 ng ml-1 following oral administration; the corresponding amounts of unchanged oxatomide recovered from 24 h urine collections were 1.42 +/- 0.39 micrograms and 3.93 +/- 0.92 micrograms.

[Wernicke-Korsakoff syndrome caused by prolonged infusion therapy during the postoperative period]

Wernicke-Korsakoff's syndrome (W.K.S.) is a complication of alcoholism and malnutrition and usually presents acutely and is characterized by disturbances of consciousness, paralysis of the external ocular muscles, ataxia and disorder of retentive memory. The disease results from deficiency of vitamin B1, or thiamine, an essential coenzyme in intermediate carbohydrate metabolism. We report a seriously ill, nonalcoholic surgical patient, who developed W.K.S. in the postoperative period as a result of thiamine deficiency, during prolonged intravenous therapy. It is recommended that malnourished patients receive 100 mg parenteral thiamine especially when glucose infusions are administered.

O6-methylguanine inhibits the binding of transcription factors to DNA

To study the effect of methylation of O6-guanine on the binding of cellular factors to different DNA sequences, modified oligonucleotides were constructed, in which O6-Methylguanine (O6-MeG) replaced some guanines. The DNA sequences utilized were: the region of the c-fos promoter containing the binding site for serum response factor (SRF); the region of the HIV LTR containing two binding sites for the transcription factor NF kappa B; the region of the HIV LTR containing three binding sites for the cellular factor sp1. After incubation of labeled oligonucleotides, either unmodified or containing O6-MeG, with nuclear extracts obtained from different cell lines, gel retardation assays indicated that the presence of O6-MeG resulted in inhibition of binding of cellular factors to DNA sequences located in the promoter regions of genes. This inhibition was not the same for all modified oligonucleotides but dependent on the position in which O6-MeG was located. The results obtained indicate that alkylation of O6-guanine affects the binding of transcription factors and thereby possibly the regulation of genes expression.

In vitro and ex vivo effects of recent and new macrolide antibiotics on chemotaxis of human polymorphonuclear leukocytes

The effects of five macrolide antibiotics: erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin, on human polymorphonuclear leukocyte (PMN) chemotaxis was studied in vitro and ex vivo. At therapeutic concentrations none of the antibiotics tested affected in vitro PMN chemotaxis. In vitro, erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin decreased PMN chemotaxis significantly only at the concentration of 10 mg/l, which is not usually reached in vivo. Ex vivo studies after the ingestion of therapeutic doses of erythromycin, josamycin, miokamycin and roxithromycin by five volunteers showed a significant effect on PMN chemotaxis. However, further studies are needed to confirm and better evaluate the clinical significance of recent and novel macrolides on PMN chemotaxis.

Cis dichlorodiammine platinum induced DNA interstrand cross-links in primary cultures of human ovarian cancer

We quantified and examined the kinetics of DNA interstrand cross links (DNA-ISC) caused by Cis dichlorodiammine platinum (DDP) using the method of alkaline elution in 58 highly purified human ovarian tumours growing in primary culture. A large heterogeneity in both the quantity and kinetics of DDP induced DNA-ISC was observed in cultures derived from neoplasms of different patients and from different lesions of the same patient. In the majority of cases. DNA-ISC lasted for prolonged time intervals after 1 h drug exposure, being significantly repaired only 48 or 72 h following drug washout. The persistence of DNA-ISC is probably due to a prolonged formation of these lesions for up to 24 h as assessed by the change in the repair kinetics that occurred after preventing new DNA-ISC formation by quenching of monoadducts with thiourea. The inefficient repair of DDP monoadducts appears therefore to be a possible reason for the permanence of DNA-ISC. These studies suggest that the long permanence of DNA-ISC in human ovarian cancer could be the basis for the high selectivity of DDP for this human malignancy.

Pharmacokinetics of rokitamycin after single administration to healthy volunteers

The pharmacokinetics of rokitamycin tablets were studied in 12 healthy volunteers in a randomized cross-over design. The doses tested were 200 mg, 300 mg, 400 mg and 600 mg, as single oral administration. Rokitamycin was absorbed quickly with Tmax for all doses around 30 min after drug intake. Total AUC and Cmax values were linearly related to the administered dose. The buffer formulation determined a low interindividual variation. The overall findings show a good similarity with the data obtained in Japanese subjects. Tolerability was very good.

Bioavailability of intranasal neostigmine: comparison with intravenous route

The pharmacokinetics of intranasal (i.n.) neostigmine was compared with the intravenous (i.v.) route in 6 healthy volunteers with a mean age of 25.5 years and a mean weight of 65.8 kg in a crossover design. The doses used were 0.5 mg i.v. and 21.6 mg i.n. Neostigmine was determined by HPLC. The plasmatic profiles of the two routes were similar. An early peak of plasmatic concentration after i.n. administration was observed. The absolute bioequivalence of the i.n. route was ten-fold greater than the oral one.

