New PMMA-Based Hydroxyapatite/ZnFe2O4/ZnO Composite with Antibacterial Performance and Low Toxicity

Polymethylmethacrylate (PMMA) is the most commonly used bone void filler in orthopedic surgery. However, the biocompatibility and radiopacity of PMMA are insufficient for such applications. In addition to insufficient biocompatibility, the microbial infection of medical implants is one of the frequent causes of failure in bone reconstruction. In the present work, the preparation of a novel PMMA-based hydroxyapatite/ZnFe2O4/ZnO composite with heterophase ZnFe2O4/ZnO NPs as an antimicrobial agent was described. ZnFe2O4/ZnO nanoparticles were produced using the electrical explosion of zinc and iron twisted wires in an oxygen-containing atmosphere. This simple, highly productive, and inexpensive nanoparticle fabrication approach could be readily adapted to different applications. From the findings, the presented composite material showed significant antibacterial activity (more than 99% reduction) against P. aeruginosa, S. aureus, and MRSA, and 100% antifungal activity against C. albicans, as a result of the combined use of both ZnO and ZnFe2O4. The composite showed excellent biocompatibility against the sensitive fibroblast cell line 3T3. The more-than-70% cell viability was observed after 1-3 days incubation of the sample. The developed composite material could be a potential material for the fabrication of 3D-printed implants.

Micron- and Nanosized Alloy Particles Made by Electric Explosion of W/Cu-Zn and W/Cu/Ni-Cr Intertwined Wires for 3D Extrusion Feedstock

A novel approach to electric explosion of intertwined wires to obtain homogeneous powder mixtures intended for preparing feedstock for extrusion 3D printing has been applied. The powder were composed of spherical micron- and nano-sized W/Cu particles in-situ alloyed by Zn and Ni during electric explosion of intertwined dissimilar metal wires is offered. The mean particle size measured by micron-sized particles was not more than 20 μm. The average number size of these particles was 3 μm and it was dependent on the energy input. The powders contained phases such as α-W, β-W/W₃O as well as FCC α-Cu(Zn) and α-Cu(Ni) solid solutions with the crystalline lattice parameters 3.629 and 3.61 A, respectively.

Synthesis of novel hierarchical micro/nanostructures AlOOH/AlFe and their application for As(V) removal

Hierarchical micro/nanostructured composites, which contain iron and/or its (hydr)oxides, demonstrate high rate and capacity of arsenic adsorption. The main objective of this paper is the use of novel low toxicity AlOOH/AlFe hierarchical micro/nanostructures for arsenic removal. AlOOH/AlFe composite was obtained by simple water oxidation in mild conditions using AlFe bimetallic nanopowder as a precursor. AlFe bimetallic nanopowder was produced by electrical explosive of two twisted wires in argon atmosphere. The productivity of the electrical explosion assembly was 50 g/h, with the consumption of the electrical energy was 75 kW·h/kg. AlFe bimetallic nanoparticles were chemically active and interacted with water at 60 °C. This nanocomposite AlOOH/AlFe is low cost and adsorbs more than 200 mg/g As(V) from its aqueous solution. AlOOH/AlFe composite has flower-like morphology and specific surface area 247.1 m²/g. The phase composition of nanostructures is present AlOOH boehmite and AlFe intermetallic compound. AlOOH/AlFe composite was not previously used for this. The flower-shape AlOOH morphology not only facilitated deliverability, but increased the As(V) sorption capacity by up to 200 mg/g. The adsorption kinetics has been found to be described by a pseudo-second-order equation of Lagergren and Weber-Morris models while the experimental adsorption isotherm is closest to the Freundlich model. This indicates the energy heterogeneity of the adsorbent surface and multilayer adsorption. The use of non-toxic nanostructures opens up new options to treat water affected by arsenic pollution.

Effect of Cold-Sintering Parameters on Structure, Density, and Topology of Fe-Cu Nanocomposites

The design of advanced nanostructured materials with predetermined physical properties requires knowledge of the relationship between these properties and the internal structure of the material at the nanoscale, as well as the dependence of the internal structure on the production (synthesis) parameters. This work is the first report of computer-aided analysis of high pressure consolidation (cold sintering) of bimetallic nanoparticles of two immiscible (Fe and Cu) metals using the embedded atom method (EAM). A detailed study of the effect of cold sintering parameters on the internal structure and properties of bulk Fe–Cu nanocomposites was conducted within the limitations of the numerical model. The variation of estimated density and bulk porosity as a function of Fe-to-Cu ratio and consolidation pressure was found in good agreement with the experimental data. For the first time, topological analysis using Minkowski functionals was applied to characterize the internal structure of a bimetallic nanocomposite. The dependence of topological invariants on input processing parameters was described for various components and structural phases. The model presented allows formalizing the relationship between the internal structure and properties of the studied nanocomposites. Based on the obtained topological invariants and Hadwiger’s theorem we propose a new tool for computer-aided design of bimetallic Fe–Cu nanocomposites.

