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The relation between trait anxiety and the Harris MMPI PD subscales among psychiatric inpatients.

Investigated the relationship between trait anxiety and MMPI PD scores among psychiatric inpatients from a multidimensional standpoint by means of the Harris PD subscales. The trait anxiety scale of the State-Trait Anxiety Inventory and the Harris PD subscales were administered to 24 female and 21 male psychiatric inpatients. Trait anxiety was correlated positively with the basic PD scale in accord with previous findings. However, the Self-Alienation and Social Alienation PD subscales were the only Harris subscales that were correlated significantly with anxiety in the positive direction. The Social Imperturbability PD subscale was related inversely to trait anxiety. The findings were discussed primarily in terms of the potential benefit of employing the Harris subscales in studies of psychopathy and in clinical settings.

Adolescent↗

Ligand bite governs enantioselectivity: electronic and steric control in Pd-catalyzed allylic alkylations by modular fenchyl phosphinites (FENOPs).

Modular fenchyl phosphinites (FENOPs) containing different aryl units-phenyl (1), 2-anisyl (2), or 2-pyridyl (3)-are efficiently accessible from (-)-fenchone. For comparison of the influence of the different aryl units on enantioselectivities and reactivities, these FENOPs were employed in Pd-catalyzed allylic alkylations. The strongly chelating character of P,N-bidentate 3 is apparent from X-ray structures with PdCl2 ([Pd3Cl2]), and with allyl-Pd units in ([Pd3(eta1-allyl)] and [Pd3(eta3-allyl)]). FENOP3 gives rise to a PdL* catalyst of moderate enantioselectivity (42 % ee, R product). Surprisingly, higher enantioselectivities are found for the hemilabile, monodentate FENOPs 1 (83 % ee, S enantiomer) and 2 (69 % ee, S enantiomer). Only small amounts of 1 or 2 generate selective PdL* catalysts, while complete abolition of enantioselectivity appears with unselective PdL*2 species with higher FENOP concentrations in the cases of 1 or 2. Computational transition structure analyses reveal steric and electronic origins of enantioselectivities. The nucleophile is electronically guided trans to phosphorus. endo-Allyl arrangements are favored over exo-allyl orientations for 1 and 2 due to Pd-pi-pyridyl interactions with short "side-on" Pd-aryl interactions. More remote "edge-on" Pd-pi-aryl interactions in 3 with Pd-N(lp) coordination favor endo-allyl units slightly more and explain the switch of enantioselectivity from 1 (S) and 2 (S) to 3 (R).

Journal Article↗

Striatal dopa and glucose metabolism in PD patients with freezing of gait.

In Parkinson's disease (PD), freezing suggests sudden and transient blocks of motor behavior during initiating or continuous repetitive movements. Its underlying pathophysiology remains unclear. The objective of this study is to compare striatal dopamine metabolism and cerebral glucose metabolism between PD patients with and without freezing of gait (FOG). A total of 10 PD patients with FOG at off and 7 PD patients without FOG underwent brain positron emission tomography with (18)[F]-6-fluoro-levodopa (FDOPA) and (18)[F]-fluordesoxyglucose (FDG). Striatum decarboxylase activity was expressed by metabolic influx constants of the striatum related to the occipital lobe (Kocc). FDG uptake in caudate and putamen was normalized to global FDG uptake. Region of interest (ROI) analysis of striatal regions was used, as well as voxel-based analysis by statistical parametric mapping (SPM). ROI analysis did not reveal differences in striatal FDOPA and FDG uptake between the groups. SPM showed lower putaminal FDOPA uptake (P = 0.05 uncorrected) with increased FDG uptake (P = 0.01 uncorrected) in freezing PD, whereas caudate uptake of the two tracers was reduced. Freezing-related cortical FDG decrease was found in (right) parietal regions. In conclusion, in freezing PD, caudate uptake of FDG and FDOPA was reduced, whereas putamen FDOPA decrease was associated with FDG increase. Right hemisphere circuitry seemed to be more affected in freezing patients.

