Magnetic nanoparticle decorated anodic alumina nanotubes for fluorescent detection of cathepsin B.

In this work, we present the process to provide anodic alumina nanotubes with magnetic responsivity based on magnetic nanoparticles. We demonstrate the possibility to cause the motion of these composite nanotubes under magnetic field, providing them with guided mobility. The obtained magnetic anodic alumina nanotubes are completely characterized and their potential to undergo selective and effective functionalization, and stimuli-responsive load release is demonstrated. For this purpose, protease-triggered release of fluorescent molecules loaded inside the magnetic anodic alumina nanotubes (MAANTs) by selective functionalization is performed. The inner walls of the MAANTs were selectively covered with protein padding of albumin-fluorescein isothiocyanate conjugate (FITC-BSA) through means of silanization. Protein functionalization was designed to undergo proteolytic hydrolysis in presence of cathepsin B- protease highly expressed during growth and initial stages of tumor metastasis - in order to cleave peptide bond of albumin and release fluorescent fragments of the protein. Proteolytic reaction with the enzyme is performed under acidic conditions. Presented arrangement is an exemplary combination of functionalities - which are vast - and of value for applications like drug delivery and biosensing applications.

Allosteric enhancers of A1 adenosine receptors: state of the art and new horizons for drug development.

Adenosine is an important autocoid, exerting its physiological effects on the human body by activation of four different G-protein-coupled-receptors (GPCRs) classified as A(1), A(2A), A(2B), and A(3). These receptors are coupled to secondary messenger systems including adenylate cyclase, inositol phosphate metabolism, and K(+), K(ATP) and Ca(2+) channels. Pharmacological agents that increase the activation of A(1) adenosine receptors in response to adenosine would be useful for treatment of cardiovascular, central nervous system, and inflammatory pathologies. Compounds that are able to enhance the activity of the A(1)-adenosine receptors by the endogenous ligand within specific tissues may have potential therapeutic advantages over non-endogenous agonists. Such an opportunity for intervention is provided by the concept of allosteric modulation of GPCRs. Therefore the use of allosteric enhancers to increase the responsiveness of the A(1) receptors to endogenous adenosine at sites of its production is an appealing alternative to activation by exogenous agonists. This approach minimizes side effects because allosteric enhancers amplify the action of the agonist by stabilizing the agonist-A(1)-receptor-G protein ternary complex. The allosteric enhancement of the GABA(A) receptor by benzodiazepines is the most famous and successful example of this strategy. The aim of this article is to give an overview of the results obtained in this field and discuss the opportunities and challenges that this class of ligands might offer for medicinal chemistry and pharmacology.

Design, synthesis, DNA binding, and biological evaluation of water-soluble hybrid molecules containing two pyrazole analogues of the alkylating cyclopropylpyrroloindole (CPI) subunit of the antitumor agent CC-1065 and polypyrrole minor groove binders.

We have synthesized and evaluated a series of hybrids, denoted 22--27, for in vitro cytotoxic activity against a variety of cancer cell lines. These hybrids represent a molecular combination of polypyrrole minor groove binders structurally related to the natural antitumor agent distamycin A and two pyrazole analogues of the left-hand segment called cyclopropylpyrroloindole (CPI) of the potent antitumor antibiotic (+)-CC-1065. These novel water-soluble hybrids have been designed to enhance the minor groove binding ability of alkylating units 20 and 21, which should increase their clinical appeal by overcoming the administration problems of (+)-CC-1065 derivatives. The DNA alkylating and cytotoxic activities against several tumor cell lines are reported and discussed in terms of their structural differences in relation to both the number of N-methyl pyrrole rings and the type of the alkylating unit tethered to the oligopeptidic frame. It may be noted that, in general, and especially for 22--24, the cytotoxicity of the hybrids was much greater than that of the alkylating units alone. In only one case, compound 27, did the hybrid have cytotoxic activity comparable to that of the alkylating unit alone against FM3A/0 cells. The broadest spectrum of activity and greatest potency was shown by the hybrid 24, in which the alkylating unit 20 and the deformyl distamycin A are tethered by 1-methyl 2,5-dicarbonyl pyrazole, with IC(50) values for the different tumor cell lines ranging from 7 to 71 nM. For compounds 22--24, the increase of the length of the pseudopeptidic moiety from one to three N-methylpyrrole residues led to an increased cytotoxicity. Among the hybrids tested for their inhibitory effects on the proliferation of murine L1210 leukemia cell line, compound 24 proved to be the most active (IC(50) = 7.4 nM), and in the sequencing gel experiments, it showed the strongest and most highly sequence-specific DNA alkylation activity. For compounds 22-24, the sequence specificity of DNA alkylation appears to be affected by the modification of the number of pyrrole rings, and the correlation between cytotoxicity and alkylation pattern suggests that 24 exerts its cytotoxicity through DNA sequence-specific alkylation of the third adenine located in the sequence 5'-ACAAAAATCG-3'. The two other hybrids 22 and 23 were slightly less active for tumor cell proliferation, with IC(50) values of 58 and 19 nM, respectively. With only one exception, none of the compounds was endowed with antiviral activity at subtoxic concentrations. Compound 24 inhibited the effect of vaccinia virus at a concentration that was significantly lower than its minimum cytotoxic concentration for the E(6)SM host cells. These compounds gave distinct patterns of alkylation in AT-rich sequences, indicating that minor structural changes produced marked alterations in sequence selectivity.