Hierarchical γ-alumina: From Pure Phase to Nanocomposites

Recent advances in nanotechnology make it possible to create nanomaterials based on γ-alumina with novel hierarchical structure and physicochemical properties. Hierarchical γ-alumina can be synthesized using chemical or physical methods. The nanostructures based on γ-alumina exhibit unique properties, which are utilized in the design of efficient applications. These superior properties are often due to their hierarchical organizations from the nanosize scale to the macroscopic level. The present review is devoted to the contemporary state of the studies on the methods to produce hierarchical γ-alumina. We tried to summarize herein the literature data on the methods of synthesis of hierarchical γ-AlOOH and γ-Al2O3 with controlled morphology and the application of these methods for the synthesis of hierarchical γ-AlOOH and γ-Al2O3 nanocomposites.

Assessing long-term neuroinflammatory responses to encephalopathy using MRI approaches in a rat endotoxemia model

Sepsis-associated encephalopathy (SAE) induces neuroinflammation, which is associated with cognitive impairment (CI). CI is also correlated with aging. We used contrast-enhanced magnetic resonance imaging (MRI), perfusion MRI, and MR spectroscopy to assess long-term alterations in BBB permeability, microvascularity, and metabolism, respectively, in a rat lipopolysaccharide-induced SAE model. Free radical-targeted molecular MRI was used to detect brain radical levels at 24 h and 1 week post-LPS injection. CE-MRI showed increased Gd-DTPA uptake in LPS rat brains at 24 h in cerebral cortex, hippocampus, thalamus, and perirhinal cortex regions. Increased MRI signal intensities were observed in LPS rat brains in cerebral cortex, perirhinal cortex, and hippocampus regions 1 week post-LPS. Long-term BBB dysfunction was detected in the cerebral cortex at 6 weeks post-LPS. Increased relative cerebral blood flow (rCBF) in cortex and thalamus regions at 24 h, decreased cortical and hippocampal rCBF at 6 weeks, decreased cortical rCBF at 3 and 12 weeks, and increased thalamus rCBF at 6 weeks post-LPS, were detected. MRS indicated that LPS-exposed rat brains had decreased: NAA/Cho metabolite ratios at 1, 3, 6, and 12 weeks; Cr/Cho at 1, 3, and 12 weeks; and Myo-Ins/Cho at 1, 3, and 6 weeks post-LPS. Free radical imaging detected increased radical levels in LPS rat brains at 24 h and 1 week post-LPS. LPS-exposed rats were compared to saline-treated controls. We clearly demonstrated BBB dysfunction, impaired vascularity, and decreased brain metabolites, as measures of long-term neuroinflammatory indicators, as well as increased free radicals in a LPS-induced rat SAE model.

Purinergic signaling modulates human visceral adipose inflammatory responses: implications in metabolically unhealthy obesity

Obesity is accompanied by chronic inflammation of VAT, which promotes metabolic changes, and purinergic signaling has a key role in a wide range of inflammatory diseases. Therefore, we addressed whether fat inflammation could be differentially modulated by this signaling pathway in the MUO and in individuals who remain MHO. Our results show that the necrotized VAT of both groups released greater levels of ATP compared with lean donors. Interestingly, MUO tissue SVCs showed up-regulation and engagement of the purinergic P2X7R. The extracellular ATP concentration is regulated by an enzymatic process, in which CD39 converts ATP and ADP into AMP, and CD73 converts AMP into adenosine. In VAT, the CD73 ectoenzyme was widely distributed in immune and nonimmune cells, whereas CD39 expression was restricted to immune CD45PAN⁺ SVCs. Although the MUO group expressed the highest levels of both ectoenzymes, no difference in ATP hydrolysis capacity was found between the groups. As expected, MUO exhibited the highest NLRP3 inflammasome expression and IL-1β production. MUO SVCs also displayed up-regulation of the A2AR, allowing extracellular adenosine to increase IL-1β local secretion. Additionally, we demonstrate that metabolic parameters and BMI are positively correlated with purinergic components in VAT. These findings indicate that purinergic signaling is a novel mechanism involved in the chronic inflammation of VAT underlying the metabolic changes in obesity. Finally, our study reveals a proinflammatory role for adenosine in sustaining IL-1β production in this tissue.

Investigation of differences between nanosecond electropulse and electrohydraulic methods of lithotripsy: a comparative in vitro study of efficacy

PURPOSE

To compare the effectiveness of novel nanosecond electropulse lithotripsy with standard electrohydraulic lithotripsy to demonstrate and authenticate their differences because both modalities appear to be similar.