Blood Glucose↗

Structure and chromosomal localization of the human PD-1 gene (PDCD1).

A cDNA encoding mouse PD-1, a member of the immunoglobulin superfamily was previously isolated from apoptosis-induced cells by subtractive hybridization. To determine the structure and chromosomal location of the human PD-1 gene, we screened a human T cell cDNA library by mouse PD-1 probe and isolated a cDNA coding for the human PD-1 protein. The deduced amino acid sequence of human PD-1 was 60% identical to the mouse counterpart, and a putative tyrosine kinase-association motif was well conserved. The human PD-1 gene was mapped to 2q37.3 by chromosomal in situ hybridization.

Amino Acid Sequence↗

Synthesis and applications of poly(acryl p-aminobenzenesulfonamideamidine- p-aminobenzenesulfonylamide) chelating fiber for pre-concentrating and separating trace Bi(III), Hg(III), Au(III) and Pd(IV) from solution samples.

Poly(acryl p-aminobenzenesulfonamideamidine- p-aminobenzenesulfonylamide) chelating fiber containing "S", "N", and "O" elements was synthesized from polyacrylonitrile fiber and p-aminobenzene sulfonamide and used to enrich and separate trace Bi(III), Hg(III), Au(III), and Pd(IV) ions from wastewater and ore sample solution. The enrichment acidity, flow rate, elution conditions, reuse, interference ions, saturated adsorption capacity, constant of adsorption rate, analytical accuracy, and actual samples on chelating fiber were investigated by means of inductively coupled plasma optical emission spectrometry (ICP-OES) with satisfactory results. Solutions of 100 ng mL(-1) of Bi(III), Hg(III), Au(III), and Pd(IV) ions can be enriched quantitatively by this chelating fiber at a rate of 1.0 mL min(-1) at pH 4 and desorbed quantitatively with 20 mL of 0.25 M HCl and 2% CS(NH(2))(2) solution at 50 degrees C (with recovery >/=97%). When the chelating fiber was reused for 20 times, the recoveries of the analyzed ions enriched by the fiber were still over 95% (except for Hg(III)). One thousand-fold excesses of Mn(2+), Ca(2+), Zn(2+), Mg(2+), Fe(3+), Cu(2+), Ni(2+), Al(3+), and Ba(2+) ions and thousands-fold excesses of Na(+ )and K(+) cause little interference in the pre-concentration and determination of the analyzed ions. The saturated adsorption capacity of Bi(III), Hg(III), Au(III), and Pd(IV) was 4.850 x 10(-4), 3.235 x 10(-4), 2.807 x 10(-4), and 3.386 x 10(-4) mol g(-1), respectively. The constants of adsorption rate were 0.409 min(-1) for Bi, 0.122 min(-1) for Hg, 0.039 min(-1) for Au, and 0.080 min(-1 )for Pd. The relative standard deviations (RSDs) for the enrichment and determination of 10 ng mL(-1) Bi(III), Hg(III), Au(III), and Pd(IV) were lower than 2.3%. The results obtained for these ions in actual samples by this method were basically in agreement with the given values with average errors of less than 1.0%. FT-IR spectra shows that the existence of -SO(2)-Ar, -H(2)N-Ar, O=C-NH-, HN=C-NH-, and -HN-SO(2) functional groups are verified in the chelating fiber. From the FT-IR spectroscopy, we can see that Hg(III), Au(III), and Pd(IV) are mainly combined with nitrogen and sulfur (or oxygen), and Bi(III) is mainly combined with nitrogen (or oxygen) of the groups to form a chelating complex.

Journal Article↗

The D2 autoreceptor agonists SND 919 and PD 128483 decrease stereotypy in developing rats.

