Expectation-maximization algorithms, null spaces, and MAP image restoration

A computationally efficient, easily implementable algorithm for MAP restoration of images degraded by blur and additive correlated Gaussian noise using Gibbs prior density functions is derived. This algorithm is valid for a variety of complete data spaces. The constraints upon the complete data space arising from the Gaussian image formation model are analyzed and a motivation is provided for the choice of the complete data, based upon the ease of computation of the resulting EM algorithms. The overlooked role of the null space of the blur operator in image restoration is introduced. An examination of this role reveals an important drawback to the use of the simulated annealing algorithm in maximizing a specific class of functionals. An alternative iterative method for computing the nullspace component of a vector is given. The ability of a simple Gibbs prior density function to enable partial recovery of the component of an image within the nullspace of the blur operator is demonstrated.

[Anatomy and clinical application of transcervicothoracic polyphyletic blood supply skin flap]

Transcervicothoracic skin flap was used to repair the faciocervical scars left after burns in 56 cases. Anatomy and clinical application proved that the transverse cervical artery branches out a constant skin artery before it enters the trapezius muscle and this artery, after crossing the clavicle, is divided into two branches, one extending outwards, and the other downwards. The internal thoracic artery branched out an intercostal perforator on the spot 1 cm to the parasternum. The perforator extended along the intercostal plane and belonged to the direct skin artery. The rate for perforation between the second and third ribs was the highest and the diameter of the perforator the greatest. The thoracoacromial skin artery perforated through the medialsemis between the greater pectoral muscle and the deltoid muscle, and extended toward the shoulder, supplying the skin of the infraclavicular, deltoid and upper greater pectoral regions with blood. Anatomy and contrast examination showed that there are extensive anastomoses between the three groups of blood vessels. On the basis of these anastomotic branches, transregional skin flaps can be designed to repair faciocervical damages. These flaps were successfully used in the 56 cases, with 32 cases having the the branch of cervical segment of the trasverse cervical artery as the pedicle, and 24, the second and third perforators of the internal thoracic artery as the pedicle. It was proved that the transregional flaps can be successfully transferred regardless of the sites of the pedicles.

[The causes of necrosis of arteriovenous flap and its modification]

Arteriovenous flaps have been developed for more than ten years, however the cause of necrosis of the flap remains obscure. We observed the changes in the microcirculation of the flap, and it was revealed that most of capillaries were occluded in the early arterialized stage, and the capillary patency was only 10%-20%. The latter was increased to 80%-90% three days later. All these changes were due to the damage of endothelial cells by arterial blood, because of high pressure and oxygen tension, resulting if cell swelling, fissuring, exfoliation and finally thrombosis. As a consequence, the effective microcirculation volume became decreased. As venous endothelial cells required time to adapt arterial blood, and expansion of skin could increase tissue capillaries in number, the arteriovenous flap was modified by skin expansion before arterialization. This method improved the survival rate remarkably.

Modulation of integrins expression during human osteoblasts "in vitro" differentiation

We here report the modulation of the adhesion of cultured human osteoblasts on Laminin during the acquisition of differentiated phenotype. We also show that interference with the differentiation program caused by treatment with Retinoic acid of the cultures, causes changes of the capability to adhere to Laminin and type I Collagen. The younger or dedifferentiated cells have lower capability to bind to Laminin or Collagen. The maturation associated changes are specific for the adhesion to the above substrata and do not involve the adhesion to FN or plastic. The alpha subunit(s) of the integrin receptor(s) for these proteins is likely to be responsible for the modulation adhesion to Laminin and Collagen.

Reducing Berreman's 4 x 4 formulation of liquid-crystal-display optics to 2 x 2 Jones vector equations

We use a perturbation expansion to obtain a generalized 2 x 2 Jones vector description that is equivalent to Berreman's description. We show that for typical liquid-crystal displays (LCD's) the bulk reflections are weak so that the first-order 2 x 2 Jones solution is generally sufficient and affords fast and reasonably accurate computations of the overall optical properties of LCD devices.

