'Immigrant paid caregivers' and primary caregivers' burden.
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Aged↗
Biomedical subjects
E Rosa
Publications and source records attributed to E Rosa.
Effects of intact glucosinolates and products produced from glucosinolates in myrosinase-catalyzed hydrolysis on the potato cyst nematode (Globodera rostochiensis Cv. Woll).
The potato cyst nematode (Globodera rostochiensis cv. Woll) is responsible for large yield losses in the potato crop, and opportunities for reducing the attack of these plant nematode species are, therefore, important. This study has been devoted to the testing of the in vitro effects on the potato cyst nematode of eight glucosinolates [prop-2-enyl-, but-3-enyl-, (R)-4-methylsulfinylbut-3-enyl-, benzyl-, phenethyl-, 4-hydroxybenzyl-, (2S)-2-hydroxybut-3-enyl-, and (2R)-2-hydroxy-2-phenylethylglucosinolate] as well as the effects of the products of this myrosinase-catalyzed hydrolysis. The glucosinolates were used at three concentrations, 0.05, 0.3, and 1.0 mg/mL, in the presence or absence of the enzyme myrosinase. The effects of the compounds on the mortality were monitored every 8 h for a 72 h period. No effects were found for any of the intact glucosinolates. However, when active myrosinase was included with 1 mg/mL phenethylglucosinolate at pH 6.5, 100% mortality was observed within just 16 h. A similar effect was achieved at the same concentration of benzyl- and prop-2-enylglucosinolates in the myrosinase-containing solutions, although longer exposures were required (24 and 40 h, respectively). The main aglucone products released from the glucosinolates with pronounced effects on the nematodes were shown to be the corresponding isothiocyanates. The results suggest that mixtures of these specific glucosinolates and active myrosinase or autolysis of plant materials containing these enzymes and glucosinolates might be used to control the potato cyst nematode in the soil.
Animals↗
[Translaryngeal tracheostomy using the Fantoni technique: report of 104 cases].
OBJECTIVE: Surgical tracheostomy morbidity led the authors to investigate new election techniques. The aim of this retrospective study was to assess the translaryngeal tracheostomy (TLT), complications and cost. METHODS: From January 1998 to January 2001, 104 patients were treated with TLT modified: 69 males (66.3%) and 35 females (33.7%), average age 52.6 +/- 9.5 years. The original pathologies were: traumatical (36), neurological (37), surgical (9), heart (4), respiratory (18). The average time between intubation and execution of TLT was 4.2 +/- 1.3 days. RESULTS: Fifty four patients died (52%) and 50 patients lived (48%). Two complications (1.9%) occurred in those who survived: a breaking of the guidewire in traction. Extraction of the tracheostomy tube by clamp, a haemorrhage in 2nd post-operative day due to a thyroid vessel lesion. The haemostasis was performed by classical tracheostomy. The average number of days to decannulation was 25 +/- 1 days. CONCLUSIONS: TLT reduces trauma or trachea and neighbouring structures. This technique is safe and easy. TLT is an effective method, in non-urgent situations, in children and adults, as well as in brachytypes and the obese.
Adolescent↗
Experimental real-time phase synchronization of a paced chaotic plasma discharge.
Experimental phase synchronization of chaos in a plasma discharge is studied using a phase variable lift technique (i.e., phase points separated by 2pi are not considered as the same). Real-time observation of synchronized and unsynchronized states is made possible through a real-time sampling procedure. Parameter space regions of synchronization and unsynchronization are identified, and a set of equations is suggested to model the real plasma circuit.
Journal Article↗
Exploiting the natural redundancy of chaotic signals in communication systems
Chaotic signals can be used as carriers of information in communication systems. In this work we describe a simple encoding method that allows one to map any desired bit sequence into a chaotic waveform. The redundancy of the resulting information carrying signal enables us to devise a novel signal reconstruction technique that is able to recover relatively large parts of the chaotic signal starting from just a few samples of it. We show that this technique allows one to increase both the transmission reliability and the transmission rate of a communication system even in the presence of noise.
Journal Article↗
Binding and preliminary evaluation of 5-hydroxy- and 10-hydroxy-2,3, 12,12a-tetrahydro-1H-[1]benzoxepino[2,3,4-ij]isoquinolines as dopamine receptor ligands.