Although stereotyped behavior in adult rats is partly regulated by dopamine (DA) D2 autoreceptors, previous attempts to demonstrate D2 autoreceptor regulation of stereotypy in developing rats have been unsuccessful. In the present study, two highly selective D2 autoreceptor agonists were used to demonstrate D2 autoreceptor regulation of spontaneous stereotyped behavior in developing rats. Both SND 919 and PD 128483 produced significant dose-dependent decreases in the stereotypy counts of 21-day-old, 35-day-old, and adult rats. There was a 51% decrease in the stereotypy counts of 21-day-old rats injected with SND 919, 0.05 mg/kg, compared to a 36% decrease in the counts of rats pretreated with haloperidol. Similarly, PD 128483 significantly decreased the stereotypy counts of 21-, 35-day-old, and adult rats in a dose-dependent fashion. There was a 58% decrease in the stereotypy counts of 21-day-old rats injected with PD 128483, 0.1 mg/kg, compared to a 17% decrease in counts when the rats were first treated with haloperidol. The effect of haloperidol plus PD 128483 was significantly different from the effect of PD 128483 alone. Injection of SND 919 or PD 128483 had no significant effects on the stereotypy counts of 10-day-old rats. The results suggest that DA D2 autoreceptor-mediated regulation of spontaneous stereotyped behavior is functional at 21, but not 10, days of age.

Aging↗

The behavioural and neurochemical profile of the putative dopamine D3 receptor agonist, (+)-PD 128907, in the rat.

The functional relevance of the dopamine D3 receptor is still unresolved, largely because of the absence of selective D3 receptor ligands. In the present study we have examined the in vivo profile of (+)-PD 128907, a potent and functionally selective D3 receptor agonist. Low doses of (+)-PD 128907 reduced spontaneous locomotor activity in the rat (ED50 = 13 +/- 3 micrograms/kg, s.c.) a response which was comparable with the non-selective D2,3 receptor agonist apomorphine (ED50 = 13 +/- 1.6 micrograms/kg, s.c.). In addition (+)-PD 128907 impaired prepulse inhibition of the acoustic startle response, with significant effects observed at doses of 30 micrograms/kg when appropriate prepulse intensities were used. Higher doses reversed gamma-butyrolactone-induced catecholamine synthesis (ED50 = 95 +/- 22 and 207 +/- 37 micrograms/kg in accumbens and striatum respectively) and induced yawning (100-300 micrograms/kg), penile grooming (30-1000 micrograms/kg) and sniffing (> or = 300 micrograms/kg) although doses 3- to 10-fold greater than apomorphine were required to produce maximal effects. In contrast to apomorphine, however, (+)-PD 128907 failed to induce intense stereotyped licking and biting in the rat. In view of the potency and selectivity of (+)-PD 128907 for the D3 receptor, a role in the control of locomotor activity is suggested. In addition, the observation that (+)-PD 128907 disrupts prepulse inhibition, a phenomenon which is also impaired in schizophrenic subjects, may indicate the pathological importance of this receptor subtype.

4-Butyrolactone↗

Mechanistic studies of the phototoxic potential of PD 117596, a quinolone antibacterial compound.

PD 117596 is a novel quinolone compound that is being investigated for use as an antibacterial agent. Early investigations demonstrated a significant phototoxic liability associated with this compound. These studies were undertaken to investigate the mechanism of phototoxicity using an in vitro model. In the UVA region, PD 117596 was found to be a more efficient producer of singlet oxygen than rose bengal, ciprofloxacin, nalidixic acid, or PD 118879, another quinolone under investigation. The quantum yield of photoreaction for PD 117596 was relatively low (phi = 0.021); however, it was approximately 10-fold higher than other tested quinolones. In vitro studies using a mouse erythrocyte model were used to further investigate the mechanism of phototoxicity. PD 117596-induced photohemolysis was found to be oxygen dependent with a relatively rapid onset that progressed even after removal of light. Preirradiation of the compound prevented subsequent hemolytic or photohemolytic action. BHA, BHT, alpha-tocopherol, and the iron chelator DTPA were all found to be effective at ameliorating the photohemolytic response. The photohemolytic response was markedly enhanced when D2O was substituted for H2O in the incubation medium, indicating a singlet oxygen-mediated mechanism of action. A rise in thiobarbituric acid products was noted within 1 hr of irradiation and was maximal at the time of onset of overt photohemolysis. These data suggest that singlet oxygen production by irradiated PD 117596 is responsible for secondary changes in mouse red blood cells including lipid peroxidation and ultimately results in cellular lysis.