Pharmacology of intrathecal VP-16-213 in dogs

VP-16-213 is an anticancer drug that is active against a number of malignancies including small cell lung cancer, lymphoma, and leukemia which are often complicated by the development of leptomeningeal carcinomatosis. To investigate the potential usefulness of VP-16-213 for intrathecal administration, the pharmacology and toxicity of intrathecal VP-16-213 was determined. VP-16-213 at varying doses (0.01-1.0 mg.kg) was instilled intrathecally in dogs. Plasma, CSF, spinal cord, and brain tissue drug concentrations were determined by radiochemical and high performance liquid chromatography technique. Drug concentrations were strikingly higher in spinal cord tissue near the injection site compared to more distal cord sites. CSF concentration of VP-16-213 is 3-4 logs higher compared to concurrent plasma levels. Severe neurotoxicity occurred at the higher doses used. Due to limited diffusion and extremely low doses which could be used without life-threatening neurotoxicity, VP-16-213 does not appear to be a useful agent for intrathecal administration.

Ras proteins are essential and selective for the action of insulin-like growth factor 1 late in the G1 phase of the cell cycle in BALB/c murine fibroblasts

BALB/c 3T3 cells (A31 cells) require the sequential action of growth factors in order to proliferate from a quiescent growth state. Insulin-like growth factor I (IGF-I) is needed late in the G1 phase of the cell cycle, a time at which expression of the c-Ha-ras protooncogene is near maximal. An anti-ras antibody, introduced by microinjection, specifically blocked the ability of IGF-I to stimulate initiation of DNA synthesis. The antibody was specific for IGF-I; it failed to block serum, platelet-derived growth factor, or epidermal growth factor from inducing c-fos mRNA. By contrast, an anti-G alpha-subunit antibody had no effect on IGF-I-stimulated DNA synthesis but inhibited the induction of c-fos mRNA by platelet-derived growth factor or epidermal growth factor. BPA31 cells are tumorigenic A31-derived cells that progress through G1 in the absence of IGF-I. BPA31 cells produced an autocrine IGF-I that was responsible for the loss of late G1 control; the anti-ras antibody arrested the growth of these cells in late G1. The results suggest that ras proteins are essential for an IGF-I-sensitive, G1 control point.

[Determination of tetramethylpyrazine in traditional Chinese medicines by high performance liquid chromatography]

This paper reports a method for determining tetramethyl pyrazine in pilules, injections and extracts of Ligusticum chuanxiong by high performance liquid chromatography. The results showed the recovery rate to be higher than 97% and the coefficient of variation (CV) to be 1.39% (with in day) and 1.51% (day to day). The lowest detection amount was 0.005 micrograms. The method was easy, fast and accurate.

Complex amplitude reflectance of the liquid crystal light valve

The complex amplitude reflectance of the liquid crystal light valve (LCLV) is determined as a function of the writing intensity and applied voltage using an approximate model. The input and output polarizers are assumed to have arbitrary directions. The theoretical results based on this model match our experimental measurements. This theory allows us to optimize the operation of the LCLV as an intensity or phase-only spatial light modulator. When the polarizers are orthogonal and the input polarizer is at -34 degrees with the front liquid crystal director, the intensity reflectance reaches 100% (compared to 81% for the conventional configuration). Phase-only modulation is realizable by use of appropriate applied voltage bias and configuration of polarizers.

Phase I clinical trial and pharmacokinetic evaluation of 4'-0-tetrahydropyranyladriamycin (THP-adriamycin)

Tetrahydropyranyladriamycin (THP-adriamycin) is an anthracycline analogue currently under development in Europe and Japan. Preclinical studies suggest that it may have greater activity and less cardiac toxicity than doxorubicin. We conducted a phase I clinical and pharmacologic study of THP-adriamycin given as a weekly 15-min infusion for 3 weeks, followed by 1 week of observation. Therapy was associated with minimal acute toxicity. The dose-limiting toxicity was neutropenia, usually maximal during the 4th week after treatment; alopecia was rare. The maximum tolerated dose was 25 mg/m2; for phase II studies using this schedule, a dose of 20 mg/m2 weekly for 3 weeks is recommended. Pharmacokinetic studies revealed a triphasic elimination of the parent compound with alpha, beta, and gamma half-lives of 5.6 min, 1.4 h, and 9.3 h, respectively. THP-adriamycin was rapidly taken up by blood cell components, with concentrations in red blood cells (RBCs), lymphocytes, and polymorphonuclear cells exceeding those in plasma. In all, less than 10% of the compound was eliminated in the urine within 24 h.