Selective DNA interaction of the novel distamycin derivative FCE 24517

N-Deformyl-N-(4-N-N,N-bis(2-chloroethylamino)benzoyl)distamy cin A (FCE 24517) is a novel cytotoxic and antitumor agent shortly to be investigated in phase I clinical trials. It was equally effective in inhibiting the growth of the murine L1210 line and of a subline (L1210/PAM) resistant to nitrogen mustards, whereas distamycin A was virtually inactive. The cellular uptake and retention of FCE 24517 and distamycin A were similar, thus excluding the possibility that this marked variation in cytotoxic activity was due to different intracellular concentrations of the two compounds. FCE 24517 did not appear to act as an inhibitor of macromolecule synthesis. As shown by radioactively labeled precursor incorporation only 24 h after drug treatment a significant inhibition of DNA synthesis was observed in L1210 or in L1210/PAM, when a marked proportion of cells was arrested in premitotic phase. FCE 24517 did not cause DNA breaks, DNA interstrand cross-links, or DNA-protein cross-links in L1210 cells exposed to active drug concentrations. A very low amount of radioactivity was found to be bound irreversibly to DNA in L1210 cells exposed for 1 h to [14C]FCE 24517. Using plasmid pBr322 DNA fragments in a modified version of the Maxam and Gilbert DNA sequencing technique we found no detectable binding of FCE 24517 to N-7-guanine (the major site of alkylation for classical alkylating agents), whereas some alkylations to adenine (presumably to N-3-adenine) were demonstrated. Thus it appears that FCE 24517 is a novel antitumor agent with a mode of action different from that of the drugs currently used in the clinic. In summary it is suggested that FCE 24517 acts by causing a few selective alkylations to adenines in the minor groove of DNA, although the precise base sequence necessary has yet to be elucidated.

A seasonal pattern in the onset of polymyalgia rheumatica

The seasonal distribution in the onset of polymyalgia rheumatica (PMR) was determined in 58 patients with the disease and compared with that in 44 patients affected by rheumatoid arthritis of elderly onset (EORA). Thirty six (62%) cases of PMR developed during May to August; by contrast, only 14 (31%) cases of EORA developed in the same months, this latter disease failing to show any seasonal clustering. The monthly distribution of PMR correlated with outside temperature and hours of sunshine. These data suggest that PMR might be triggered by such factors as actinic damage of superficial vessels or infective agents with a seasonal cycle. Finally, the summer clustering of PMR may be helpful in the differential diagnosis from EORA.

[Monoclonal gammopathy of uncertain significance in rheumatic disease]

Among 358 patients with rheumatic diseases, the incidence of monoclonal gammopathy of undetermined significance (MGUS) as detected by immunofixation was 4.4% (11 of 248 patients) in rheumatoid arthritis (RA), 3% (1 of 32 patients) in systemic lupus erythematosus (SLE), 6% (3 of 49 patients) in Sjögren's syndrome (SS) and 3% (1 of 29 patients) in progressive systemic sclerosis (PSS). Solid tumor was present in 4 (36%) of the 11 RA-MGUS patients. In these cases the monoclonal component could be related to a paraneoplastic syndrome rather than to rheumatic diseases. The association of rheumatic diseases, MGUS, solid tumor and immunological disorders are discussed.

[Cutaneous side effects induced by D-penicillamine in the treatment of rheumatoid arthritis]

After considering the cutaneous side effects of D-penicillamine in rheumatoid arthritis management, a few cases of cutaneous adverse reaction observed in 5 (13%) of 38 patients, who received the drugs, are described. Two patients had an early rash; one showed a late rash; one had a late rash with symptoms of initial pemphigus and drug-induced LES (presence of antinuclear and anti-dsDNA antibodies). Finally, one patient showed a drug-induced pemphigus with high titre of reticular anti-skin antibodies. All these manifestations required definitive discontinuance of the drug.

DNA damage and sequence specificity of DNA binding of the new anti-cancer agent 1,4-bis(2'-chloroethyl)-1,4-diazabicyclo-[2.2.1] heptane dimaleate (Dabis maleate)

The DNA damage and the sequence specificity of guanine-N7 alkylation produced by the novel, positively charged, antineoplastic agent 1,4-bis(2'-chloroethyl)-1,4-diazabicyclo-[2.2.1] heptane dimaleate (Dabis maleate) and its uncharged tertiary amine analogue 1,4-bis(2'-chloroethyl)-1,4-diazacyclohexane (Dabis analogue) were investigated in L1210 cells and isolated DNA. Both compounds are cytotoxic in vitro causing an arrest of L1210 cells in G2/M phase of the cell cycle. In isolated DNA, Dabis maleate alkylates guanine at the N7-position with some differences in specificity compared to other alkylating agents (e.g. nitrogen mustard). Significant differences are also evident between Dabis maleate and Dabis analogue, suggesting that Dabis analogue is not the sole alkylating species of Dabis maleate. Using the alkaline elution technique a moderate number of DNA interstrand cross-links were detected in L1210 cells treated with both compounds, which were completely repaired within 24 h. Dabis maleate and Dabis analogue do not cause DNA single strand breaks or DNA protein cross-links at the doses at which DNA interstrand cross-links were detected.