Synthesis and biological effects of a new series of 2-amino-3-benzoylthiophenes as allosteric enhancers of A1-adenosine receptor.

New derivatives of PD 81,723, an allosteric enhancer of agonist binding to the A1-adenosine receptor, have been synthesized and evaluated in an intact cell assay. Compounds 3a, 3o and 3p appeared to be more potent than PD 81,723 and at a concentration of 0.1 microM caused significant reductions of cAMP content of CHO cells expressing the human A1-adenosine receptor. Compounds 4e and 4o appeared to be allosteric enhancers at a low concentration and antagonists at a higher concentration, whereas compounds 3c, 3g, 3s and 4l appeared to be weak antagonists that are also allosteric enhancers at the higher concentration of 10 microM.

Synthesis of conformationally constrained analogues of KN62, a potent antagonist of the P2X7-receptor.

Conformationally constrained analogues of KN62 containing 1,2,3,4-tetrahydro-7-hydroxyisoquinoline-3-carboxylic acid with S configuration in position 3 were synthesized and their antagonist activities were tested on human macrophage cells. While KN62 is a potent antagonist of the P2X7 receptor, these analogues were inactive as antagonists and only one compound showed appreciable activity as P2X7 antagonist, which was 30 times weaker than that reported for KN62.

Geiparvarin analogues. 3. Synthesis and cytostatic activity of 3(2H)-furanone and 4,5-dihydro-3(2H)-furanone congeners of geiparvarin, containing a geraniol-like fragment in the side chain.

Continuing our study on the structural features of geiparvarin (1), responsible for cytostatic activity, a series of 4,5-dihydro-3(2H)-furanones 10a-f and of 3(2H)-furanones 11a-f as well as 2",3"-dihydrogeiparvarin (14) have been designed and synthesized. Their cytostatic activity was evaluated against proliferation of murine (L1210, FM3A) and human (Raji, Molt/4F, and MT4) tumor cells. Modifications in the region of the olefinic double bond by introduction of the characteristic alkenyl side chain of ascofuranone (compounds 10a-f and 11a-f) markedly decreased the cytostatic activity as compared to geiparvarin itself, but this effect does not seem to be correlated to the presence of the furanone moiety linked to the alkenyl chain or to the ability to afford Michael type adducts. Replacement of the coumarin portion by other aromatic rings did not alter the cytostatic activity. The essential inactivity of 2",3"-dihydrogeiparvarin (14) points to the importance of the 3(2H)-furanone ring system in the cytostatic activity; consequently, this moiety may be considered as the determinant pharmacophore for antitumor activity, while the side chain plays a rather modulatory role.

New isoxazole derivatives of retinoids: synthesis and activity on growth and differentiation of tumor cells.

The effects of several newly synthesized isoxazole analogues of retinoids on differentiation and proliferation of 'in vitro' cultured tumor cell lines are reported. Some of the tested compounds exhibit significative differentiating action, inducing adipogenic conversion of the Chinese hamster FH06T1-1 cell line in a range of 2-10 times the activity of retinoic acid and retinol. In addition, most of the compound tested display antiproliferative activity comparable to that of natural retinoids. The reported data could be of interest for experimental anticancer therapy.

Geiparvarin analogues. 2. Synthesis and cytostatic activity of 5-(4-arylbutadienyl)-3(2H)-furanones and of N-substituted 3-(4-oxo-2-furanyl)-2-buten-2-yl carbamates.

In an attempt to determine some of the structural features of geiparvarin (1) that account for its cytostatic activity in vitro, a series of geiparvarin analogues (10a-i, 1, 12, and 14-16) which contain novel modifications in the region of the olefinic double bond and of the coumarin moiety have been designed and synthesized. Among the derivatives containing a carbamate moiety, only the analogues containing a carbamate group linked to an alkyl moiety 10b-i were endowed with potent cytostatic activity, whereas the corresponding benzene derivative 10a was devoid of any antiproliferative activity. 6-Methoxygeiparvarin 101 proved equally effective as geiparvin (1), while compounds containing an additional double bond at the side chain (12 and 14-16) were invariably 5-100-fold less effective than geiparvarin. Diene derivative 15, bearing a coumarin moiety, was essentially inactive against murine (L1210, FM3A) tumor cells but exhibited good activity against human (Molt/4F, MT-4) tumor cells.