4-Quinolones↗

Cis-Dichloro(diaminosuccinate diethyl ester)palladium (II) as Pd(II)/Pt(II) model compound for DNA-binding and antitumor properties: solution equilibria of their aqua-, hydroxo-, and/or chloro-species.

Cis-Dichloro(diaminosuccinic acid)palladium(II), cis-[Pd(H2dasa)Cl2] (I), or cis-dichloro(diaminosuccinate diethyl ester)palladium(II), cis-[Pd(Et2dasa)Cl2] (II) reacts with two equivalents of AgClO4 to give insoluble Pd(dasa) or an aqueous solution of [Pd(Et2dasa) (H2O)2](ClO4)2, respectively. Three solutions of this salt were titrated with NaOH (I = NaClO4 (0.15M),37 degrees C), and 133 E(H+) data (3.5 < or = pH < or = 7) were treated by SUPERQUAD to fit log beta pqr of cis-aquahydroxo-(pqr = 10-1, -5.25(3)) and di-mu-hydroxo-species (20-2, -6.55(1)). At pH > 7 the ester hydrolysis prevents the calculation of log beta 10-2 for the cis-dihydroxo-complex. Another three solutions of such salt were titrated (I = 0.15M (NaClO4), 37 degrees C) with NaOH and NaCl simultaneously using two potentiometric systems (which measure H+ or Cl-). From 147 E(H+) and E(Cl-) data pairs and the above fixed log beta pqr, SUPERQUAD calculations yield log beta pqr for cis-chloro-aqua (pqr = 110, 3.65(1)), cis-chloro-hydroxo (11-1, -2.68 (4)), and cis-dichloro-species (120, 5.86(3)). Simulated and experimental titrations are in good agreement. Circular dichroism spectra of native DNA and drug:DNA complexes suggest that cis-Pd(H2dasa) and cis-Pd(Et2dasa) chelate moieties induce an opening and rotation of the stacked bases in the double helix. This finding is explained by the abundance of each one and of the total neutral and charged species of II in the tested CD solution.

Amino Acids, Diamino↗

PD-L1 is expressed by human renal tubular epithelial cells and suppresses T cell cytokine synthesis.

T cell activation is affected by both stimulatory and inhibitory co-signaling. MHC class II-expressing renal tubular epithelial cells (TEC) can function as APC for T cells. To study the influence of inhibitory ligands on TEC-mediated T cell activation, we examined the expression of programmed death ligand-1 (PD-L1) on human TEC line HK-2 cells, as well as in normal and diseased kidney samples. RT-PCR, FACS, and immunocytochemistry showed that PD-L1 is constitutively expressed on HK-2 cells, and is dramatically upregulated by IFN-gamma. In situ hybridization and immunohistochemical staining revealed constitutive low expression of PD-L1 on proximal tubules at both mRNA and protein levels in normal kidneys, but much higher expression in kidneys with type IV lupus nephritis. In vitro, pretreatment of IFN-gamma-stimulated HK-2 cells with anti-PD-L1 significantly enhanced IL-2 secretion from cocultured, mitogen-activated Jurkat or human peripheral blood T cells. These results suggest that the PD-L1:PD-1 pathway negatively regulates T cell activation by TEC, and may play an inhibitory role in TEC-mediated immune activation and immunopathology in the kidney.

Antigens, CD↗

PD-168077, a selective dopamine D4 receptor agonist, induces penile erection when injected into the paraventricular nucleus of male rats.