Genotoxicity of [1H]benz[de]isoquinoline-1,3[2H]dione,5 amino-2-,[2-dimethylamino) ethyl] (BIDA) in human lymphocytes

We have investigated the genotoxicity of BIDA in cultured human lymphocytes. Lymphocytes were cultured and stimulated with phytohemagglutinin (PHA) for 72 h. Doses of 0.1, 0.25, 0.5, 0.75, and 1 microgram/ml of BIDA were added to the culture at 1 h (G2 phase), and 6 h (S/G2 phase) before harvesting. Cells were harvested at the end of the 72-h culture period with 1-h colcemid treatment to accumulate mitosis, and further prepared by standard cytogenetic technique. BIDA induced chromatic type breakages and chromatid exchanges at both 1 h and 6 h. The mean number of breakages per cell was 0, 0.1, 1.0, and 1.7 after treatment with 0.1, 0.25, and 0.75 micrograms/ml, respectively. Ai 1 microgram/ml, BIDA severely inhibited cell progression and very few mitoses were observed. At 6 h the mean number of breakages per cell was 0.3 at 0.25 microgram/ml and 1.2 at 0.5 microgram/ml. Very few cells entered mitosis at 0.75 and 1 microgram/ml. To study the effect of BIDA on cells in G0 and G1, BIDA (0.75 microgram/ml) was added for 1 h to the cultures at the beginning of culture (G0), or 24 h after (G1) culture initiation. Afterward, cells were washed and reincubated in the conditioned medium for 71 or 47 h. No chromosomal aberrations were seen in these experiments. The number of chromatid breaks was minimal (0.1 to 0.4/cell). Our study suggests that BIDA induces chromatid type aberrations during G2 and S phases. The absence of chromosome type aberrations in cells treated during G0 and G1 suggests that either BIDA has no effect on these cells or that damaged cells fail to progress through S and G2 to reach mitosis.

Pharmacokinetics of Amonafide in dogs

Amonafide, one of a series of imide derivatives of 1,8-naphthalic acid synthesized by Brana et al. has shown significant antitumor activity against a variety of experimental tumors, including L1210 leukemia and P388 leukemia. Along with the clinical trial at our institute, we have studied the disposition of Amonafide in dogs by HPLC and fluorometry. Six dogs received Amonafide i.v. at 5 mg/kg (100 mg/m2) over 15 min; three were sacrificed at 6 h, and three at 24 h. The initial plasma t1/2 of Amonafide was 2.4 +/- 0.4 min, the intermediate t1/2, 26.8 +/- 3.7 min, and the terminal t1/2, 21.7 +/- 4.0 h. The peak plasma concentration achieved was 6.3 +/- 1.7 micrograms/ml. The average apparent volume of distribution was 12.84 +/- 0.54 1/kg, and the total clearance was 0.56 +/- 0.16 1/kg/h. In 24 h, 9.5% +/- 0.2% of the administered dose was excreted in the urine as the parent drug, and 7.4% +/- 1.4% in the bile in 6 h. Amonafide penetrated the CSF readily and achieved the highest concentration 20-25 min after administration, which was 30% of the concurrent plasma level. Amonafide underwent extensive metabolism to at least three major metabolites and two or more minor metabolites. The alpha and beta plasma t1/2 of the major metabolite, an N-oxide derivative, were 24.8 min and 28.6 h, respectively. The 24-h cumulative urinary excretion was 1.4% of the injected dose, and the cumulative biliary excretion was 16.7% in 6 h. At autopsy 6 h after dosing, the liver contained the highest percentage (0.23% of administered dose) of unchanged Amonafide, followed by the stomach (0.11%), lung (0.04%), kidney (0.04%), and pancreas (0.03%). The rest of the major organs retained less than 0.02% of the Amonafide dose. One day after dosing, no detectable amount of Amonafide was found in any of these tissues, indicating that Amonafide appears to be extensively metabolized and not significantly retained in the dog.

