Antiblastic treatment of haematological malignancies during pregnancy: a crucial decision

Antiblastic treatment of hematological malignancies during pregnancy poses a number of issues related to the curability of the maternal disease, the need of a prompt treatment and the potential toxicity of chemotherapy for the fetus. Here we report the results of a systematic literature search about the management of the most frequent hematological malignancies that may occur during pregnancy, focusing on specific issues related to gestational age at diagnosis, fetal toxicity and efficacy on the maternal side. The standard approach in non-pregnant women is illustrated as reference.

Non-oxidized porous silicon-based power AC switch peripheries

We present in this paper a novel application of porous silicon (PS) for low-power alternating current (AC) switches such as triode alternating current devices (TRIACs) frequently used to control small appliances (fridge, vacuum cleaner, washing machine, coffee makers, etc.). More precisely, it seems possible to benefit from the PS electrical insulation properties to ensure the OFF state of the device. Based on the technological aspects of the most commonly used AC switch peripheries physically responsible of the TRIAC blocking performances (leakage current and breakdown voltage), we suggest to isolate upper and lower junctions through the addition of a PS layer anodically etched from existing AC switch diffusion profiles. Then, we comment the voltage capability of practical samples emanating from the proposed architecture. Thanks to the characterization results of simple Al-PS-Si(P) structures, the experimental observations are interpreted, thus opening new outlooks in the field of AC switch peripheries.

Pharmacogenomics panel test for prevention toxicity in patient who receive Fluoropirimidine/Oxaliplatin-based therapy

AIM

Both Fluoropirimidine and Oxaliplatin (FluOx) are the most common anticancer drugs used to treat lung, colorectal, ovarian, breast, head/neck, and genitourinary cancers. However, the efficacy of FluOx-based therapy is often compromised because of the severe risk of toxicity. Stratification of patients for multidrug response is a promising strategy for cancer treatment and personalized therapy.

METHODS

Here, we review the late findings on the most appropriate gene variants related to the toxicity in patients receiving FluOx chemotherapy. Several criteria were used to select a genotyping panel tests, including dihydropyrimidine dehydrogenase (DPYD), thymidylate synthase (TYMS), Glutathione S-transferase (GSTP1), and ATP-binding cassette, subfamily C member 2 (ABCC2).

RESULTS

Results of allelic status from 7 validated polymorphism assays, allow the stratification of the patients who are most likely to respond to FluOx treatments. Also, we will take in consideration the usefulness and costs of the methods used to detect these polymorphisms.

CONCLUSIONS

With these pharmacogenomics markers, the oncologists will have new means based on the genetic profile of the individual, to make treatment decisions for their patients in order to maximize benefits and minimize toxicity.

Knowledge and skills needs for health professions about pharmacogenomics testing field

BACKGROUND

Promise in the future, a disease could be ranked into genetic categories, allowing bespoke tailoring of medicine to maximize therapeutic effects and to reduce the potential for adverse drug response. This new feature requires for health professionals to have competencies not only for the basic skills of their discipline, but also for the understanding on why, when, and how that knowledge should be applied to improve personalized therapies for their patients. Current opinion on basic competences of health professions includes knowledge and skills on two fundamental features: (1) genetics of disease, to allow the understanding and the identification of diseases associated to genetic variations, and to facilitate the development of new genomic tests; and (2) ethical, social and economical implications that are fundamental to identify those factors that might contribute to a successful integration of pharmacogenomics into international health and public policy.

AIM

Briefly, we described (1) current knowledge on genetic variations that interact with therapies and the need to detect them; (2) the most common available methods for detecting mutations; and (3) ethical, social and economic issues related to pharmacogenetic testing and recording of genetic information (e.g., critical evaluation of the development of new tests, privacy, the current absence of public reimbursement, etc).

CONCLUSIONS

These could be useful recommendations for academic institutions and educational programs to prepare health professionals with the necessary abilities for their future practice.