[Study of intestinal absorption of calcium using 47Ca and whole body counter in renal calculosis with hypercalciuria]

Intestinal calcium absorption was studied using orally administered 47Ca and whole body counting. Using this method, we examined 82 patients suffering from recurrent calcium urolithiasis associated with idiopathic hypercalciuria, to evaluate the incidence of elevated intestinal absorption of this ion. An oral dose of 111 kBq (3 microCi) of 47Ca chloride, together with 250 mg of stable calcium as carrier, was given to each patient. Two hours and one week later, the total body radioactivity of each subject was measured. The retention of 47Ca, as percentage of the administered dose, was then calculated. The measurements were performed with a whole body counter consisting of a two-crystal moving system with shadow shield. Forty age-matched healthy volunteers were also examined. The whole body retention of 47Ca resulted significantly higher (p less than 0.0002) in the group of patients than in the control sample, whose m +/- SD was 22.0 +/- 6.0%. In particular, by defining the normality range as 10-34% (m +/- 2SD of control results), enhanced intestinal absorption of calcium was found in 28% of the examined patients. The use of this simple examination seems to be helpful in the physiopathologic assessment of subjects suffering from calcium urolithiasis and idiopathic hypercalciuria and consequently, in their appropriate management.

[Agranulocytosis caused by dipyrone. Case reports]

Two cases of dipyrone-induced agranulocytosis are described. In the first one, the disease was due to a single administration, in the second one, to prolonged therapy. The possible pathogenic mechanism is discussed, which can be immunologic and/or toxic. The effectiveness of some of the drugs and general supportive measures applied is discussed. Health education of the patient, in conjunction with careful attention by the physician, may play an important role in the prevention of this pathological condition.

Intestinal calcium absorption in rheumatoid arthritis. A study using whole body counting

Conflicting results are reported in the literature concerning the changes in intestinal calcium absorption in rheumatoid arthritis (RA). In the present work, intestinal calcium absorption was studied in 27 postmenopausal women with RA, using whole body counting as the study method and orally administered Ca-47 as the tracer. Nobody was on corticosteroid therapy, but all received non-steroidal anti-inflammatory drugs and hydroxy chloroquine or gold compounds. The mean calcium absorption was 22.3% of the dose administered, with a standard deviation of 8.0%. The results obtained were not significantly different from those of 40 age- and sex-matched controls (mean +/- SD: 22.0% +/- 6.0%). Our findings seem to exclude the hypothesis of calcium malabsorption as one of the causes leading to osteoporosis in RA.

Duration of immunity to hepatitis B vaccination in institutionalized mentally retarded patients

Susceptible individuals of an institution for the mentally retarded (20 residents and six staff members) were vaccinated with Hevac B Pasteur (5 micrograms, months 0, 1, 2, 14). There were protective levels of anti-HBs in 75% of residents and 100% of staff members after 15 months from the first dose of the vaccine. After a 4-year follow-up period, there were persistent and protective levels of anti-HBs in 80% of residents, compared with 66% in staff members. In addition, no clinical hepatitis B infections were observed during this period.

Distamycins inhibit the binding of OTF-1 and NFE-1 transfactors to their conserved DNA elements

We investigated the effects of the antiviral agent distamycin A and of a distamycin derivative (FCE 24517) which possesses antineoplastic activity on the binding of some regulatory proteins to DNA. Both compounds inhibited the binding to DNA of the ubiquitous octamer binding factor OTF 1 and of the erythroid specific GATAAG protein (NFE 1). This was shown using the electrophoretic mobility shift assay on a DNA fragment of human gamma-globin gene promoter (-156 to -201), on the same fragment with a point mutation (T to C mutation) known to have an increased affinity of binding for NFE 1, on a DNA fragment of human histone H2B promoter and on a DNA fragment of mouse alpha 1 globin promoter. The ability of distamycin or of FCE 24517 to inhibit the binding was specific for AT-rich sequences since neither drug inhibited the binding of nuclear protein factors to the sequence CCACACCC of the human beta globin gene. Binding to DNA was investigated by evaluating the drugs' ability to protect selected sequences from DNase I digestion (DNase footprinting). Distamycins binding was highly preferential for DNA sequences containing stretches of AT. These studies indicate that chemicals which have a high degree of DNA sequence-specific binding can selectively inhibit the binding of regulatory proteins to DNA. These effects might be responsible for modification of the transcription of specific genes and might to some extent account for these drugs' antiviral and antineoplastic activities. This approach offers potential for the investigation of new such drugs.