MATERIALS AND METHODS

An in vitro fragmentation study was conducted using cuboid BegoStone phantoms, which mimic hard and soft stones, based on an established model. Three different stone sizes were used in the testing having volumes of 100, 256, and 320 mm(3). A nanosecond electropulse lithotripter (NEPL) and an electrohydraulic lithotripter (EHL) were operated using a range of probe sizes at comparable energy settings and pulse rates with the objective of obtaining a stone fragment <2 mm. To compare the efficacy of these two lithotripters, the number of pulses needed for stone phantom fragmentation was recorded according to probe size and energy setting, which were then converted into units of cumulative energy.

RESULTS

The results clearly demonstrated that, for all operating modes and stone phantom types, the NEPL device needs much less cumulative energy and thus fewer pulses and consequently less time to achieve stone fragmentation than the EHL device. The disparity in the results is explained by the dissimilar mechanisms at work in the compared lithotripters during destruction of the stone. The electropulse stone disintegration mechanism transfers energy directly into the stone because of discharge penetration into a solid body. This contrasts with the electrohydraulic mechanism in EHL in which energy is transferred through the liquid medium, which also creates a damaging shockwave.

CONCLUSIONS

The findings demonstrate that, for all operating modes and stone types, the NEPL device needs much less cumulative energy and thus fewer pulses for stone fragmentation than the EHL device. The disparity in the results is explained by the dissimilar mechanisms at work in the compared lithotripters during destruction of the stone.

Retrograde endoscopic lithotripsy using the innovative nanosecond electropulse method

PURPOSE

The purpose of this clinical study is to assess the safety and efficiency of a novel lithotripsy method for endoscopic treatment of urinary stones throughout the urinary tract via semi-rigid and flexible endoscopes. This new method is based on the transfer of nanosecond high voltage electric pulses to the stones through flexible probes of various sizes.

METHODS

The study involved 879 patients aged 19-88 with renal, ureter and bladder calculi. Gender distribution: 46.3% female and 53.7% male. The prospective single-arm study took place at three centers. The goal of the clinical study was to evaluate the safety and efficacy of a novel lithotripsy method. All treatments were performed retrograde transurethrally. A variety of probes were used for stone fragmentation at different locations. Auxiliary treatments and adverse events were recorded as per protocol. Statistical analysis was conducted using SPSS software.

RESULTS

Nanosecond electropulse lithotripsy (NEPL) was found to be technically feasible for all patients with stones located in the kidney, UPJ, ureter and bladder. It requires only a few dozen pulses to disintegrate stones while causing only minor stone migration. The overall stone-free rate in the study was 96%. The average time required for executing the entire procedure was 45±28 min. The overwhelming majority of intraoperative complications occurred due to endoscopic manipulation when using a rigid ureterorenoscope and not due to lithotripsy impact.

CONCLUSIONS

NEPL is a new, efficient and safe method for urinary stone disintegration that can be used throughout the urinary tract using rigid and flexible endoscopes. Intraoperative complications of the NEPL procedure do not exceed the percentage of adverse effects observed in other lithotripsy methods. The main advantages of relatively low-cost NEPL are fast stone fragmentation requiring only a few dozen pulses to disintegrate stones, tissue safety and availability of highly flexible probes for treating stones in the lower pole through a flexible ureterorenoscope.

Enzyme-linked-immunosorbent-assay for the detection of a novel 21-kda protein associated with the clinical course of patients with urogenital tumors

A novel 21 kDa protein (p21) was detected in sera of patients with urogenital tumors by ELISA, using rabbit polyclonal antibodies generated against the p21 polypeptide. Eight out of 11 patients (72%) exhibited a 2-5 fold increase in pre-treatment p21 serum levels as compared with 20 healthy individuals. A decrease of p21 levels was observed in 6 out of 8 patients in which a regression of the disease was shown post-treatment. An increase or no change in p21 levels was observed in 3 patients with no change or progression of the disease. The ELISA described herein may be useful for clinical monitoring of patients with urogenital tumors, some of which have no available tumor marker.

Marihuana: Tetrahydrocannabinol and Related Compounds

Marihuana was analyzed for its major constituents, cannabidiolic acid, cannabidiol, tetrahydrocanabinol, and cannabinol, by treating the petroleum ether extract with diazomethane. The methyl esters so produced, together with the unchanged components, were subjected to gas chromatography on a polar silicone column.

Comparative study of MBR and activated sludge in the treatment of paper mill wastewater

The study was based on a full scale activated sludge plant (AS) compared to a parallel operated pilot membrane bioreactor (MBR) with flat sheets membranes. Both systems received their influent from an anaerobic bioreactor treating paper mill wastewater. MBR produced an effluent of much better quality than AS in terms of suspended solids, containing 1 mg/L or less in 80% of the monitoring time, while the AS effluent contained 12 mg/L. This could save the necessity of further treatment by filtration in the case of MBR. Other effluent quality parameters, such as organic matter (COD and BOD), phosphorus and ammonia nitrogen, did not indicate substantial differences between AS and MBR. Calcium carbonate scaling and formation of a bacterial layer on the membrane caused severe flux reduction. The membrane blockage because of scaling and biofouling proved to be very serious, therefore, it required proper and more complicated maintenance than the AS system. This study leads to the conclusion that in the case of paper mill wastewater, after anaerobic biotreatment, if there is no need for excellent effluent quality in terms of suspended solids, the replacement of the AS by the MBR would not be strongly justified, mainly because of maintenance cost.