Pharmacokinetics of homoharringtonine in dogs

We studied the pharmacokinetics and distribution of homoharringtonine (HHT), an antitumor alkaloid, in anesthetized dogs using chromatographic and radiochemical techniques. Uniformly tritiated HHT was administered i.v. to five dogs at doses of 0.05 to 0.34 mg/kg, 200 microCi per animal. Unchanged HHT disappeared in a triphasic manner from the plasma with an initial plasma t1/2 of 9.4 +/- 4.2 min, an intermediary t1/2 of 1.4 +/- 0.5 h, and a terminal t1/2 of 40.6 +/- 4.6 h. The plasma clearance was 114.0 +/- 20.1 ml/kg-1 h-1 and the steady-state volume of distribution was 6.2 +/- 0.7 1/kg. In 72 h, 40.1% +/- 4.0% of the administered radioactivity was excreted in the urine, 17.8% +/- 2.7% of which was unchanged HHT. HHT was metabolized extensively to one major and two minor metabolites. Biliary excretion of total radioactivity was 14.4% in 5 h, 2% of which was HHT. HHT concentration in the CSF was highest 4 h after drug administration, about 40% of the concentration in the concurrent plasma. At autopsy 5 h after dosing, the highest percentage of HHT was in the liver (7.4%), followed by the small intestine (2.5%), stomach (1.0%), pancreas (0.8%), kidneys (0.8%), and lungs (0.7%). The heart, spleen, large intestine, and brain each retained less than 0.5%. However, 24 h after dosing, 4% of the HHT still remained in the liver, 1% in the small intestine, and less than 1% in the other organs. HHT seems to be extensively metabolized in dogs and partially retained in the body.

Pharmacokinetics and metabolism of the antitumor drug amonafide (NSC-308847) in humans

Pharmacokinetics and urinary excretion of Amonafide (5-amino-2-[2-(dimethylamine)ethyl]-1H-benz[de]isoquinoline-1,3-(2H)- dione) were examined in seven patients who were administered 400 mg/m2 of drug as a 30-min infusion on a daily schedule for 5 consecutive days. Amonafide concentrations in plasma and urine were determined using reversed phase HPLC. Amonafide was eliminated from plasma with a terminal half-life of 3.5 hr. Renal excretion accounted for 23% of the administered dose. Amonafide pharmacokinetic parameters after the initial dose (day 1) were similar to those calculated after the fifth daily dose. Amonafide undergoes a significant amount of metabolism and eight urinary metabolites have been identified using a thermospray liquid chromatography-mass spectrometry (LC/MS) technique. Various N-acetylated species appear to be the major metabolites, although no evidence of N-acetylation was found in urine obtained from two patients. Two of the primary metabolites, the N(N5)-acetyl and N'(N1)-oxide metabolites of Amonafide, were tested in vitro for cytotoxicity against P388 murine leukemia cells. In this test system, the N-acetyl metabolite was observed to be only slightly less cytotoxic than the parent compound. The N'-oxide of Amonafide, however, proved to be inactive. These results are discussed together with the pharmacokinetic and metabolism data of this new investigational antitumor drug.

Central nervous system (CNS) penetration of homoharringtonine (HHT)

Generally tritiated homoharringtonine ([3H]HHT, 150 microCi, 430 micrograms) was administered intravenously to seven patients at varying times before surgical resection of malignant brain tumor. Plasma, urine, cerebrospinal fluid (CSF), and tumor specimens were obtained during surgery, and the concentrations of HHT, its major metabolite, and [3H]HHT equivalent were determined chromatographically and radiochemically. For [3H]HHT equivalent, the concentration in tumor ranged from 0.6 to 4.3 ng/g and the ratio of tumor to plasma concentration from 0.5 to 1.8. In one patient who had CSF available for drug determination, the CSF to plasma ratio of total [3H]HHT was 0.3 at 45 minutes after drug administration and less than 0.2 ng/ml was unchanged HHT. For unchanged HHT, drug concentration in tumor ranged from undetectable (4 patients) to 1.8 ng/g. A major metabolite of HHT was detectable in the tumor specimens of all the patients. These results indicate that homoharringtonine can penetrate into brain tumors; in 3 patients with brain tumors, the ratios of HHT concentration in the tumor to that in the concurrent plasma were greater than one.