Intracellular doxorubicin concentrations and drug-induced DNA damage in a human colon adenocarcinoma cell line and in a drug-resistant subline

The mechanisms of resistance to doxorubicin (DX) were investigated using a human colon adenocarcinoma cell line (LoVo) and a subline approximately 30 times less sensitive to doxorubicin. LoVo and LoVo/DX were similar in terms of DNA and protein content, cell volume, duration of S phase and the generation time, and proportion of cycling cells. LoVo/DX showed cross-resistance to other anthracyclines, to vinca alkaloids, epipodophyllotoxin derivatives, 4'-(9-acridinylamino-methanesulfon-m-aniside) and actinomycin D. LoVo/DX was equally sensitive to melphalan and showed collateral sensitivity to cis-platinum and 1-beta-D-arabinofuranosylcytosine. On exposing LoVo and LoVo/DX to 1.25 and 40 micrograms/ml DX respectively, for 4 hr, similar DX intracellular concentrations were reached in the two cell lines. In these treatment conditions protein associated DNA-single strand breaks or DNA-double strand breaks, assessed by alkaline elution methods were only slightly less in LoVo/DX than in LoVo cells. In LoVo/DX cells, however, DNA breaks disappeared very quickly after drug removal whereas they persisted longer in LoVo cells. This persistance is probably related to the much slower DX efflux from LoVo than LoVo/DX. When verapamil was combined with DX it inhibited the rapid DX efflux from LoVo/DX and reversed the resistance in this cell line, but it had no significant activity on LoVo cells. Verapamil also increased DX-induced DNA-single strand breaks and DNA-double strand breaks in LoVo/DX cells, but not in LoVo cells.

Hepatobiliary metabolism and urinary excretion of 4-demethoxydaunorubicin as compared to daunorubicin in rats

The hepatic metabolism and biliary excretion of 4-demethoxydaunorubicin (4DDM) was studied in Crl: CD(SD) BR rats by the liver perfusion technique. In the same strains of rats urinary excretion was investigated in vivo. Daunorubicin (DM) was always included for comparison. The drugs and their metabolites were determined in the perfusion medium, in the bile and liver and in the urine by high-performance liquid chromatography with fluorimetric detection. Compared to its analogue DM, 4DDM markedly differed in the metabolic and excretory profile. The cumulative biliary and urinary excretion of 4DDM and the metabolites was quantitatively lower than that of DM (18% vs 36% of the dose) and was consistent with prolonged persistence of 4DDM in plasma in vivo. The extensive carbonyl reduction of 4DDM and DM observed in previous in vivo pharmacokinetic studies was also evident in this study. 13-hydroxy metabolites, daunorubicinol (DMol) and 4-demethoxydaunorubicinol (4DDMol), either as such or after glycosidic cleavage, i.e. 4DDMol aglycone, were present in appreciable amounts in the perfusion medium, bile, liver and urine. In the hepatobiliary system, however, the 13-hydroxy derivative of DM amounted to a much lower fraction than the DM aglycone (17% vs 50% of the total dose), 80% of the total 4DDM dose was accounted for by 4DDMol aglycone. In urine uncleaved DMol or 4DDMol represented more than 75% of the total amount excreted for both drugs. Conjugation, a major step in the excretion of aglycones, seems to play a minor role in the biliary and urinary excretion of 4DDM and 4DDMol.

Human ovarian tumors in primary culture: growth, characterization and initial evaluation of the response to cis platinum treatment in vitro

A novel cell culture system is reported for the growth of ovarian tumors. Two approaches were developed to isolate tumor cells, one for ovarian carcinomas and the other for benign cystomas or borderline cystadenomas, which yield virtually pure tumor-cell clusters. The plating efficiency exceeded 10% in approximately 80% of the processed surgical specimens. Cells grown in a newly developed KOV medium (a modification of MCDB 151 supplemented with 6 defined growth factors and a moderate amount of FBS) had an average growth rate of 0.23 population doublings/day. Primary tumor-derived cultures, including those derived from cystomas, were analyzed by flow cytometry demonstrating a DNA heteroploid content in 55% of the cases. The neoplastic origin of the cells in culture was further confirmed by 3 monoclonal antibodies (OC125; MOv2; MOv19) with high specificity against epithelial ovarian malignancies. Cultures were tested with cis-DDP to determine their suitability for pharmacological studies. Exposure to the drug (from 10 to 80 microM for 1 hr) resulted in variable cell-killing responses, and the prominent effect on cell-cycle progression in primary cultures was a prolonged arrest in S phase. The formation and persistence of DNA-ISC caused by an exposure to 40 microM cis-DDP for 1 hr was studied by alkaline elution in 6 different tumor-derived cultures. DNA-ISC equivalents were highest between 9 and 24 hr after treatment and were repaired only to a limited extent within 48 hr of recovery time. The present study confirms the usefulness of this culture system for pharmacological studies of active chemotherapeutic agents against human ovarian tumors.