Worldwide trends in alcohol and drug impaired driving

Improved laws, enhanced enforcement, and public awareness brought about by citizens' concern, during the 1980s led to dramatic declines in drinking and driving in the industrialized world. The declines included about 50% in Great Britain, 28% in The Netherlands, 28% in Canada, 32% in Australia, 39% in France, 37% in Germany, and 26% in the United States. Some of these declines may be due in part to lifestyle changes, demographic shifts, and economic conditions. In most countries the declines reversed in the early 1990s and drinking and driving began to increase. By the middle of that decade the increases stabilized and the rates of drinking and driving again began to decline. These decreases were much less dramatic than those in the 1980s. Approaching the end of the 1990s and early in the new century, the record has been mixed. Some countries (France and Germany (until 2002)) continued to reduce drinking and driving while in other countries (Canada, the Netherlands, Great Britain, and the United States), there was stagnation and in some cases small increases or even large increase as was the case in Sweden. Complacency and attention to other issues in recent years have been difficult to overcome in some countries. Harmonization of traffic safety laws in the European Union has strengthened laws in some countries but threatens existing strong policies in others. It may be that the major gains have already been made and that additional progress will require a much greater level of scientific knowledge, use of new and emerging technologies, and political and social commitment to put in place proven countermeasures.

Cecal volvulus: a report of two cases occurring after the antegrade colonic enema procedure

BACKGROUND

Many children with chronic constipation and fecal incontinence have benefited from the antegrade colonic enema (ACE) procedure. Routine antegrade colonic lavage often allows such children to avoid daytime soiling. This report describes 2 children in whom the ACE procedure was complicated by a cecal volvulus.

METHODS

A retrospective review of 164 children with an ACE procedure was conducted. Two instances of cecal volvulus were identified.

RESULTS

The first child presented with abdominal pain and difficulty intubating the ACE site. Over the subsequent day, his pain worsened, and radiographs depicted a colonic obstruction. At laparotomy, a cecal volvulus resulting in bowel necrosis was observed, and resection of the affected bowel and appendix (in the right lower quadrant) and end ileostomy was required. He subsequently had the stoma closed and a new ACE constructed with a colon flap. The second child presented with shock and evidence of an acute abdomen. At laparotomy, a cecal volvulus was noted, and ileocolic resection including the ACE stoma (located at the umbilicus) and an ileostomy and Hartmann pouch was performed. He had a protracted hospital course requiring ventilator and inotropic support. He currently is well and still has an ileostomy stoma.

CONCLUSIONS

A high index of suspicion for a potentially life-threatening cecal volvulus should be maintained in children undergoing an ACE procedure who present with abdominal pain, evidence of bowel obstruction, or difficulty in advancing the ACE irrigation catheter.

The use of a laboratory school protocol to evaluate concepts about efficacy and side effects of new formulations of stimulant medications

Recently, new long-acting formulations of racemic methylphenidate (MPH: Ritalin LA, Metadate CD and Concerta) and amphetamine (AMP: Adderall XR) were developed and are now approved by the Food and Drug Administration (FDA). In addition, dexmethylphenidate (Focalin), the pharmacologically active d-threo enantiomer of MPH, also was approved by the FDA. In the initial phases of development, prototypes of these five new formulations were evaluated using the University of California, Irvine (UCI) Laboratory School Protocol (LSP), in which surrogate measures of efficacy are collected in highly controlled settings rather than clinical measures of effectiveness in the less-controlled, natural environments of home or school. The LSP studies were followed by large effectiveness and safety studies required for gaining FDA approval. These initial efficacy and side effect studies in the LSP provided missing information about the basic pharmacokinetic (PK) and pharmacodynamic (PD) properties of MPH and AMP and produced some new discoveries (i.e., acute tolerance) that were used to help design the final products. The final once-a-day formulations used different drug delivery systems to achieve long-acting efficacy (Ritalin LA, Metadate CD, Concerta, Adderall XR). All four drug delivery systems were based on two processes: first, a bolus delivery (BD) process to achieve rapid onset of efficacy (mg), and second, a controlled delivery (CD) process to achieve rates of delivery (mg/hr) or a delayed bolus (mg) to maintain efficacy. A theoretical approach was used to compare and contrast the new once-a day formulations of MPH by selecting total daily doses (mg/d) that would equate drug delivery by the first process (mg of the initial bolus) and the second process (mg/hr over specified time period). In addition to efficacy, applications of the LSP to measure common side effects related to eating and sleeping were described and discussed.