Prolactin responses to haloperidol in normal young women.

The prolactin (PRL) responses to intramuscular haloperidol (HPD) (0.5, 1.0, and 1.5 mg) were evaluated in six normal premenopausal women during the follicular and luteal phases of their menstrual cycles. These were compared to the PRL responses to these doses of HPD in normal young men. PRL responses to HPD did not differ between the follicular and luteal phases. The mean log-transformed PRL response to the lowest HPD dose (0.5 mg) in women was less than that in the men, but the women had greater PRL responses than the men to the higher haloperidol doses (1.0 mg and 1.5 mg).

Imipramine in prepubertal major depressive disorders.

The potential effectiveness of imipramine hydrochloride (up to 5 mg/kg/d) was investigated in 53 prepubertal children suffering from major depressive disorder. Two complementary strategies were used simultaneously: a five-week, double-blind, placebo-controlled design (N = 38), and a plasma level/clinical response study (N = 30). Fifteen of the 16 children randomly assigned to active drug in the first study also participated in the second. Subjects were assessed using the Schedule for Affective Disorders and Schizophrenia for School Age Children and diagnosed according to unmodified Research Diagnostic Criteria. Response rates in the double-blind study were similar in both groups (imipramine, 56%; placebo, 68%). In the plasma level study, total maintenance plasma level (imipramine plus desipramine) was found to positively and linearly predict clinical response of the depressive syndrome (P less than .003). No evidence of a curvilinear relationship was found. Depressive hallucinations during the episode negatively predicted clinical response (P less than .05). Weight-corrected imipramine dosage did not predict either clinical response or plasma level in the individual subject. No predictors of response were found in the placebo group. These results suggest that the mean imipramine dosage was too low, and that future double-blind, placebo-controlled studies of imipramine in prepubertal major depression should include plasma level titration to above 150 ng/mL and an initial placebo washout period.

The assessment of affective disorders in children and adolescents by semistructured interview. Test-retest reliability of the schedule for affective disorders and schizophrenia for school-age children, present episode version.

The reliability of assessment of Research Diagnostic Criteria and DSM-III axis I affective disorders in children and adolescents was studied using a semistructured diagnostic interview. The Schedule for Affective Disorders and Schizophrenia (SADS) for School-Age Children (Kiddie SADS) Present Episode Version, an adaptation of the adult SADS for children was used. Fifty-two subjects, aged 6 through 17 years, were interviewed in a test-retest format by one of three pairs of interviewers. Assessment of symptoms and composite scales of the depressive syndrome were determined to have acceptable reliability, as were three depressive diagnoses. Conduct disorder was assessed with high reliability. Four anxiety disorders and their composite symptoms were assessed with unacceptable reliability; only separation anxiety was assessed with acceptable reliability. The results of this study showed generally lower reliability of symptoms, scales, and diagnoses than did two studies of adults using the SADS.

Growth hormone secretion in prepubertal children with major depression. I. Final report on response to insulin-induced hypoglycemia during a depressive episode.

Insulin tolerance tests (ITTs) were carried out on 46 drug-free prepubertal children with severe emotional disorders. Thirteen met unmodified Research Diagnostic Criteria for major depressive disorder, definite endogenous subtype, 17 met the criteria for nonendogenous major depressive disorder, and 16 fit DSM-III criteria for nondepressed neurotic disorders. The group with endogenous depression had significant hyposecretion of growth hormone (GH) in this test when compared with the other groups. Since GH hyposecretion in response to ITT has been found in most studies to be associated with endogenous major depression in adults, the data support the validity of the diagnosis of prepubertal endogenous major depressive disorder and the hypothesis of similarity or identity of prepubertal and adult major depressive disorders.

Growth hormone secretion in prepubertal children with major depression. III. Response to insulin-induced hypoglycemia after recovery from a depressive episode and in a drug-free state.

Insulin tolerance tests (ITTs) were performed after at least four months of sustained recovery from an episode of a major depressive disorder in 18 drug-free prepubertal children. Eleven had a definite endogenous subtype; seven did not. Sixteen children with nondepressed neurotic disorders made up a control group. The children with past endogenous depression continued to have significant hyposecretion of growth hormone (GH) in this test when compared with the other groups. Illness-recovery correlations were highly significant for the major depressive group as a whole. Paired comparisons of both depressive groups were not significantly different from illness to recovery. We conclude that prepubertal children with endogenous major depression continue to have hyposecretion of GH in response to ITTs in a recovered state and that this neuroendocrine marker is state independent. A GH hyporesponse to ITT may be a true marker of a past episode or of trait for endogenous major depressive disorder in prepuberty.