Accumulation of DNA strand breaks in cells exposed to methotrexate or N10-propargyl-5,8-dideazafolic acid

N10-Propargyl-5,8-dideazafolic acid (CB 3717), a new antifolate which directly inhibits thymidylate synthase and which is now under early clinical investigation, was compared with methotrexate (MTX) for its antiproliferative activity and mode of action on M14 human melanoma cell line and NIH/3T3 murine fibroblasts transfected with human c-Ha-ras oncogene (NIH/3T3R). CB 3717 was as active as MTX on both cell lines in inhibiting colony formation, but 20-100 times less potent. After 24 h of exposure both drugs caused an accumulation of cells in the G1 phase of the cell cycle, probably because of inhibition of DNA synthesis and blockage at the G1-S boundary. In NIH/3T3R treated for 16 h with 2 microM MTX or 200 microM CB 3717, we found DNA single-strand breaks amounting to approximately 130 and 140 rad equivalents, respectively, and a considerable number of DNA double-strand breaks, far more than expected if they had been the result of the proximity of single-strand breaks on the two complementary DNA strands. No DNA-protein cross-links were detected. When cells were incubated in drug-free medium for 8 h, there was a further accumulation of single-strand breaks, possibly due to the effects of the drug retained intracellularly as polyglutamyl derivative. Simultaneous treatment with 1.77 microM cycloheximide prevented DNA damage produced by both drugs. Thymidine (10 microM), renewed in the culture medium every 24 h, also prevented DNA damage and cytotoxicity. Since after 16 h treatment with MTX or CB 3717 cells were completely viable, as assessed by [3H]thymidine release, trypan blue exclusion test, and 51Cr release, DNA damage appears to be an early event preceding cell death and may be a feature of the killing ability of the drugs. The involvement of a protein in the formation of DNA breaks is suggested by the fact that when protein synthesis was inhibited with cycloheximide DNA damage was no longer seen.

Temporal arteritis in seropositive rheumatoid arthritis with rheumatoid nodule

A 61-year-old woman, suffering from classic seropositive rheumatoid arthritis with rheumatoid nodule histologically documented, developed temporal arteritis. HLA-DR typing revealed the presence of DR3 and DR4 antigens. The findings from previous studies support the association of HLA-DR antigens, giant cell arteritis-polymyalgia rheumatica and rheumatoid arthritis, and suggest the participation of a common immunogenetic mechanism in their pathogenesis.

The diffusion of pirprofen into the cerebrospinal fluid in man

We have measured the concentrations of pirprofen at various times in plasma and cerebrospinal fluid (CSF) samples, drawn during diagnostic myelography from 28 patients affected by sciatica. After intramuscular injection of 400 mg plasma concentrations of pirprofen reached a peak in 60 min then fell slowly. In contrast, the CSF concentration rose until 12 h and then fell. Pirprofen rapidly crossed the blood-brain barrier and was detectable in CSF at 15-30 min after injection. These results support the suggested hypothesis of a central analgesic action of pirprofen along with the known peripheral one. A new sensitive HPLC method was developed for measuring the concentration of pirprofen in the CSF.

DNA damage, cytotoxic effect and cell-cycle perturbation of Hoechst 33342 on L1210 cells in vitro

This study was designed to evaluate the effects of vital dye Hoechst 33342 (HO 33342), at concentrations used to obtain a good DNA histogram resolution, on DNA integrity, cell growth, and cell-cycle phase distribution of L1210 cells. HO 33342 exposure for 2 h, at 37 degrees C produced DNA single-strand breaks as assessed by the method of alkaline elution. DNA single-strand breaks were concentration dependent (in the range .5-5 micrograms/ml) and increased significantly when HO 33342 (0.5-1.5 micrograms/ml) was associated with exposure in a flow cytometer to U.V. laser beam illumination. HO 33342 produced a cytotoxic effect on cell growth even at the concentration of 0.5 microgram/ml--a concentration ten-fold smaller than those required to obtain a good DNA histogram resolution. HO 33342 produced a severe block of the cells in the G2-M phase of the cell cycle already evident 24 h after stain exposure and continuing up to 144 h after start of recovery. A new polyploid cell population (with a 4 c DNA content) not present in the unstained cells was already evident 24 h after dye exposure. The data shown in the present paper would imply caution in using sorted cells stained with HO 33342 dye for biological, biomedical, and pharmacological studies.

In vitro and in vivo methazolastone-induced DNA damage and repair in L-1210 leukemia sensitive and resistant to chloroethylnitrosoureas

DNA damage caused by methazolastone [an analogue of 5-(3,3-dimethyl-1-triazeno)imidazole-4-carboxamide which does not require metabolic activation] was investigated in L-1210 leukemia which is sensitive to this drug and in a L-1210 subline [L-1210/N,N-bis(2-chloroethyl)-N-nitrosourea (BCNU)] which is resistant to both chloroethylnitrosoureas and methyltriazenes. Both in vitro and in vivo metazolastone caused formation of DNA alkali-labile sites (assessed by alkaline elution techniques) which were present in similar amounts and repaired at a similar rate in L-1210 and L-1210/BCNU. This suggests that these lesions are not crucial to methyltriazenes activity. DNA alkali-labile sites may be due to the removal of 7-methylguanine by 7-methylguanine-DNA glycosylase which showed the same activity in L-1210 and L-1210/BCNU. Flow cytometry studies revealed that in L-1210 but not in L-1210/BCNU methazolastone induced an arrest of cells in SL-G2-M phases. This blockade was delayed, occurring after at least two cell divisions after drug treatment and therefore appeared temporally unrelated to the presence of DNA alkali-labile sites. There was three times more O6-methylguanine-DNA methyltransferase in L-1210/BCNU than in L-1210 suggesting that methylation of O6-guanine is an important lesion for methyltriazenes activity and resistance to this drug may be linked to its repair.