Combination treatment of flag with non-pegylated liposomal doxorubicin (MYOCET(TM)) in elderly patients with acute myeloid leukemia: a single center experience

The incidence of acute myeloid leukemia (AML) increases with age, but results of intensive chemotherapy in elderly patients are disappointing. Non-pegylated liposomal formulations of doxorubicin (Myocet™) have been developed with the aim of reducing systemic and cardiac toxicity especially in the elderly. We evaluated the efficacy and toxicity profiles of fludarabine, cytarabine and granulocyte colony-stimulating factor (FLAG) regimen given in association with Myocet™ in 35 patients with AML, median age 69 years (range 61-83 years). Nineteen (54.3%) had newly-diagnosed AML, twelve (34.3%) patients had secondary AML (ten with Myelodisplastic Syndrome, two with Primary Myelofibrosis) and 4 (11.4%) patients had had a late relapse (>12 months) of AML. Complete remission (CR) and partial remission (PR) were obtained in twenty-two (63%) and 3 (8.5%) patients, respectively. Seven (20%) patients showed a resistant disease. There were 3 early deaths (8.5%). Six patients (17%) experienced severe cardiovascular toxicity. The median overall survival (OS) was 12 months (range 1-52 months) with a median disease-free survival (DFS) of 20 months (range 1-48 months). One-year and two-year DFS were 78.9% and 26.7%, respectively. This study demonstrates that in elderly patients with AML, FLAG-Myocet combination shows promising efficacy response with acceptable toxicity, enabling most patients to receive further treatments, including transplantation procedures.

Management of occult adrenocorticotropin-secreting bronchial carcinoids: limits of endocrine testing and imaging techniques

The differential diagnosis and the identification of the source of ACTH in occult ectopic Cushing's syndrome due to a bronchial carcinoid still represents a challenge for the endocrinologist. We report our experience in six patients with occult bronchial carcinoid in whom extensive hormonal, imaging, and scintigraphic evaluation was performed. All patients presented with hypercortisolism associated with high plasma ACTH values. The CRH test and high dose dexamethasone suppression test suggested an ectopic source of ACTH in three of six patients. During bilateral inferior petrosal sinus sampling, none of the patients showed a central to peripheral ACTH gradient. At the time of diagnosis, none of the patients had radiological evidence of the ectopic source of ACTH, whereas pentetreotide scintigraphy identified the lesion in two of four patients. Finally, a chest computed tomography scan revealed the presence of a bronchial lesion in all patients, and pentetreotide scintigraphy identified four of six lesions. In all patients a bronchial carcinoid was found and removed. In one patient with scintigraphic evidence of residual disease after two operations, radioguided surgery, using a hand-held gamma probe after iv administration of radiolabeled pentetreotide, was performed; this allowed detection and removal of residual multiple mediastinal lymph node metastases. In conclusion, our data show that there is not a single endocrine test or imaging procedure accurate enough to diagnose and localize occult ectopic ACTH-secreting bronchial carcinoids. Radioguided surgery appears to be promising in the presence of multiple tumor foci and previous incomplete removal of the tumor.

Microdialysis study of bromocriptine and its metabolites in rat pituitary and striatum

Bromocriptine, a D2 receptor agonist, was administered intravenously (1mg/kg) to anesthetized rats. Microdialysis probes were implanted in the pituitary and the striatum, known sites of D2 agonist action. Bromocriptine and its metabolites were monitored in plasma and tissue dialysates for 4 h. Drug analyses were performed using two different enzyme immunoassays specific for untransformed bromocriptine or a pool of parent drug plus hydroxylated metabolites. The metabolites/parent drug ratio for areas under the curve was 5.5 in plasma and 1 in the pituitary. No metabolites could be detected in the striatum. Bromocriptine penetration was at least 10-fold greater in the pituitary than in the striatum. The kinetics of bromocriptine in the pituitary and striatum did not parallel those in plasma, indicating that the prolonged action of bromocriptine reported by other authors may be due to slow dissociation from receptors.