The N-methyl, N-ethyl, and N-n-propyl derivatives of 5-hydoxy- and 10-hydroxy-2,3,12,12a-tetrahydro-1H-[1]benzoxepino[2,3, 4-ij]isoquinolines were prepared as monophenolic ligands for the dopamine receptor and evaluated for their affinity at D(1)-like and D(2)-like subtypes. All compounds showed very low D(1) affinities. This could be ascribed to the absence of a catechol nucleus or of the beta-phenyldopamine pharmacophore. Only the N-methyl-5-hydroxy- (5a), N-methyl-10-hydroxy- (6a), and N-methyl-4-bromo-10-methoxy-2,3, 12,12a-tetrahydro-1H-[1]benzoxepino[2,3,4-ij]isoquinolines (26a) bound the D(2) receptors with low affinity, in the same range as dopamine. In compounds 5a and 6a, the 2-(3-hydroxyphenyl)ethylamine moiety does not meet the requirements of the D(2) agonist pharmacophore: namely, the 2-(3-hydroxyphenyl)ethylamine does not reach the trans, fully extended conformation. The three compounds did not interact with recombinant human D(4) receptors, and only 5a showed low affinity for rat recombinant D(3) receptors. Analysis of the influence of Na(+) on [(3)H]spiperone binding showed that 5a displays a potential dopamine D(2) agonist profile, whereas 6a probably has a dopamine D(2) antagonist activity. The D(2) agonist activity of 5a was proved by the effects on prolactin release from primary cultures of rat anterior pituitary cells.
Animals↗
Cardiovascular effects of ketanserin on normotensive rats in vivo and in vitro.
In this work, we report for first time that: (1) low doses of ketanserin (0.2 mg/kg) produce a transient hypotensive response in anaesthetized rats, which is basically due to the blockade of 5-hydroxytryptamine (2A) (5-HT)2A receptors, whereas high doses (1 mg/kg) of ketanserin cause a sustained hypotension also mediated by the blockage of alpha1-adrenergic receptors; (2) the in vitro vasorelaxant action of high concentrations of ketanserin (>10 microM) involves Ca2+ antagonism, which may also be responsible, at least in part, for the inhibition of high-K+-induced 45Ca2+ uptake, the inhibition of Ca2+-induced contractions in initially Ca2+-free high-K+ medium, and the negative chronotropic effects on isolated atria. This Ca2+ antagonistic activity does not seem to contribute to the in vivo cardiovascular effects of ketanserin at therapeutic doses.
Animals↗
Triazene drug metabolites. Part 17: Synthesis and plasma hydrolysis of acyloxymethyl carbamate derivatives of antitumour triazenes.
A series of 3-acyloxymethyloxycarbonyl-1-aryl-3-methyltriazenes 5 was synthesised by the sequential reaction of 1-aryl-3-methyltriazenes with (i) chloromethyl chloroformate, (ii) NaI in dry acetone, and (iii) either the silver carboxylate or the carboxylic acids in the presence of silver carbonate. The hydrolysis of these compounds was studied in pH 7.7 isotonic phosphate buffer and in human plasma. Triazene acyloxycarbamates demonstrated their ability to act as substrates for plasma enzymes. For compound 5f, a pH-rate profile was obtained which showed the hydrolysis to involve acid-base catalysis. The reaction is also buffer catalysed. Thus, at pH 7.7, pH-independent, base-catalysed and buffer-catalysed processes all contribute to the hydrolysis reaction. The sensitivity of the hydrolysis reaction to various structural parameters in the substrates indicates that hydrolysis occurs at the ester rather than the carbamate functionality. In plasma, the rates of hydrolysis correlate with partition coefficients, the most lipophilic compounds being the most stable. An aspirin derivative suffers two consecutive enzymatic reactions, the scission of the aspirin acetyl group being followed by the scission of the acyloxy ester group. These results indicate that triazene acyloxymethyl carbamates are prodrugs of the antitumour monomethyltriazenes. They combine chemical stability with a rapid enzymatic hydrolysis, and are consequently good candidates for further prodrug development. Moreover, this type of derivative allowed the synthesis of mutual prodrugs, associating the antitumour monomethyltriazenes with anti-inflammatory NSAIDs as well as with the anticancer agent butyric acid.