Prostaglandin and thromboxane synthesis by M5076 ovarian reticulosarcoma during growth: effects of a thromboxane synthetase inhibitor

The five stable metabolites [prostaglandin F2 alpha (PGF2 alpha), prostaglandin D2 (PGD2), prostaglandin E2 (PGE2), thromboxane B2 (TXB2), and 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha)] of arachidonic acid (AA) via the cyclooxygenase pathway were measured by high-resolution gas chromatography-mass spectrometry in M5076 ovarian reticulosarcoma (M5) homogenates at various times after tumor implantation (Days 15, 18, 21, and 24). Vegetating tumor showed an active AA overall metabolism, which significantly increased during tumor growth. Synthesis of selected products (TXB2, PGD2, and PGE2) increased markedly over time (up to 10.6, 3.5, and 0.9 micrograms/g, respectively). The overall metabolic profile was TXB2 much greater than PGD2 greater than PGF2 alpha greater than 6-keto-PGF1 alpha greater than PGE2 on Day 15 and TXB2 much greater than PGD2 much greater than PGF2 alpha greater than 6-keto-PGF1 alpha on Day 24. TXB2 was also by far the most abundant product of in vitro-cultured M5 cells. Chronic treatment of M5-bearing mice with dazmegrel (UK-38,485), a selective thromboxane synthetase inhibitor (100 mg/kg p.o. daily, from Day 7 to killing), resulted in incomplete TXB2 synthesis inhibition, AA metabolism diversion toward the other prostaglandins, and no effects of tumor growth and metastasis. More frequent dazmegrel treatment (100 mg/kg p.o. every 8 h from Day 1 to killing) resulted in complete TXB2 synthetase inhibition, AA metabolism diversion, and increased tumor growth and metastasis. These data do not support the hypothesis of thromboxane synthetase inhibitors reducing tumor growth. However, since TXB2 suppression was accompanied by the production of other products possibly interfering in tumor growth, no conclusions on the effective role of TXA2 in malignancy can be drawn.

Tubulo-interstitial lesions mediate renal damage in adriamycin glomerulopathy

The present study was designed to investigate the relationship between proteinuria, focal sclerosis, and tubulo-interstitial changes in the evolution of renal damage in experimental nephrosis. We utilized an accelerated unilateral model of adriamycin (ADR) nephrosis characterized by morphological changes more severe than in the classical model. The first events in ADR-induced glomerulopathy were epithelial cell damage and proteinuria. Subsequently, tubular casts were formed at the distal level. The cast formation preceded the development of interstitial damage, which was determined by tubular obstruction and breaking of tubular basement membrane (TBM), which in turn promoted an interstitial inflammatory reaction. Despite the severity of tubulo-interstitial damage observed after a long period of heavy proteinuria, the incidence of focal segmental glomerulosclerosis (FSG) was very low. The results of the present study indicate that chronic proteinuria is not necessarily accompanied by the development of focal sclerosis. Tubulo-interstitial lesions appear to be the most important determinant for the progression of renal damage in this model.

[Sarcoidosis of oculo-parotid onset. Differential diagnostic considerations]

Two cases of sarcoidosis, presenting with parotid gland enlargement and keratoconjunctivitis sicca, are here described. The difficulty encountered in making correct diagnosis is then stressed. The diagnostic value of invasive and non invasive techniques in the study of parotid gland pathology and function in sarcoidosis is then reviewed.

Comparative metabolism of daunorubicin and 4-demethoxydaunorubicin in mice and rabbits

In the present study, the biodisposition of 4-demethoxydaunorubicin (4DDM) and its 13-dihydrometabolite was compared with daunorubicin (DM) and its metabolite in rabbit serum, and the results were considered in the light of this DM analog's pharmacokinetic behavior in mice. In rabbit serum, the levels of the 13-OH derivative of both DM and 4DDM (daunorubicinol and 4-demethoxydaunorubicinol) were higher than in mice. In vitro metabolic studies with mouse and rabbit cytosol indicated that the hepatic metabolism was quantitatively important for both analogs (70%-90% for DM and 4DDM was reduced to the 13-OH metabolite), but the rabbit had a much higher specific capacity to metabolize these compounds. DM seemed a better substrate for cytoplasmic aldoketoreductase, the enzyme affinity in rabbits being three times higher than for 4DDM. Cytotoxicity studies in vitro showed that 4-demethoxydaunorubicinol, unlike daunorubicinol, was as cytotoxic as the parent compound, and this suggests this metabolic step does not inactivate 4DDM but contributes to its high and long-lasting biological activity in vivo.