The effect of PD-168077 (N-methyl-4-(2-cyanophenyl)piperazynil-3-methylbenzamide maleate), a selective D4 dopamine receptor agonist, injected into the paraventricular nucleus of the hypothalamus on penile erection was studied in male rats. PD-168077 (1-200 ng) induced penile erection in a dose-dependent manner. The minimal effective dose was 50 ng, while the maximal response was found with 200 ng of the compound, which increased penile erection episodes from 0.3+/-0.03 to 1.7+/-0.21. The proerectile effect of PD-168077 was reduced almost completely by L-745,870 (3-(4-[chlorophenyl]piperazin-1-yl)-methyl-1H-pyrrolo[2,3-B]pyridine trihydrochloride), a selective D4 dopamine receptor antagonist, (1 microg) given into the paraventricular nucleus before the D4 dopamine agonist, and by other nonselective dopamine receptor antagonists, such as haloperidol (1 microg) and clozapine (1 microg), which block all dopamine receptor subtypes. The pro-erectile effect of PD-168077 was also reduced by the NO synthase inhibitor NG-nitro-L-arginine methylester (25 microg), but not by the oxytocin receptor antagonist d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg), when given into the paraventricular nucleus. In spite of its inability to prevent the pro-erectile effect of PD-168077 when given in the paraventricular nucleus, d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg) reduced almost completely PD-168077-induced penile erection when given into the lateral ventricles. The present results show that D4 dopamine receptors present in the paraventricular nucleus may influence penile erection by modulating the activity of paraventricular oxytocinergic neurons mediating erectile function.

Animals↗

Antioxidant capacity of G-6-PD-deficient erythrocytes.

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is the most common human enzymopathy. In this research, we studied two groups consisting of 30 male subjects who are G-6-PD deficient and 30 normal male subjects matched with the G-6-PD-deficient patients for age. All 30 assays were performed under normal conditions free of any oxidative attack that may result in haemolytic crisis in G-6-PD-deficient subjects. The erythrocyte glucose-6-phosphate dehydrogenase, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) activities, reduced glutathione (GSH) levels and erythrocyte and plasma thiobarbituric acid-reactive substances (TBARS) levels were measured. All parameters in each group did not differ significantly except for G-6-PD levels. These data show that G-6-PD-deficient subjects can survive in normal conditions unless they are exposed to any oxidative stress.

Antioxidants↗

Evaluation of PD 154075, a tachykinin NK1 receptor antagonist, in a rat model of postoperative pain.

PD 154075 ([(2-benzofuran)-CH2OCO]-(R)-alpha-MeTrp-(S)-NHCH(CH3) Ph) is a selective tachykinin NK1 receptor antagonist. Its effect on development and maintenance of thermal and mechanical hypersensitivity was examined in a rat model of surgical pain. When administered 30 min before surgery, PD 154075 dose-dependently (3-100 mg/kg, s.c.) prevented the development of thermal and mechanical hypersensitivity with respective minimum effective doses of 10 and 30 mg/kg. These antihypersensitivity effects lasted for 72 h. In contrast, the administration of PD 154075 (30 mg/kg, s.c.) after surgery had little or no effect on these nociceptive responses. PD 154075 antagonised thermal hypersensitivity induced by intrathecal administration of substance P, over the same dose range that blocked surgical hypersensitivity. However, it only partially blocked the thermal hypersensitivity induced by the selective NK2 receptor agonist [betaAla8]neurokinin A-(4-10). Morphine dose-dependently (1-6 mg/kg, s.c.) lengthened isoflurane and pentobarbitone-induced sleeping time in the rat. In contrast, PD 154075 (3-100 mg/kg, s.c.) did not interact with these anaesthetics. It is suggested that tachykinin NK1 receptor antagonists, such as PD 154075, may possess therapeutic potential as pre-emptive antihypersensitive agents.

Anesthetics↗

Hippocampal injury and neurobehavioral deficits are improved by PD 81,723 following hyperglycemic cerebral ischemia.