Stimulation of protein kinase C pathway mediates endocytosis of human nongastric H+-K+-ATPase, ATP1AL1

The human nongastric H+-K+-ATPase, ATP1AL1, shown to reabsorb K+ in exchange for H+ or Na+, is localized in the luminal plasma membrane of renal epithelial cells. It is presumed that renal H+-K+-ATPases can be regulated by endocytosis. However, little is known about the molecular mechanisms that control plasma membrane expression of renal H+-K+-ATPases. In our study, activation of protein kinase C (PKC) using phorbol esters (phorbol 12-myristate 13-acetate) leads to clathrin-dependent internalization and intracellular accumulation of the ion pump in stably transfected Madin-Darby canine kidney cells. Functional inactivation of the H+-K+-ATPase by PKC activation is shown by intracellular pH measurements. Proton extrusion capacity of ATP1AL1-transfected cells is drastically reduced after phorbol 12-myristate 13-acetate incubation and can be prevented with the PKC blocker bisindolylmaleimide. Ion pump internalization and inactivation are specifically mediated by the PKC pathway, whereas activation of the protein kinase A pathway has no influence. Our results show that the nongastric H+-K+-ATPase is a specific target for the PKC pathway. Therefore, PKC-mediated phosphorylation is a potential regulatory mechanism for apical nongastric H+-K+-ATPase plasma membrane expression.

Mind-body health at 25: an assessment

This is a personal assessment of the past 25 years of the mind-body health movement. It argues that, despite many advances, the movement is notably marred by its unwillingness to confront the economic and environmental determinants of health.

Placebo-controlled, blinded comparison of antenatal betamethasone on mouse liver development

The objective of this investigation was to evaluate, in a placebo-controlled manner, the developing mouse liver after antenatal exposure either to a single dose or to a multidose of betamethasone. Ninety gravid CD-1 mice were randomly divided into three groups (n = 30/group) to receive either saline (0.25 mL s.c.) or betamethasone (0.10 mg s.c.) as a single dose on gestational day (GD) 14 of a 19-day gestation or as a 0.10 mg dose given twice daily on GD 14 and on GD 15 (4 doses). GD 0 is defined by the presence of a copulatory plug. These exposures of betamethasone cause fetal mouse lung maturation as would be observed in premature humans at 24-34 weeks of gestation. The livers were removed either from the fetuses on GD 16.5 or from the offspring on postnatal day 1, 3, 5, and 120. Special stains were used to evaluate hepatocyte architecture, glycoprotein and glycogen content, extramedullary hematopoiesis and iron storage. Hepatocyte intranuclear DNA content, cell size, and cell shape were measured by image analysis (CAS 200). At GD 16.5, betamethasone produced a significant decrease in the liver/body weight ratio that, when compared with the placebo group, was greater with the multidose (p < 0.01) than with the single dose (p < 0.05). 16.5 GD single dose hepatocytes were smaller in size as compared to placebo without impact on intranuclear DNA (p < 0.01). Single dose PND 1 hepatocytes demonstrated an increase in intranuclear DNA as compared to placebo but without change in cell size (p < 0.001). The prenatal reduced liver weight recovered in the newborn period. No difference in microscopic architecture of the hepatocytes or histologic differences between either of the three treatment groups was found in glycogen deposition, extramedullary hematopoiesis or iron metabolism at GD 16.5 and postnatally. It was concluded antenatal betamethasone can cause a decrease in the liver/body weight ratio in the fetal mouse that recovers eventually without any functional impact as assessed histologically.

Olanzapine-induced leukopenia with human leukocyte antigen profiling

Olanzapine is an atypical antipsychotic medication frequently used in the management of psychotic states. While it has proved to be safe compared to clozapine with regard to haematotoxicity, because it has only been available for a few years, full documentation of its haematological side-effects remains incomplete. We report a case of olanzapine-induced leukopenia with associated neutropenia. Since clozapine-induced haematotoxicity has been associated with characteristic human leukocyte antigen (HLA) groups, HLA typing was determined in this patient. Following failure with typical antipsychotic medication, the patient received 10 mg/day of olanzapine. Three weeks later, he developed fever and a significant decrease in leukocyte count. Olanzapine was immediately discontinued. HLA typing was determined. The white cell count returned to normal and the fever, most probably secondary to the low white cell count, subsided with antibiotic treatment. HLA typing results were: A1 24, B7, B35, DRB1*15, DRB1*11, DRB3*01-03, DRB5*01-02. Olanzapine may induce serious leukopenia and neutropenia. HLA typing in this single patient demonstrated a distinct haplotype compared to that previously observed in clozapine-induced haematoxicity.