Bromocriptine modulates P-glycoprotein function

The multidrug resistance (MDR)-associated P-glycoprotein (P-gp) is a membrane transporter which carries, at the expense of MgATP hydrolysis, many amphiphilic molecules, such as the MDR-related cytotoxic drugs vincristine and vinblastine, and the MDR-reversing agents verapamil and progesterone. We have tested the effects on P-gp function of bromocriptine (BCT), an ergot alkaloid known as a D2 dopaminergic receptor agonist. BCT (at 4 microM) partially reverses the P-gp-mediated vincristine resistance of the Chinese hamster lung fibroblasts DC-3F/ADX, a MDR cell line. P-gp containing membrane vesicles prepared from the DC-3F/ADX cells exhibit, in the absence of any added drug, a basal MgATPase activity due to P-gp. BCT inhibits this basal ATPase activity, with a half-inhibiting concentration of 0.30 +/- 0.15 microM. BCT also inhibits the verapamil-induced P-gp ATPase stimulation competitively (Ki approximately 0.2 microM), and the progesterone-induced P-gp ATPase stimulation non-competitively (Ki approximately 0.07-0.10 microM). BCT also non-competitively inhibits the vinblastine-dependent P-gp ATPase activity within the same concentration range. Hydroxylated metabolites of BCT have different effects on P-gp ATPase, only the monohydroxylated being able to modulate both the basal and the drug-stimulated ATPase activities. In conclusion, these effects of BCT on P-gp function can be linked to a specific interaction with P-gp, probably involving inhibition of P-gp-mediated drug transport.

Metabolite involvement in bromocriptine-induced prolactin inhibition in rats

Bromocriptine (BCT) is a dopamine D2 receptor agonist used for the treatment of Parkinson's disease and hyperprolactinemic disorders. After oral administration, BCT is metabolized into mono- or dihydroxylated metabolites. To study how these metabolites influence parent drug pharmacodynamics, we administered BCT to rats intravenously (1 mg/kg i.v.) and orally (10 mg/kg p.o.) and measured the inhibition of prolactin secretion. Despite similar areas under the curve for BCT, the duration of the effect was 36 h after oral and only 18 h after intravenous administration. Pharmacokinetic/pharmacodynamic models were used to correlate the concentration of BCT in the effect compartment with the lowering of prolactin. One of these models (effect compartment model) showed that the effective concentration (EC50) at the site of action was much lower after oral (0.56 nM) than after intravenous administration (3.68 nM). In contrast, the EC50 values based on BCT metabolite data were in the same range for both administrations. These observations suggested the activity of one or more BCT metabolites. To confirm this hypothesis, hydroxylated metabolites of BCT (produced in vitro by rat liver microsomes) were administered i.v. (100 microg/kg) in rats. We found that monohydroxylated BCT was able to lower prolactin secretion like BCT. Dihydroxylated metabolites, as well as monohydroxylated metabolites, were effective in reducing in vitro prolactin secretion. Because we demonstrated that the concentration of hydroxylated metabolites after oral administration is 55-fold that of BCT, it can be concluded that BCT activity in the pituitary after oral administration is mediated by its metabolites.

Effect of variability of plasma interferences on the accuracy of drug immunoassays

Most immunoassays applied to drugs in human plasma do not use an extraction of analyte. To compensate for interferences due to plasma proteins or salts, standards are prepared in drug-free plasma. Because the concentration of plasma components varies from one subject to another, it is likely that the drug-free plasma is not representative of the potential interference in each plasma. Using two immunoassays, for a steroid (nomegestrol acetate) and a heptapeptide (BN 52080), the authors have shown that tracer binding to the antibody may vary significantly between plasma from different subjects. Intersubject variability of tracer-antibody binding was 21.6% (coefficient of variation for 25 subjects) for nomegestrol acetate. When the same plasma were spiked with the steroid at a concentration corresponding to the central part of the standard curve, the recovery was between 39 and 215%. Intersubject variability in tracer binding was lower (7.7%) for the peptide immunoassay, but still affected accuracy. The authors show that this problem is common to direct immunoassays for other drugs and must be solved in assay development.