We investigated the effects of PD 81,723, an allosteric enhancer for the adenosine A(1) receptor subtype, on hippocampal injury and Morris water maze (MWM) performance following hyperglycemic cerebral ischemia and reperfusion (4-VO, 10 min) in the rat. PD 81,723 (3 or 10 mg/kg) or the equivalent volume of saline was administered intraperitoneally 30 min prior to ischemia. Moderate hyperglycemia was achieved by administration of D-glucose (3g/kg, i.p.) 15 min prior to induction of ischemia. Morris water maze trials were performed on the 6th, 7th, and 8th days after the ischemic insult. The rat brains were sectioned (8 microm), stained with cresyl violet/acid fuchsin, and evaluated for hippocampal ischemic injury by an experimenter blinded to the treatment conditions. At the higher dose, PD 81,723 (10 mg/kg) had no effect on hippocampal injury or MWM performance following hyperglycemic ischemia compared to corresponding saline-treated animals. In contrast, a lower dose of PD 81,723 (3 mg/kg) resulted in significant (P < 0.05, n = 8) reduction of hippocampal injury following hyperglycemic ischemia. Furthermore, corresponding Morris water maze performance (latency, learning index, and cumulative distance swum) was significantly improved by PD 81,723 (P < 0.05, n = 8). The results of the present study suggest that, in the presence of PD 81,723, an A(1) allosteric enhancer, endogenously produced adenosine is sufficient to exert significant neuroprotection during hyperglycemic ischemia. Moreover, the present study provides further evidence for a neuromodulatory role of adenosine during hyperglycemic ischemia.

Animals↗

Deep brain stimulation of the subthalamic nucleus in PD: an analysis of the exclusion causes.

OBJECTIVE: Deep Brain Stimulation (DBS) of the Subthalamic Nucleus (STN) represents a proper choice for the treatment of advanced Parkinson's disease (PD). A correct selection of the patients as candidates for the surgery is essential for a good outcome. In this study, we analyzed the exclusion causes of a series of PD patients hospitalized for the selection protocol. METHODS: Ninety-eight PD patients as potential candidates for the STN DBS were studied. All patients were hospitalized and underwent a clinical evaluation of the PD stage, a levodopa challenge, a MR of the brain and a neuropsychological assessment. RESULTS: The percentage of subjects considered not suitable for the surgery was 29.6%. A single cause of exclusion was present in 65.5% of not suitable patients, while multiple causes were present in 34.5%. The most frequent cause of exclusion was the finding of neuropsychological or psychic disorders (48.3%); in 37.9% of the patients, the motor disability was not severe enough to justify the surgery, while in 31%, we found relevant abnormalities at the brain MR. Three patients (10.3%) were poorly motivated for the surgery, while in three others (10.3%), we found a significant illness other than PD. CONCLUSIONS: The finding that about 30% of the PD patients potentially suitable for STN DBS presents some exclusion causes underlines the importance of a careful selection of the candidates for this surgery.

Age Factors↗

Complete amino-acid sequence of PD-S2, a new ribosome-inactivating protein from seeds of Phytolacca dioica L.

The primary structure has been determined for PD-S2, a new type 1 ribosome-inactivating protein (RIP), isolated from the seeds of Phytolacca dioica L. PD-S2 has 265 amino-acid residues, and a molecular mass of 29586 Da. The polypeptide chain contains four amino-acid residues more than PAP-S, a type-I RIP isolated from the seeds of the taxonomically related plant Phytolacca americana L. We have compared the amino-acid sequence of PD-S2 with those of two other RIPs with known three-dimensional structure: PAP-S and ricin A-chain (RTA), the active chain of the best known type-2 RIP. This analysis shows an identity of 76% and 33% with PAP-S and RTA respectively, and a similarity of 82% and 54%. Comparison with the PAP sequence, isolated from leaves of P. americana, shows an even higher identity (80%) and similarity (87%). Furthermore, the amino-acid residues reported in other RIPs to be invariant and participate in the definition of the active site (Tyr-76, Tyr-127, Glu-179, Arg-182 and Trp-211; PD-S2 numbering) are all present. Asn-74, Arg-138, Gln-175, and Glu-208 are also conserved, while Asn-209 is substituted by Glu, all residues located in the active-site cleft of RIPs (Tahirov, T.H., Lu, T.-H., Liaw, Y.-C., Chen, J.L. and Lin, J.Y. (1995) Crystal structure of abrin-a at 2.14 A, J. Mol. Biol. 250, 354-367). The polypeptide chain of PD-S2 contains two N-glycosylation sites at Asn-112 and Asn-120, the second of which appears to be linked to sugars. Like PAP-S, PD-S2 does not contain free sulfhydryl groups. The four cysteinyl residues of the two proteins have corresponding sequence positions, most likely with identical S-S pairing.