Growth hormone secretion in prepubertal children with major depression. II. Sleep-related plasma concentrations during a depressive episode.

Plasma growth hormone (GH) concentrations were determined every 20 minutes during sleep in 71 prepubertal children: 22 had endogenous major depressive disorder, 20 had nonendogenous major depressive disorder, 21 had nondepressed neurotic disorders, and eight were normal. Both depressive groups secreted significantly more GH during sleep than did controls. Measures included maximal GH plasma peak and area under the curve (AUC) during the total sleep period, during the first three hours after sleep onset, and during the first five hours after sleep onset. An AUC cutoff of 2,000 ng X min/mL identified positively half the prepubertal children with major depression; with a specificity of 78% (v neurotics) and 100% (v normal children). Increased GH secretion during sleep may be a marker of illness, a past episode, or trait for prepubertal major depression regardless of endogenicity.

Growth hormone secretion in prepubertal children with major depression. IV. Sleep-related plasma concentrations in a drug-free, fully recovered clinical state.

Prepubertal children with major depressive disorder have shown increased growth hormone (GH) secretion during sleep while in a depressive episode. When restudied in a fully recovered state (for at least three months) and drug free (for at least one month), their increased GH secretory pattern during sleep had not changed. Illness-recovery correlations using area under the curve for GH secretion during sleep were highly significant, whereas paired comparisons showed no significant differences. In addition, children who had recovered from major depressive episodes secreted significantly more GH during sleep than did nondepressed neurotic and normal children. No significant differences in delta-sleep were found in the depressed group between ill and recovered states nor among those who had recovered from major depressive episodes or controls. It is concluded that increased GH secretion during sleep is independent of depressive episodes, remains unaltered after full recovery, and may be a true marker of trait for major depressive disorder in prepuberty.

Sleep architecture and REM sleep measures in prepubertal major depressives. Studies during recovery from the depressive episode in a drug-free state.

The sleep of 28 fully recovered, drug-free, prepubertal patients with major depressive disorder was recorded for three consecutive nights in the laboratory. Recovered depressives had significantly shorter first rapid eye movement period (REMP) latencies and a higher number of REMPs compared with themselves when depressed and with nondepressed neurotic and normal children. In addition, most sleep continuity measures improved considerably on recovery. We suggest that a short first REMP latency may be a marker of past episode or of trait in prepubertal major depressives.

Psychotic symptoms in prepubertal major depressive disorder.

Symptoms of psychosis and psychoticlike phenomena were systematically inquired for, using a semistructured diagnostic interview protocol, in 58 prepubertal children who fulfilled Research Diagnostic Criteria for major depressive disorder. Subjects were classical into endogenous and nonendogenous subtypes. Forty-eight percent of the sample reported hallucinations. Thirty-six percent (including 48% of those in the endogenous subtype and 24% of those in the nonendogenous subtype) reported auditory hallucinations that consisted of one or more words other than their names, experienced in clear consciousness. Sixteen percent reported visual or tactile hallucinations. Four children were rated as having delusional ideas. Symptoms were analyzed in terms of contents, formal characteristics, thematic and temporal consistency with depressed mood, extent of the child's belief in the reality of the experience, frequency, and experienced location of auditory hallucinations. The psychopathologic meaning of the reported phenomena is uncertain.

Sleep architecture and REM sleep measures in prepubertal children with major depression: a controlled study.

We performed a three-night polysomnographic study of 54 rigorously assessed, drug free, prepubertal children who fit unmodified Research Diagnostic Criteria for major depressive disorder, and two groups of nondepressed controls (25 with emotional disorders and 11 who were normal). The groups did not differ polysomnographically, even though a high proportion of depressives and neurotics reported sleep disturbance in structured interviews. Sleep stage data do not appear to differentiate children with prepubertal major depressive disorders from nondepressed neurotic or normal children. Other psychobiologic findings in prepubertal depressives together with marked age effects on polysomnographic correlates of adult major depressive disorders suggest the hypothesis that polysomnographic abnormalities in adult major depressives are secondary to an interaction between depression and age.

Diurnal hormonal responses to thyrotropin-releasing hormone in normal men.

Bolus injections of synthetic thyrotropin-releasing hormone (TRH) were administered to five young normal men in the morning (0900 hr) and the evening (1800 hr) on different days. Frequent blood samples for prolactin (PRL) and TSH analyses were collected before and after TRH infusion. Although there were no differences between the morning and the evening basal PRL levels, a significantly greater PRL response to TRH in the evening was observed (delta PRL, a.m. vs p.m., p less than 0.025). Since TRH stimulates PRL through a direct effect on the pituitary, our data suggest that there is a diurnal variation in the pituitary lactotroph responsiveness to TRH. On the other hand, a.m. and p.m. basal and TRH-stimulated TSH responses were virtually identical.