Enzyme immunoassays for bromocriptine and its metabolites

We have developed two bromocriptine enzyme immunoassays with different specificities for applications in human and animal pharmacokinetic studies. The first assay uses antibodies directed against the cyclopeptide structure of bromocriptine, and is specific for untransformed bromocriptine. The second assay uses antibodies directed against the bromolysergic part of the molecule and allows the measurement of both bromocriptine and its metabolites. Enzymatic tracers were obtained by covalent coupling of bromocriptine analogs to acetylcholinesterase from the electric eel Electrophorus electricus. Both assays have a limit of detection of 10 pg/ml and a limit of quantification of 50 pg/ml. The specificity of the assays was determined following fractionation by high-performance liquid chromatography of rat samples obtained after administration of bromocriptine.

Study of mediators of anaphylaxis in nasal wash fluids after aspirin and sodium metabisulfite nasal provocation in intolerant rhinitic patients

Nasal histamine (H), leukotriene C4 (I-LTC4) and SRS-A activity were studied in seven aspirin-(ASA)-intolerant patients (AIR) with rhinitis and in five ASA-tolerant control patients with chronic rhinitis after nasal provocation (NP) with a lysine acetylsalicylate solution. The same parameters were also studied after metabisulfite (MBS) NP in four sulfite-intolerant patients with rhinitis and in six control patients with chronic rhinitis. In six ASA-intolerant subjects and in four controls, we studied the PGD2 levels in nasal washes after ASA NP 0.2 mL of lysine acetylsalicylate solution (10 mg/mL) was sprayed intranasally in ASA-intolerant patients and controls and a 25-mg/mL MBS solution in sulfite intolerant patients and controls. Nasal wash fluids were obtained using 5 mL of 0.15 M saline before and 7 1/2, 15, 30, and 60 minutes after nasal provocation. The nasal provocation with ASA induced itching and sneezing in four out of seven intolerant subjects. In this subgroup histamine values in nasal wash fluids were significantly higher versus the remaining ASA-intolerant patients at 30 and 60 minutes (P less than .05 and P less than .01, respectively) and versus controls at 60 minutes (P less than .01). We found significantly higher I-LTC4 (P less than .01) and SRS-A levels in nasal washes collected from ASA-intolerant subjects versus controls at 60 minutes after nasal provocation. There was no significant increase in the mean PGD2 values in either the ASA-intolerant or control groups.(ABSTRACT TRUNCATED AT 250 WORDS)

[Radiation-induced intestinal injuries]

Postoperative radiation after the removal of radiosensitive tumours may cause acute or chronic intestinal lesions. In some cases severe complications requiring one or more operations may arise even years later and unfortunately the morbidity and mortality rates are high. The paper presents a discussion of the clinical onset of these pictures as well as diagnostic and therapeutic possibilities in the light of personal experience and information obtained from the literature.

A tetrodotoxin-like substance found in the Brazilian frog Brachycephalus ephippium

A tetrodotoxin-like substance, denoted ephippiotoxin, was obtained from the tissue of Brachycephalus ephippium, a small pumpkin-coloured frog collected in the Atlantic Forest of the southeast region of Brazil. Ephippiotoxin is a dialyzable substance soluble in water, methanol and ethanol, but insoluble in organic solvents such as chloroform and other apolar solvents. After treatment with active charcoal (Norit-A) and purification with ion-exchange Amberlite IRC-50 resin (NH4 + form), a freeze-dried residue was obtained, with a toxicity of c. 117 micrograms/kg (mice, i.p.). Ephippiotoxin showed the same mobility as crystalline tetrodotoxin (Sankyo) when submitted to thin-layer chromatography (silica gel G) using seven different solvent systems. White mice (20 +/- 1 g) injected i.p. with either B. ephippium tissue extracts or semi-purified toxin showed partial paralysis of the hind limbs, lethargy, altered breathing rhythm and clonic convulsions. Death occurred within 1.5-30 min after injection, depending on the dose. Ephippiotoxin induced atrioventricular diastolic blockade in the toad heart. It also inhibited the response of toad striated muscle to direct and indirect electric stimulation and blocked the compound action potential of isolated frog sciatic nerve.