Homologs of the yeast Sec complex subunits Sec62p and Sec63p are abundant proteins in dog pancreas microsomes

Cotranslational protein transport into dog pancreas microsomes involves the Sec61p complex plus a luminal heat shock protein 70. Posttranslational protein transport into the yeast endoplasmic reticulum (ER) involves the so-called Sec complex in the membrane, comprising a similar Sec61p subcomplex, the putative signal peptide receptor subcomplex, and the heat shock protein 40-type subunit, Sec63p, plus a luminal heat shock protein 70. Recently, human homologs of yeast proteins Sec62p and Sec63p were discovered. Here we determined the concentrations of these two membrane proteins in dog pancreas microsomes and observed that the canine homologs of yeast proteins Sec62p and Sec63p are abundant proteins, present in almost equimolar concentrations as compared with Sec61alphap monomers. Furthermore, we detected fractions of these two proteins in association with each other as well as with the Sec61p complex. The J domain of the human Sec63p was shown to interact with immunoglobulin heavy chain binding protein. Thus, the membrane of the mammalian ER contains components, known from the posttranslationally operating protein translocase in yeast. We suggest that these components are required for efficient cotranslational protein transport into the mammalian ER as well as for other transport processes.

Assembly of heterodimeric luciferase after de novo synthesis of subunits in rabbit reticulocyte lysate involves hsc70 and hsp40 at a post-translational stage

Heterodimeric luciferase from Vibrio harveyi had been established as a unique model enzyme for direct measurements of the effects of molecular chaperones and folding catalysts on protein folding and subunit assembly after de novo synthesis of subunits in rabbit reticulocyte lysate. It was observed that luciferase assembly can be separated in time from synthesis of the two subunits and that under these post-translational conditions assembly was inhibited by either ATP depletion or inhibition of peptidylprolyl cis/trans isomerases, that is, by addition of cyclosporin A or FK506. Furthermore, it was observed that the inhibitory effect of FK506 on luciferase assembly can be suppressed by addition of purified cyclophilin, thereby providing the first direct evidence for the involvement of peptidylprolyl cis/trans isomerases in protein biogenesis in the eukaryotic cytosol. Here the ATP requirement in luciferase assembly has been characterized. Depletion of either Hsp90 or CCT from reticulocyte lysate did not interfere with luciferase assembly. However, addition of purified Hsc70 stimulated luciferase assembly. While addition of purified Hsp40 did not have any effect on luciferase assembly, the stimulatory effect of Hsc70 was further increased by Hsp40. Thus, after synthesis of the two subunits in reticulocyte lysate assembly of heterodimeric luciferase involves Hsc70 and its co-chaperone Hsp40. Therefore, Hsc70 aids protein biogenesis in the eukaryotic cytosol not only at the levels of nascent polypeptide chains and precursor proteins that have to be kept competent for transport into cell organelles, but also at the level of subunits that have to be kept competent for assembly.

Evaluation of individual subjects in the analog classroom setting: II. Effects of dose of amphetamine (Adderall)

Multiple dependent variables were graphed for 29 subjects who participated in a double-blind evaluation of 4 doses of Adderall, plus positive (methylphenidate) and placebo control conditions. Five judges ranked the conditions for each subject, and analyses of individual subjects indicated that these rankings were concordant (reliable) across judges. Consensus rankings were assigned to each subject, and an analysis of these ranks showed that the conditions differed significantly. The choice of best conditions were judged to be across 3 doses of Adderall (10, 15, and 20 mg). This confirms the clinical impression of individual differences in optimal dose of stimulant medication. The methodological, graphical, and statistical methods presented in this article provide a systematic, reliable procedure for evaluating relative response of individuals to different doses of stimulant medication.

Evaluation of individual subjects in the analog classroom setting: I. Examples of graphical and statistical procedures for within-subject ranking of responses to different delivery patterns of methylphenidate

In this article, we describe graphical and statistical methods developed to evaluate the response patterns of individual children with attention deficit hyperactivity disorder (ADHD) to different conditions of treatment with stimulant medication. We used data from an investigation of drug delivery patterns to demonstrate these methods. Thirty-one children with ADHD participated in a double-blind crossover study of four conditions (three patterns of delivery of methylphenidate and a placebo control). In each condition, the children were evaluated across an 11-hour (7:00 a.m. to 6:00 p.m.) laboratory school day, and ratings of classroom behavior were obtained at regular intervals across the day. Graphical procedures were developed to display, for each individual, time courses of multiple measures of behavior taken across each double-blind test day. Expert clinicians judged these graphs and used this information to rank-order the test days from best to worst. A within-subject variant of Kendall's W was used to evaluate, for each subject, whether the rankings of these multidimensional graphs were reliable (concordant) across judges. A generalized kappa statistic was used to evaluate, for each condition, the reliability of the judges' rankings across subjects. Friedman's analysis of variance of ranks was used to evaluate, for the study, whether the conditions differed in terms of the average (consensus) rank assigned by the judges.