Antineoplastic Agents↗
Communication through chaotic modeling of languages.
We propose a communication technique that uses modeling of language in the encoding-decoding process of message transmission. A temporal partition (time-delay coarse graining of the phase space based on the symbol sequence statistics) is introduced with little if any intervention required for the targeting of the trajectory. Message transmission is performed by means of codeword, i.e., specific targeting instructions are sent to the receiver rather than the explicit message. This approach yields (i) error correction availability for transmission in the presence of noise or dropouts, (ii) transmission in a compressed format, (iii) a high level of security against undesirable detection, and (iv) language recognition.
Artificial Intelligence↗
Integrated chaotic communication scheme
We present the characteristics and an analysis of a proposed communication scheme fully based on chaos theory. The key point is that the proposed scheme introduces the dynamical system as a way to encode and decode information and as a signal wave generator. In this scheme, all the protocols used to communicate digitally are fully integrated into one single design based on a chaotic modulation process. The chaotic encoder finds a set of trajectories that codes the information into a hard to decode chaotic wave form that carries a large amount of information. We also show how our scheme can handle multiplexing, which is also used as a way to enhance security, and its ability to handle noise.
Journal Article↗
Repetition and form priming interact with neighborhood density at a brief stimulus onset asynchrony.
The relationships between repetition- and form-priming effects and neighborhood density were analyzed in two masked priming experiments with the lexical decision task. Given that form-priming effects appear to be influenced by a word's orthographic neighborhood, it is theoretically important to find out whether repetition priming also differs as a function of the word's orthographic neighborhood. Within an activation framework, repetition- and form-priming effects are just quantitatively different phenomena, whereas the two effects are qualitatively different in a serial-ordered model of lexical access (the entry-opening model). The results show that repetition- and form-priming effects were stronger for hermit words than for words with many neighbors. These results pose some problems for both activation and serial-ordered models. The implications of these results for determining how neighbors affect the identification of a word are discussed.
Adult↗
Immigration and health: the Italian National Focal Point experience.
This report is a description of the situation of migrant populations in Italy. It was written by a committed team of experts from public institutions, non-governmental organisations (NGO) and volunteer associations that for three years have been part of the Italian National Focal Point (NFP) within the European Project "AIDS & Mobility", which is being co-ordinated by the Netherlands Institute for Health Promotion and Disease Prevention (the Netherlands) and financed by the European Commission DG/V. This year the Italian National Focal Point, co-ordinated by the Telefono Verde AIDS of the Istituto Superiore di Sanità, has produced a second report (the first one was published in 1998) on health issues related to migrant populations. Besides providing an updated picture on the presence of foreigners in Italy, such report illustrates the present legislative situation within the sanitary area and some interventions regarding prevention, treatment and rehabilitation provided by each structure in the Italian NFP to foreign citizens. The initiatives carried out during the year 1999 by public institutions, NGO and volunteer associations are also reported in order to detect the psycho-social-sanitary needs of immigrants and target prevention programmes to their particular and specific needs.
Acquired Immunodeficiency Syndrome↗
Conformationally constrained butyrophenones with mixed dopaminergic (D(2)) and serotoninergic (5-HT(2A), 5-HT(2C)) affinities: synthesis, pharmacology, 3D-QSAR, and molecular modeling of (aminoalkyl)benzo- and -thienocycloalkanones as putative atypical antipsychotics.