Early detection of pregnancy by new beta-hCG monoclonal urine test

1,066 urine samples were assayed by beta-human chorionic gonadotrophin (beta-hCG) monoclonal pregnancy test with a sensitivity of 150 IU hCG/l. Tests were performed in 5 independent laboratories and results were compared with those of pregnancy tests which were used routinely. Urine samples which showed discordant results under evaluation were reassayed for beta-hCG using radioimmunoassay. 569 urine samples were from nonpregnant women, and a consistent result with comparison pregnancy tests was achieved in 97.19% of urine samples. The trial test from 389 urine samples of pregnant women was 99.49% in accordance with routine pregnancy tests. Results from 108 urine samples of women over 40 years of age indicate the high specificity of the new beta-hCG monoclonal pregnancy test. Titration experiments showed 63% positive tests at 150 IU beta-hCG/l. Data presented combine to suggest that this new monoclonal pregnancy test is a valuable aid in diagnosing early pregnancy. It may also be used in the diagnosis of tubal pregnancy and in other ectopic processes.

A study on melanophore receptors of Papiliochromis ramirezi (Teleostei, Cichlidae)

Melanophores of Papiliochromis ramirezi aggregate their melanosomes in the presence of catecholamines. Their order of potency are: at 10(-4) M, norepinephrine greater than isoproterenol = epinephrine; at 10(-6) and 10(-8) M, norepinephrine = isoproterenol greater than epinephrine. These effects are antagonized not only by phentolamine but also by propranolol. The catecholamines are unable to induce pigment dispersion. Melanosome dispersion is obtained with cholinergic drugs and the order of potency is nicotine greater than acetylcholine = pilocarpine. Their effects are inhibited by atropine and also by d-tubocurarine and potentiated by physostigmine. The evidences suggest the presence of undifferentiated adrenoceptors, related to the melanosome aggregation and undifferentiated cholinoceptors related to the melanosome dispersion.

Detection of morphine in urine by hemagglutination inhibition, with use of lyophilized reagents

We describe a modified test of hemagglutination inhibition for the detection of morphine in urine, similar to the well-known test for pregnancy. The reaction takes place in test tubes or ampoules containing carefully matched amounts of lyophilized morphine antiserum and tanned human erythrocytes coated with morphine conjugated to rat serum albumin. The reagents are reconstituted by adding 100 microL of urine and 400 microL of water, and the result is read after 60 min. The detection limit, tested with the method of Gorodetzky (Clin Chem 19:753, 1973), was about 200 ng of total morphine per milliliter of urine. For more than 2000 samples, results by our test agreed satisfactorily with those obtained by an accepted RIA method. The test is suitable for rapid screening in field work, monitoring subjects during detoxication, and use in nonspecialized laboratories. Confirmatory analysis is needed for quantitative measurements, forensic purposes, and discrimination between morphine and cross-reacting opiates.

Detection of morphine in urine by hemagglutination inhibition, with use of lyophilized reagents

We describe a modified test of hemagglutination inhibition for the detection of morphine in urine, similar to the well-known test for pregnancy. The reaction takes place in test tubes or ampoules containing carefully matched amounts of lyophilized morphine antiserum and tanned human erythrocytes coated with morphine conjugated to rat serum albumin. The reagents are reconstituted by adding 100 microL of urine and 400 microL of water, and the result is read after 60 min. The detection limit, tested with the method of Gorodetzky (Clin Chem 19:753, 1973), was about 200 ng of total morphine per milliliter of urine. For more than 2000 samples, results by our test agreed satisfactorily with those obtained by an accepted RIA method. The test is suitable for rapid screening in field work, monitoring subjects during detoxication, and use in nonspecialized laboratories. Confirmatory analysis is needed for quantitative measurements, forensic purposes, and discrimination between morphine and cross-reacting opiates.