Assessment and intervention for attention-deficit/hyperactivity disorder in the schools. Lessons from the MTA study

The MTA experience provides several lessons that may have clinical relevance. First, the MTA study identified six key instruments (see Table 1) that clinicians may want to use, but even on these instruments discrepancies in parent and teacher sources should be expected. We believe that unnoticed or unresolved discrepancies may be important factors contributing to the "disconnect" identified by the Consensus Conference Panel. Based on the MTA experience, we recommend a telephone call to the child's teacher, specifically to inquire about any discrepancy in the "source by domain" summary, as an efficient way to make a meaningful connection "... between developmental or educational (school-based) assessments and health-related (medical practice-based) services" for children with ADHD. Second, evaluation of pharmacologic intervention in the MTA study confirmed that teachers' reports are crucial for documenting efficacy, whereas parent reports are crucial for documenting side effects. Based on the MTA experience, we recommend frequent telephone contact with the teacher specifically to inquire about the peak effects and dissipation of effects of medication that are expected to occur during the school hours as a way to improve "... communication between diagnosticians and those who implement and monitor treatment in the schools."

Acute tolerance to methylphenidate in the treatment of attention deficit hyperactivity disorder in children

OBJECTIVES

To evaluate the efficacy of several drug delivery patterns of methylphenidate and to determine whether acute tolerance develops to this widely used stimulant medication in the treatment of children with attention deficit hyperactivity disorder.

METHODS

Double-blind trials were conducted in a laboratory school setting in which multiple measures of efficacy were obtained frequently in the morning and afternoon across the school day. In study I, relative efficacy was determined for three dosing patterns of methylphenidate: a standard twice-daily profile, a flat profile, and an ascending profile. In study II, tolerance was assessed by comparison of three-times-a-day regimens in which the time of the middle dose varied.

RESULTS

In study I, the efficacy of the ascending treatment increased across the day, and in the afternoon it was equal to the efficacy of the twice-daily treatment, indicating that an initial bolus was not required for efficacy. The efficacy of the flat treatment declined across the day, and in the afternoon it was significantly less than in the twice-daily treatment, suggesting that tolerance may be developing. In study II, acute improvements in efficacy were reduced to the second of two closely spaced but not to two widely spaced bolus doses, suggesting that shortly after exposure to high concentrations, efficacy is reduced to given concentrations of methylphenidate. In a concentration-effect model, a tolerance term was needed to account for counterclockwise hysteresis.

CONCLUSIONS

Acute tolerance to methylphenidate appears to exist. This should be considered in the design of an optimal dosing regimen for the treatment of children with attention deficit hyperactivity disorder.

A complementary perspective to primary socialization theory

Primary socialization theory as formulated by Oetting and his associates emphasizes the transmission of societal norms during childhood and adolescence within society's three major socializing agencies: family, school, and small, intimate peer groups. The norms thus transmitted may be prosocial or deviant, with prosocial norms more likely to be transmitted through strong bonds to healthy families or schools. Personality traits and other personal characteristics influence negative outcomes, such as deviance or drug use, only to the extent that they interfere with socialization to family or school. Our own research does not address primary socialization theory directly in that we have not focused on the transmission of norms per se as central. Nevertheless, we have studied social factors, personality factors, and various psychopathologies as etiological for deviance and substance use. By and large our research has supported the hypotheses of primary socialization theory, even extending them in specific areas, such as the importance of family influences as etiological. Our work has also emphasized the significance of rebelliousness and impulse control in this regard. Like all large-scale theories which necessarily abstract from the totality and diversity of human behavior, primary socialization theory leaves some gaps requiring further elucidation. Among these is its ethnocentric and temporocentric perspective, but even within this perspective it understates the difficulties for adolescents in making a successful transition to adult social roles (Kingley Davis) and in establishing a unique identity independent of parents (Erik H. Erikson). Also, it generally ignores the salience of the youth culture as rebellious against the older generation, a particularly important characteristic of modern society. And finally, it should cover the process of "maturing out" of deviance, which perhaps results in a reaffirmation of the legitimacy of norms transmitted earlier, and it should also cover gender differences in their transmission and legitimization. Nevertheless, despite these caveats and especially because of this theory's insightfulness and path-breaking character, its hypotheses should be tested in carefully designed, large-scale studies. These studies should allow, among other factors, measurement of the effects of genetic factors on the early emergence of deviant personality attributes and of their impact on the transmission of prosocial norms. [Translations are provided in the International Abstracts Section of this issue.]

Experimental cross-validation of DSM-IV types of attention-deficit/hyperactivity disorder

OBJECTIVE

To examine the discriminant validity of DSM-IV attention-deficit/hyperactivity disorder (ADHD) types by testing the hypothesis that types are associated with specific kinds of functional impairment and to compare overlap of DSM-IV and DSM-III-R ADHD.