A series of novel conformationally restricted butyrophenones (2-(aminoethyl)- and 3-(aminomethyl)thieno- or benzocycloalkanones bearing (6-fluorobenzisoxazolyl)piperidine, (p-fluorobenzoyl)piperidine, (o-methoxyphenyl)piperazine, or linear butyrophenone fragments) were prepared and evaluated as atypical antipsychotic agents by in vitro assays of affinity for dopamine receptors (D(1), D(2)) and serotonin receptors (5-HT(2A), 5-HT(2C)) and by in vivo assays of antipsychotic potential and the risk of inducing extrapyramidal side effects. Potency and selectivity depended mainly on the amine fragment connected to the cycloalkanone structure. As a group, compounds with a benzisoxazolyl fragment had the highest 5-HT(2A) activities, followed by the benzoylpiperidine derivatives; in general, alpha-substituted cycloalkanone derivatives were more active than the corresponding beta-substituted congeners. CoMFA (comparative molecular field analysis) and docking studies showed electrostatic, steric, and lipophilic determinants of 5-HT(2A) and D(2) affinities and 5-HT(2A)/D(2) selectivity. The in vitro and in vivo pharmacological profiles of N-[(4-oxo-4H-5, 6-dihydrocyclopenta[b]thiophene-5-yl)ethyl]-4-(6-fluorobenzisox azol-3 -yl)piperidine (23b, QF 0510B), N-[(4-oxo-4,5,6, 7-tetrahydrobenzo[b]thiophene-5-yl)ethyl]-4-(6-fluorobenzisoxazol- 3-y l)piperidine (24b, QF 0610B), and N-[(7-oxo-4,5,6, 7-tetrahydrobenzo[b]thiophene-6-yl)ethyl]-4-(6-fluorobenzisoxazol- 3-y l)piperidine (29b, QF 0902B) suggest that they may be effective antipsychotic drugs with low propensity to induce extrapyramidal side effects.
Animals↗
Targeted cleavage of RNA molecules by human RNase P using minimized external guide sequences.
The endoribonuclease RNase P processes tRNA-like structures that are assembled out of two separate strands. In these bimolecular constructs, one of the strands is cleaved by the enzyme, and the other one is called the external guide sequence (EGS). A number of EGS with different mutations and deletions were tested for the ability to induce cleavage with human RNase P. Different domains of the original tRNAtyr-like structure were deleted or modified. The anticodon stem and loop and the variable loop could be deleted without a detrimental effect on recognition by RNase P. Modifications in the lengths of T stem and aminoacyl acceptor stem led to a decrease in the relative amount of cleavage, whereas modifications of the D stem were more permissible. Single nucleotide deletions in the T loop reduced cleavage to different extents, depending on the position. Values for the Kd of complex formation of bimolecular constructs with annealing arms of varying lengths ranged from 0.2 nM to 28 nM. A cleavage rate of 1 min(-1) was measured for both the bimolecular target-EGS complex and tRNA precursor.
Anticodon↗
A close look at therapeutic touch.
CONTEXT: Therapeutic Touch (TT) is a widely used nursing practice rooted in mysticism but alleged to have a scientific basis. Practitioners of TT claim to treat many medical conditions by using their hands to manipulate a "human energy field" perceptible above the patient's skin. OBJECTIVE: To investigate whether TT practitioners can actually perceive a "human energy field." DESIGN: Twenty-one practitioners with TT experience for from 1 to 27 years were tested under blinded conditions to determine whether they could correctly identify which of their hands was closest to the investigator's hand. Placement of the investigator's hand was determined by flipping a coin. Fourteen practitioners were tested 10 times each, and 7 practitioners were tested 20 times each. MAIN OUTCOME MEASURE: Practitioners of TT were asked to state whether the investigator's unseen hand hovered above their right hand or their left hand. To show the validity of TT theory, the practitioners should have been able to locate the investigator's hand 100% of the time. A score of 50% would be expected through chance alone. RESULTS: Practitioners of TT identified the correct hand in only 123 (44%) of 280 trials, which is close to what would be expected for random chance. There was no significant correlation between the practitioner's score and length of experience (r=0.23). The statistical power of this experiment was sufficient to conclude that if TT practitioners could reliably detect a human energy field, the study would have demonstrated this. CONCLUSIONS: Twenty-one experienced TT practitioners were unable to detect the investigator's "energy field." Their failure to substantiate TT's most fundamental claim is unrefuted evidence that the claims of TT are groundless and that further professional use is unjustified.
Humans↗
Short oligonucleotides as external guide sequences for site-specific cleavage of RNA molecules with human RNase P.