Comparison of CNS penetration, tissue distribution, and pharmacology of VP 16-213 by intracarotid and intravenous administration in dogs

Eight beagle dogs received [3H]VP 16-213 at 2 mg/kg administered intravenously (IV) or intra-arterially (IC) through a catheter inserted into the internal carotid artery. Blood, urine, bile, and cerebrospinal fluid (CSF) samples were collected at intervals. At 1, 6, 24 hr, and 2 weeks after drug administration the dogs were sacrificed and the major organs analyzed for drug concentration. VP 16-213 concentration was determined by radiochemical assay and high pressure liquid chromatography. The plasma t1/2 in the IC group of dogs was 1.0 hr, the volume of distribution was 1.7 L/kg and the clearance was 1.5 ml/hr/kg. In the IV group the values were 1.7, 3.9, and 1.6, respectively. The CSF concentration peaked at 1 hr by both routes, but was higher at all time points in the IC group. At 24 hr and 2 weeks after IC VP 16-213, drug concentration in brain tissue was at least four times higher in the IC group compared with the IV group. In extracranial organs the reverse was true, with the bone marrow cell concentration 1.6 times higher by IV compared to IC (267.2 ng/g and 164.5 ng/g, respectively). Two major and one minor metabolites were found in plasma, urine, bile, and tissue by both routes, however, not all metabolites were found in all organs and body fluids. No acute neurologic toxicity was noted in the IC group and no histopathologic changes by light microscopy were found in the brain or other organs. IC VP 16-213 produced higher drug concentration in the brain of dogs compared with IV administration and was well tolerated at the dosage used.

Biochemical pharmacology of N-acetyl-N-(methylcarbamoyloxy)-N'-methylurea (caracemide; NSC-253272)

Preclinical pharmacologic studies of caracemide [N-acetyl-N-(methylcarbamoyloxy)-N'-methylurea; CAR] have demonstrated a marked instability of this compound in the presence of either phosphate buffer (pH 7.4) or human plasma. Using [1-14C-acetyl]CAR and [3H-methylcarbamoyloxy]CAR, three CAR degradation products were identified: product A, N-(methylcarbamoyloxy)acetamide; product B: N-(methylcarbamoyloxy)-N'-methylurea; and product C: N-hydroxy-N'-methylurea. CAR degradation in human plasma was demonstrated by high-performance liquid chromatography (HPLC) to occur in a time- and temperature-dependent manner. A 30-min incubation (37 degrees) of CAR (10(-4) M) with human plasma resulted in degradation of more than 55% of parent compound; at 1 hr, more than 75% of original CAR was degraded. Incubation of [1-14C-acetyl]CAR with rat brain homogenate resulted in the formation of 14CO2. This reaction was partially inhibited by coincubation with physostigmine (10(-3) M). CAR inhibited acetylcholinesterase activity in neuroblastoma cells with an IC50 of 14 microM. In mechanism of action studies, CAR was found to inhibit ribonucleotide reductase activity but only at nine times the IC50 of hydroxyurea. In contrast to hydroxyurea, CAR was found to be non-cell-cycle phase-specific and non-cross-resistant with two CHO cell lines resistant to hydroxyurea. These data demonstrate the instability of CAR; moreover, they suggest that its mechanism of cytotoxicity is distinctly different from that of hydroxyurea and that the neurotoxicity associated with CAR administration may be caused in part by inhibition of acetylcholinesterase activity.