In vivo studies with the novel anticancer agent mitozolomide (NSC 353451) on Lewis lung carcinoma

Mitozolomide is one of the most effective drugs against Lewis lung carcinoma in the mouse. Two IP doses of 40 mg/kg (days 6 and 15 after IM transplantation of 3LL) or four doses of 20 mg/kg given at various intervals (starting from day 6) increased survival time by 100%. A single IP dose of 80 mg/kg was toxic, and 10 mg/kg was ineffective even when this dose was given on eight occasions. The pharmacokinetics of mitozolomide was investigated in 3LL-bearing mice by HPLC assay. Peak drug levels were achieved in tumor 15 min after IP treatment, after which they declined according to first-order kinetics, with a half-life of 80-100 min (the same as in plasma). No dose-dependent kinetics was observed. Flow cytometry studies showed an accumulation of 3LL cells in G2M 24 h after drug treatment. This cell cycle perturbation was reversed 96 h after the inactive dose of 10 mg/kg, but not after the effective dose of 40 mg/kg.

Comparison between VP 16 and VM 26 in Lewis lung carcinoma of the mouse

The antitumoral activity and pharmacokinetics of VP 16 and VM 26 were comparatively investigated in Lewis lung carcinoma (3LL)-bearing mice. When the two drugs were given at equitoxic doses, in single or repeated treatment, the superior antitumoral activity of VM 26 was clear. Compared to VP 16, VM 26 had a different pattern of distribution, with a larger volume of distribution, a longer elimination half-life time and a lower clearance. The tissue to plasma AUC ratios indicated that VM 26 concentrated more in tumor and heart while VP 16 gave highest concentrations in liver and intestine. Flow cytometry studies showed that VM 26 was more potent than VP 16 in causing cell cycle perturbation of 3LL cells growing in primary culture. VM 26 displayed cytotoxic activity at a concentration in the medium one-tenth that of VP 16. The uptake of VM 26 by 3LL cells was 15 times that of VP 16.

Horseradish peroxidase/hydrogen peroxide-catalyzed oxidation of VP16-213. Identification of a new metabolite

VP16 was submitted to oxidation catalyzed by horseradish peroxidase (HRP) and H2O2 in phosphate buffer (pH 7.0). The product of the reaction, which has a high performance liquid chromatographic (HPLC) retention time different from the previously known metabolites of VP16, was identified as 1,2,3,4-tetradehydro-VP16 by 1H-NMR and mass spectrometry (MS) analysis. It was found to result from the loss of four hydrogens and the formation of an aromatic ring (ring C of VP16). This new product retains, in the 4' position of the E ring of VP16, the hydroxy group which is crucial for the antitumoral activity of podophyllotoxin derivatives. The reaction was linear in a wide range of VP16 concentrations and was dependent on the concomitant presence of peroxidase and H2O2.

Prostaglandin and thromboxane synthesis by Lewis lung carcinoma during growth

The five stable metabolites [prostaglandin F2 alpha, prostaglandin D2, prostaglandin E2 (PGE2), thromboxane B2, and 6-keto-prostaglandin F1 alpha] of arachidonic acid (AA) via the cyclooxygenase pathway were measured by high-resolution gas chromatography-mass spectrometry in Lewis lung carcinoma homogenates at various times after tumor implantation (11 to 25 days). Vegetating and necrotic sections of the primary tumor and lung metastases were examined. Vegetating tumor showed a very active AA metabolism. Synthesis of PGE2, the most abundant product, markedly increased during tumor growth (up to 30 micrograms/g). A high and increasing synthetic capacity was also noted for prostaglandin D2 (up to 9 micrograms/g). Minor time differences and lower levels (up to 1.4 micrograms/g) were found for the other AA metabolites. PGE2 and prostaglandin D2 were the major products in necrotic tumor, too, but synthesis was markedly less than in vegetating tumor, and no increase was noted over time. Metastatic tissue showed a different AA metabolic profile, as compared to primary tumor and surrounding lung tissue, with PGE2 and 6-keto-prostaglandin F1 alpha being the main metabolites.

Low-protein diet prevents glomerular damage in adriamycin-treated rats

Adriamycin (ADR) induces glomerular damage in rats with persistent proteinuria which develops 13 to 15 days after a single intravenous (i.v.) injection (5 mg/kg). Electron microscopy (EM) shows alterations of glomerular visceral epithelial cells with foot process fusions. The disease resembles minimal change nephropathy in humans. We studied the effect of two isocaloric diets with different protein content on urinary protein excretion, renal function, and glomerular morphology in rats treated with ADR. Six groups of rats were used. Group 1 received a single i.v. injection of ADR and was fed a standard diet containing 20% protein. Group 2 was fed a low-protein diet containing 6% protein starting 7 days before ADR. Group 3 was fed a low-protein diet starting the day after ADR. Group 4 served as control. Two additional groups of rats (5 and 6) were used to study the kidney distribution of ADR. Unlike animals fed the standard diet, animals fed the low-protein diet did not develop proteinuria. The kidney distribution of ADR measured at different intervals after drug injection was not influenced by the diet. Renal function as determined by glomerular filtration rate (GFR) and renal plasma flow (RPF) was not significantly modified in nephrotic rats receiving the standard diet compared to control animals. The low-protein regimen induced a significant elevation in RPF compared to the standard diet, but had no influence on GFR. Light and transmission EM studies showed alterations of glomerular visceral epithelial cells with fusion of foot processes in rats fed the standard diet, whereas no significant abnormalities of glomerular epithelial cells were detectable in animals receiving the low-protein diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Central side effects of pentamethylmelamine: biochemical and behavioural studies