Human RNase P recognizes a small model substrate consisting of only the 5' leader sequence, aminoacyl acceptor stem, and T stem and loop of a tRNA precursor. It was demonstrated here that a bimolecular construct in which the T loop is opened between G57 and A58 (tRNA numbering system) is still processed by RNase P. The strand that is cleaved can be considered the target RNA, whereas the other strand serves as an external guide sequence (EGS). The nucleotides corresponding to nt 58-60 in the T loop could be deleted without affecting cleavage of the substrate. Thus, the complete T loop can be replaced by the single-stranded sequence UUCG or UUCA (nt 55-57 in the T loop). The four nucleotides UUCR possibly form a structure that resembles the uridine turn in the T loop of tRNA. Because recognition by RNase P is independent of the helical sequence, this motif can be used for targeting RNA molecules for EGS-directed cleavage by human RNase P. Chemically modified EGSs with 2'-O-methyl groups also showed activity in inducing RNase P cleavage. Several 13-mer EGSs targeted to the 2.1-kb surface antigen mRNA of hepatitis B virus (HBV) were designed and tested using a co-transcriptional cleavage assay with a 2.1-kb HBV transcript. Some of the new EGSs were capable of inducing cleavage of the HBV RNA by RNase P.
Base Sequence↗
Triazene drug metabolites: part 15. Synthesis and plasma hydrolysis of anticancer triazenes containing amino acid carriers.
PURPOSE: The synthesis of chemically stable triazene prodrugs capable of hydrolysing under physiological conditions to liberate cytotoxic monomethyltriazene alkylating agents. METHODS: A series of 3-aminoacyl-1-aryl-3-methyltriazenes was synthesised through reaction of 1-aryl-3-methyltriazenes with N-BOC protected amino acids using the DCC method of activation, followed by deprotection of the amino function using HCl in nitromethane. Half-lives for the hydrolysis of these compounds to the corresponding monomethyltriazenes at 37 degrees C in isotonic phosphate buffer and in 80% human plasma containing 20% phosphate buffer were determined by HPLC. RESULTS: The aminoacyltriazene prodrugs hydrolyse in isotonic phosphate buffer with t1/2 values ranging from 26 to 619 minutes. In human plasma, several decompose at the same rate as in phosphate buffer whereas those containing more lipophilic groups decompose more slowly. A beta-alanyl derivative was found to be more stable in phosphate buffer (t1/2 = 180 minutes) than in plasma (t1/2 = 53 minutes). An N-acetylated alpha-alanyl derivative was found to be chemically stable in phosphate buffer (t1/2 = 10 hours) but liberated the cytotoxic drug in t1/2 = 41 minutes in plasma, demonstrating its ability to act as a substrate for plasma enzymes. CONCLUSIONS: Aminoacyltriazenes are prodrugs of the antitumour monomethyltriazenes hydrolysing in human plasma with a range of reactivities. The acylation of the alpha-amino group seems to be an effective and simple means of reducing the chemical reactivity of the alpha-aminoacyl derivatives while retaining a rapid rate of enzymatic hydrolysis.
Amino Acids↗
Design of short external guide sequences (EGSs) for cleavage of target molecules with RNase P.
The minimal substrate for human RNase P consists of the 5' leader sequence, aminoacyl acceptor stem, T-stem and T-loop of tRNA. The sequences corresponding to the D-stem, anticodon stem and loop and variable loop are replaced by a bulge which can be as small as 1 nt, but requires > 4 nt for optimal cleavage by RNase P. We found that a trans construct in which the T loop is opened between G57 and A58 (tRNA numbering system) is still processed by RNase P. The strand that is cleaved can be considered the target RNA while the other strand serves as an External Guide Sequence (EGS). We were also able to delete the nucleotides corresponding to nt 58 to 60 in the T-loop without affecting cleavage of the substrate. We propose that the sequence UUCG or UUCA (nucleotide 55 to 57 in the T-loop) positioned 3' to a double helical region of 12 to 13 basepairs containing a bulge of > 4 nt can form a structure that is recognized by human RNase P. The four nucleotides UUCR probably form a structure that resembles the uridine turn in the Tloop of tRNA. Since recognition by RNase P seems to be independent of the helical sequence, we suggest that this motif can be used for targeting RNA molecules for EGS-directed cleavage by RNase P. Based on these results, several 13-mer EGSs targeted to the 2.1 Kb surface antigen mRNA of hepatitis B virus (HBV) were designed and tested using a co-transcriptional cleavage assay with a 2.1 Kb HBV transcript. Some of these were capable of inducing cleavage of the HBV RNA by RNase P. The use of such small EGSs for the inactivation of various genes will be discussed.
Base Sequence↗