Clinical pharmacology of 4-demethoxydaunorubicin (DMDR)

DMDR, a daunorubicin derivative with a higher therapeutic index and lower cardiotoxicity than either the parent drug or doxorubicin, is active when given PO in experimental animals. We studied its pharmacokinetics in ten patients receiving DMDR IV or PO or IV and PO sequentially at 10-12.5 mg/m2. DMDR and its metabolites were quantified by high-performance liquid chromatography and fluorometry. In nine patients who received DMDR IV the unchanged drug disappeared from the plasma biphasically with a mean terminal half-life of 27.0 +/- 5.5 h, an apparent volume of distribution of 63.9 +/- 12.61 kg-1, and a total clearance of 1.9 +/- 0.41 kg-1 h-1. In 24 h only 5.1% +/- 1.1% of the dose was excreted in the urine. In comparison, in 19 studies the plasma half-life of DMDR given PO was 34.8 +/- 6.7 h, 2.3% +/- 1.3% was excreted in the urine in 24 h, and the maximum plasma drug concentration was reached in about 1 h. The bioavailability of DMDR given PO was about 39% according to comparison of the areas under the plasma DMDR concentration versus time curves for the two routes, but 45% according to comparison of the 24-h cumulative urinary excretion rates. In one patient with severe liver dysfunction following oral administration, the plasma DMDR half-life was 56.8 h, more than twice the average length. By either route, the drug was quickly metabolized to one major metabolite, DMDR-ol. The plasma half-life of DMDR-ol was 72.5 +/- 24.7 h, or 35.7 +/- 7.4 when DMDR was administered IV or PO. In the plasma, DMDR-ol always exceeded DMDR in concentration. Moreover, the 24 h cumulative urinary excretion of DMDR-ol as a percentage of the dose of DMDR administered was 7.8 following IV and 7.4 following PO administration.

Clinical pharmacology of intracarotid etoposide

Pharmacokinetics studies were performed in ten patients who received VP-16 by intracarotid infusion at 100-300 mg/m2. VP-16 was analyzed by high-pressure liquid chromatography. ESTRIP and NONLIN were used to characterize VP-16 pharmacokinetics. VP-16 disappeared biphasically, with a t1/2 beta of 6.1 +/- 1.4 h; the total clearance was 26.8 +/- 2.8 ml/min/m2, and the Vss was 8.8 +/- 1.6 l/m2. The pharmacokinetics was not significantly different after administration by the IV route. However, at a lower dosage, less than 140 mg/m2, the half-life appears to be shorter. This may or may not be significant, since VP-16 pharmacokinetics is quite variable and the number of patients studied is relatively small. Overall, the brain and brain tumor do not appear to have any first-pass effect on VP-16 pharmacokinetics.

Clinical pharmacokinetics of 9, 10-anthracenedicarboxaldehyde-bis [(4,5-dihydro-1 H-imidazol-2-yl)hydrazone]dihydrochloride

We studied the clinical pharmacokinetics of the anthracene derivative bisantrene using high-performance liquid chromatographic analysis. We administered the drug to ten patients at 120-250 mg/m2 IV; one of these patients also received a second dose of 120 mg/m2 6 weeks later, and another received 150 mg/m2 weekly for three doses. Bisantrene disappeared from the plasma biphasically, with an initial t1/2 of 0.6 +/- 0.3 h and a terminal t1/2 of 24.7 +/- 6.9 h after single doses. The apparent volume of distribution according to the area under the curve was 42.1 +/- 5.9 l/kg, and the total clearance was 1045.5 +/- 51.0 ml/kg/h. The 96-h cumulative urinary excretion was 3.4% +/- 1.1% of dose; thus, renal excretion was a minor route of elimination for this agent. Bisantrene pharmacokinetics in the patient who received a second dose after 6 weeks showed insignificant changes. However, in the patient who was given this drug weekly for 3 weeks, the plasma t1/2 of the drug during the terminal phase became increasingly longer, while the total clearance was significantly reduced. These results suggest that bisantrene may accumulate in the body and that caution is essential in the event of frequent administration.