The central side effects of pentamethylmelamine (PMM), an antitumoral agent, were studied on brain neurotransmitters from the biochemical and behavioural points of view. PMM causes a dose-related reduction in the body temperature and motility of mice. 100 mg/kg of PMM lowers the levels of noradrenaline (NA) and raises 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) in the telencephalon. A similar dose increased striatal levels of dopamine (DA) metabolites, homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC), at earlier times (30 min), reducing their levels at 2 hr. These effects disappear at longer times (4 hr). No changes were observed in the levels of 3-methoxytyramine (3-MT), the extraneuronal metabolite of DA. The serotonin metabolite 5-hydroxyindolacetic acid (5HIAA) was almost not affected. PMM and its metabolites do not displace [3H]-spiroperidol from mouse striatal binding sites. These data show that some of the neurological effects induced by PMM are associated with changes in the metabolism and/or release of brain catecholamines but are not mediated by direct action on DA receptors.

Abnormalities of peripheral blood T lymphocyte subsets in polymyalgia rheumatica

The T lymphocyte subsets were studied by monoclonal antibodies in the blood of eight patients with polymyalgia rheumatica. The percentages of circulating T cells (OKT3+) were lower when compared with normal controls (p less than 0.02), as were the proportions of suppressor/cytotoxic (OKT8+) T cells (p less than 0.001), whereas the proportions of helper/inducer (OKT4+) T lymphocytes were not changed. Consequently, the OKT4:OKT8 ratio was higher in patients with polymyalgia rheumatica than in controls (p less than 0.001). On the contrary, circulating B cells were not altered. The decrease in peripheral blood OKT3+ and OKT8+ lymphocyte subsets suggests that there is an impairment of cell-mediated immunity in polymyalgia rheumatica.

Biochemical studies on the ability of pentamethylmelamine to interact in vivo with DNA and proteins in a sensitive murine ovarian reticular cell sarcoma

The metabolism of 14C-PMM and its irreversible interaction with DNA and proteins were studied in M5076/73A reticular cell sarcoma, a murine solid tumor previously shown to be sensitive to the drug. Metabolism and irreversible binding were determined 0.25, 1, 8 and 104 hours after a single i.p. injection of radiolabelled PMM, tumor and liver macromolecular binding were compared with two differently 14C-labelled PMM, i.e. ring- and methyl-PMM. Ring-PMM derived macromolecular binding appeared to have more relevance in vivo and had a similar time profile in both liver and tumor. Ring-PMM derived DNA binding was then related to metabolic steps between PMM and 2,2,4,6 TMM and 2,2,4,6 TMM itself and 2,4,6 TriMM.

Activity and distribution of iv and oral 4-demethoxydaunorubicin in murine experimental tumors

The antitumor activity of 4-demethoxydaunorubicin ( 4DDM ) compared to its parent compound daunorubicin (DM) was investigated in C57BL/6 mice bearing a T-cell lymphoma, the EL-4, chosen because of its sensitivity to this compound. 4DDM was moderately effective against Lewis lung carcinoma and M5076 ovarian reticulosarcoma tumor systems. Against the EL-4 tumor, after either iv or oral treatment, 4DDM had a good therapeutic effect (survival time in treated mice was almost double that in untreated mice) which was comparable to that of iv doxorubicin. Serum and tissue distribution of 4DDM and its reduced metabolite 4- demethoxydaunorubicinol , given either iv or orally at therapeutic doses to EL-4-bearing mice, was then compared with iv DM using a high-performance liquid chromatography technique with fluorimetric detection. DM seemed to be cleared faster and to a greater extent by metabolism than 4DDM , with half-lives after iv treatment of 23 hrs for 4DDM versus 4.6 hrs for DM. The reduced metabolite in serum amounted to greater than 100% of the concentration of the native compound for DM and less than 20% for 4DDM . By both the iv and oral routes, 4DDM appeared to be concentrated and retained in tissues to a proportionally higher extent than DM, with drug exposure being at least twice as high with correspondingly longer half-lives in almost all tissues investigated, including the tumor. Moreover, this demethoxy analog appeared to be somewhat more selective than DM, since the relative capacity of the tumor tissue to accumulate this compound seemed higher than that of other organs (eg, heart and spleen) reported to be targets of toxicity. Oral administration gave more favorable distribution, resulting in the highest tumor to heart and spleen concentration ratio; this suggests a superiority of this route of administration.