Amino Acid Sequence↗

Prevalence of G-6-PD deficiency in the Croatian Adriatic Coast population.

BACKGROUND: The objective of this study was to determine the prevalence of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency among the population of the Croatian Adriatic Coast, part of the Mediterranean basin. METHODS: The fluorescent spot test was used to screen 2,726 randomly selected high school students in the Croatian Adriatic coastal area. Fluorescence readings were performed at the beginning and at 3, 6, 10, and 25 min of incubation. Results were classified into the following three groups: bright fluorescence (BF), weak fluorescence (WF), and no fluorescence (NF). All NF and WF samples at 3 min were quantitatively measured using the spectrophotometric method. RESULTS: Twelve persons, 10 boys and 2 girls, were found to be deficient in G-6-PD, rendering a 0.44% prevalence of G-6-PD deficiency. All NF samples at fluorescent spot test were G-6-PD-deficient. WF at 3 min of the incubation period was present in 33 (1.2%) subjects, and only 2 (6%) were true positive. Fluorescence reading at 10 min of incubation omits five (41%) of the G-6-PD deficient samples. CONCLUSIONS: Prevalence of G-6-PD deficiency in the Croatian Adriatic coastal population is 0.44%. Fluorescent spot test for moderate enzyme deficiency is reliable in early fluorescence reading.

Adolescent↗

The discovery of PD 89211 and related compounds: selective dopamine D4 receptor antagonists.

The dopamine (DA) D2 family of receptors consists of the D2, D3, and D4 receptors. The DA D4 receptor is of interest as a target for drugs to treat schizophrenia based upon its high affinity for the atypical antipsychotic clozapine and its localization to the limbic and cortical regions of the brain. As part of a program to identify novel DA D4 receptor antagonists, a high-volume screen using the Parke-Davis compound library was initiated. This led to the discovery of PD 89211 (benzenemethanol, 2-chloro-4-[4-[(1H-benzimidazol-2-yl)methyl]-1-piperzinyl]) that displaced [3H]spiperone binding to hD4.2 with an affinity (Ki) of 3.7 nM. PD 89211 exhibited high selectivity for the DA D4.2 receptor (> 800-fold) as compared to other hDA receptor subtypes, rat brain serotonin, and adrenergic receptors. In vitro, PD 89211 had D4 receptor antagonist activity reversing quinpirole-induced [3H]thymidine uptake in CHOpro5 cells (IC50 = 2.1 nM). Limited structure-activity relationship (SAR) studies indicated that compounds with a 4-chloro-, 4-methyl-, and 3-chloro- substituents on the phenyl ring retained high affinity for D4 receptors, while those with a 4-methoxy- and no substituent had less affinity. While all clinically effective antipsychotics increase DA synthesis (DOPA accumulation) in rodents, PD 89211 did not increase DA synthesis in the DA-enriched striatum, indicating no effect on DA turnover and low propensity for exhibiting motor side effects. However, it did increase catecholamine synthesis in rat hippocampus, as did clozapine. Moreover, PD 89211 selectivity increased catecholamine synthesis in the hippocampus of wild type but not in mice lacking D4 receptors, suggesting that one function of D4 receptors may be to modulate DA/norepinephrine (NE) turnover in this brain area known to possess D4 receptors. The discovery of compounds like PD 89211 provides a tool to help in understanding the function of DA D4 receptors in the CNS.

Animals↗