Central nervous system pharmacology of Baker's antifolate (NSC139105) in man

Radiolabelled Baker's Antifolate (BAF) was administered to 6 patients undergoing surgical resection of intracerebral tumors. Levels of radioactivity in resected tumor and edematous brain adjacent to tumor were generally higher than levels in concurrent plasma samples and were generally comparable to levels in temporalis muscle. Levels in tumor cyst fluid were far lower than concurrent plasma levels and levels in surrounding tumor. Chromatography was performed on tumor from 2 patients and revealed that only a small proportion of the radioactivity represented unchanged BAF. The major metabolite present in tissues was 1 000 times less potent as an inhibitor of dihydrofolate reductase than was BAF. Five patients had cerebrospinal fluid (CSF) sampled following administration of tracer doses of radiolabelled BAF. Radioactivity levels were far lower in CSF than in plasma. Levels of radioactivity in the CSF were also far lower than levels in tumor and brain samples from other patients and were slightly lower than tumor cyst fluid levels. Two patients had CSF collected after they received therapeutic doses of BAF. In these patients, both CSF and plasma were assayed using a dihydrofolate reductase inhibition assay. As with tracer dose studies, CSF concentrations of BAF were substantially lower than were concurrent plasma concentrations. Thus it appears that only very low concentrations of BAF are attainable in human CSF and intracerebral tumor, although a metabolite which is a very weak inhibitor of dihydrofolate reductase attains high concentrations in tumor.

Phase I study of tricyclic nucleoside phosphate using a five-day continuous infusion schedule

A Phase I trial of tricyclic nucleoside phosphate (1,4,5,6,8-pentaazaacenaphthylene-3-amino-1, 5-dihydro-5-methyl-1-beta-D-ribofuranosyl 5'-phosphate ester; NSC 280594) was conducted using a 5-day continuous infusion schedule. Thirty-seven patients with advanced cancer were entered on the study, of whom 33 patients were evaluable for response and toxicity. Dose levels ranged from 10 mg/sq m/day X 5 days to 40 mg/sq m/day X 5 days. Initially, courses were repeated every 3 to 4 weeks. As cumulative toxicity became manifested, the interval between courses was changed to every 6 weeks. Major toxicities included hyperglycemia, hepatotoxicity, and thrombocytopenia. Patients with a prior history of diabetes mellitus, extensive radiation therapy, or significant liver metastases were prone to severe toxicity. Other toxicities noted were nausea and vomiting, abdominal discomfort, anemia, and reduction in serum calcium, phosphorus, and albumin levels. Rare side effects included hypertriglyceridemia, hyperamylasemia, diarrhea, and stomatitis. Antitumor activity observed include improvement in s.c. metastases in a patient with papillary thyroid carcinoma, stabilization of disease in a patient with mesothelioma, and mixed responses in three patients (colon cancer, sarcoma, and tonsillar squamous cell cancer). Recommended schedule for Phase II studies is 20 mg/sq m/day for 5 days every 6 weeks.

Pharmacological disposition of 1,4-dihydroxy-5-8-bis[[2 [(2-hydroxyethyl)amino]ethyl]amino]-9,10-anthracenedione dihydrochloride in the dog

DHAQ, a new antitumor agent, has been selected for clinical trial on the basis of its activity against a number of transplantable rodent tumors. In anticipation of the clinical trial of this agent, the pharmacology of DHAQ was studied in beagles by high-pressure liquid chromatographic and radiochemical techniques that are specific for the unchanged drug. 14C-DHAQ was administered IV to beagles at a dose of 5 mg/kg, 100-125 microCi total. With a maximal plasma concentration of 75 +/- 2.7 ng/ml, DHAQ was eliminated from the plasma with a half-life of 28.1 h during the terminal phase. The total clearance of DHAQ was 10.1 +/- 0.4 mg/kg/min, while the apparent volume of distribution was 26.6 +/- 4.9 l/kg. In 48 h, 2.4% +/- 0.6% of the dose was excreted in the urine and 3.0% +/- 0.1% in the bile as the unchanged drug. At autopsy performed 5 h after dosing, the highest percentage of the administered DHAQ was in the liver (49.7% +/- 2.7%), followed by the small intestine (7.1% +/- 0.7%), kidneys (2.7% +/- 0.1%), lung (1.9% +/- 0.3%), spleen (1.6% +/- 0.3%), and stomach (1.3% +/- 0.1%). The heart, large intestine, pancreas, gallbladder, urinary bladder, and brain each retained less than 1% of the dose. However, 24 h after dosing 10.6% of the drug was detected in the liver and 2.9% in the small intestine. In terms of the percentage of the dose, the distribution of DHAQ in the other organs either remained unchanged or increased slightly. In concentrations varying from 10 ng/ml to 10 micrograms/ml the drug was 70%-80% bound to plasma protein. DHAQ was metabolized to two unidentified metabolites. Thus, this drug appeared to be cleared from the plasma of beagle dogs chiefly by tissue binding, leading to possible persistence of the drug in certain body compartments.

Human tissue distribution of 4'-(9-acridinylamino)-methanesulfon-m-anisidide (NSC 141549, AMSA)

Concentrations of AMSA were determined by HPLC in autopsy tissue samples from five patients who had received the drug antemortem. Relative organ concentrations of AMSA varied from patient to patient; however, concentrations were generally highest in gallbladder, liver, and kidney, while low levels were generally but not invariably found in lung, testicle, muscle, fat, spleen, bladder, pancreas, colon, prostate, and brain. One patient with ventricular fibrillation and seizures had high tissue AMSA concentrations in myocardium, but low concentrations in brain. Another patient with seizures during treatment had high brain concentrations of AMSA. Relative organ concentrations were similar to those found in mice, except that mice have high AMSA concentration in their spleens whereas our patients did not, even when the spleen was infiltrated with leukemic cells. High tissue concentrations of AMSA were still present 2 weeks after treatment. AMSA concentration was lower in a renal oncocytoma (1.1 micrograms/g) than in surrounding kidney (2.4 micrograms/g).

Clinical pharmacology of 2,5'-diaziridinyl-3,6-biscarboethoxyamino-1,4-benzoquinone (AZQ)

2,5'-Diaziridinyl-3,6-biscarboethoxyamino-1,4-benzoquinone (AZQ) is an alkylating compound which has exhibited a broad spectrum of antitumor activity against a variety of experimental tumors, particularly those implanted intracranially. We have studied the clinical pharmacology of AZQ in 11 patients with various types of tumors. AZQ was administered at 1-12 mg/m2 daily for 5 days by i.v. infusion in 10-30 min. 14C-labelled AZQ was given on day 1 only. Blood and urine specimens were analyzed radiochemically and chromatographically. The plasma disappearance of unchanged AZQ was essentially biphasic, with an initial plasma t 1/2 of 1.4 +/- 0.4 hr and a terminal t 1/2 of 45.5 +/- 3.1 hr. The apparent volume of distribution was 14.2 +/- 3.0 l/kg. The cumulative urinary excretion of unchanged AZQ was 4.3% in 24 hr and 8.6% in 96 hr. The total clearance of the drug was 200 ml/kg/hr. Cerebrospinal fluid AZQ concentration peaked 45-90 min after drug administration, reaching about 70% of that in plasma, and then declined at nearly the same rate.

Clinical pharmacokinetics of vinblastine by continuous intravenous infusion

Vinblastine (VLB) is moderately active clinically against advanced breast cancer. Since VLB is extensively taken up by platelets and thus only partially available to tumor cells, to enhance the therapeutic index of VLB we have therefore administered this agent by continuous i.v. infusion to patients with advanced breast cancer. In conjunction with the clinical trial, we conducted pharmacokinetic studies of generally tritiated VLB, using radiochemical and chromatographic techniques. The elimination of VLB from the plasma of patients who received it by 5-day i.v. infusion at 1 to 2 mg/sq m daily was biphasic. In four patients who achieved partial remission, the average plasma half-life of VLB during the terminal phase was 29.4 +/- 14.6 days, with a total clearance of 36 +/- 8 ml/kg/hr, and a steady-state apparent volume of distribution of 28.1 +/- 8.5 liters/kg. However, in three patients whose disease merely stabilized, the plasma half-life was 6.4 +/- 1.6 days, the total clearance was 137 +/- 2.9 ml/kg/hr, and the volume of distribution was 33.0 +/- 11.6 liters/kg. In contrast, in five patients with refractory disease, these parameters were 2.3 +/- 0.3 days, 541 +/- 124 ml/kg/hr, and 37.6 +/- 8.6 liters/kg. Since the apparent volumes of distributions at steady state did not differ significantly among these three groups, whereas the values of the total clearance were markedly dissimilar, the plasma half-lives of VLB were significantly shorter in patients not responsive to continuous infusion therapy with this drug. Although the number of patients studied was small, it nevertheless appears that favorable clinical response of patients with advanced breast cancer is associated with slow total clearance of the drug.