METHOD

Consecutive referrals (n = 692) to a pediatric subspecialty clinic for ADHD were classified into 1 of each of the 3 DSM-IV types of ADHD using parent and teacher checklist ratings of ADHD symptoms. The resulting types were compared on clinical correlates and on whether the children also met criteria for DSM-III-R ADHD.

RESULTS

The validity of DSM-IV types was supported by dimension-specific impairment and other distinct correlates. Academic problems aggregated in the 2 types defined by extreme inattention, and externalizing problems aggregated in the 2 types defined by extreme hyperactivity.

CONCLUSION

DSM-IV appeared superior to DSM-III-R in subcategorical homogeneity and in exhaustiveness (ability to classify all apparent cases).

Objective and subjective measures of the pharmacodynamic effects of Adderall in the treatment of children with ADHD in a controlled laboratory classroom setting

In a randomized double-blind crossover study of children with attention deficit hyperactivity disorder (ADHD), the time course effects of four doses of Adderall (5, 10, 15, and 20 mg) and an inactive (placebo) control, and an active (Ritalin) control were evaluated. A laboratory classroom setting was established in which subjective (teacher ratings of deportment and attention) and objective (scores on math tests) measurements were taken every 1.5 hours across the day. In addition to significant time and dose effects of Adderall, significant time-of-day effects were documented in the placebo condition for the subjective measure of deportment and objective measures of performance. Regression analyses were used to estimate the magnitude of these baseline effects. Correlations across time were used to evaluate the test-retest reliability of each measure in the face of these time-dependent placebo effects. After placebo/time adjustments, within-subject correlations between pairs of measures were used to evaluate the validity of the math test as a measure of response to stimulant medication.

Analog classroom assessment of Adderall in children with ADHD

OBJECTIVE

This was a randomized, double-blind, crossover study of 30 children with attention-deficit/hyperactivity disorder (ADHD) that evaluated the time course effects of four doses of Adderall (5, 10, 15, and 20 mg), an inactive control (placebo), and a positive control (clinical dose of methylphenidate).

METHOD

For each treatment condition, a capsule was administered in the morning and assessments were performed in an analog classroom setting every 1.5 hours across the day. Subjective (teacher ratings of deportment and attention) and objective (scores on math tests) measures were obtained for each classroom session, and these measures were used to evaluate time-response and dose response effects of Adderall.

RESULTS

For doses of Adderall greater than 5 mg, significant time course effects were observed. Rapid improvements on teacher ratings and math performance were observed by 1.5 hours after administration, and these effects dissipated by the end of the day. The specific pattern of time course effects depended on dose: the time of peak effects and the duration of action increased with dose of Adderall.

CONCLUSIONS

This documentation of efficacy in a controlled study supports the addition of Adderall to the armamentarium of psychotropic medications for the treatment of ADHD. The differences in time-response patterns of Adderall and methylphenidate may help tailor treatment to meet specific clinical needs of different children with ADHD.

Association of the dopamine receptor D4 (DRD4) gene with a refined phenotype of attention deficit hyperactivity disorder (ADHD): a family-based approach

Previously in this journal, we reported an association of the dopamine D4 receptor gene (DRD4) and attention deficit hyperactivity disorder (ADHD). In a population-association (case-control) study of 39 children with a refined phenotype of ADHD and 39 ethnically matched controls, we observed an increased percentage of the 7 repeat allele (29% vs 12%) and the 7+ genotype (49% vs 21%) in the ADHD group compared to the control group. In a replication and an extension of our initial study, we recruited another sample of ADHD subjects and found percentages of the 7 repeat allele (28%) and the 7+ genotype (48%) consistent with our previous findings. We used a family-based approach to evaluate a predicted association of DRD4 and ADHD based on a test of allele transmission focused on the 7 repeat allele. We identified 52 families based on the diagnosis of the refined phenotype of ADHD in the proband and the availability of DNA from both biological parents as well as the proband. Haplotype relative risk (HRR) analysis was performed to test our a priori hypothesis and produced significant results (chi-square = 4.65, P < 0.035). This provides additional evidence that the DRD4 gene is associated with a refined phenotype of ADHD.

Persistent pulmonary hypertension of the newborn (PPHN) treated with inhaled nitric oxide: preliminary hearing outcomes

The hearing of 28 children, born with a diagnosis of persistent pulmonary hypertension of the newborn (PPHN) and treated with inhaled nitric oxide, was followed. The latest test for the children varied from 5 to 30 months. Of this group, three children had mild conductive hearing losses; no child had a significant sensorineural hearing loss.

In vivo spin trapping of nitric oxide generated in the small intestine, liver, and kidney during the development of endotoxemia: a time-course study

Spin trapping of nitric oxide (NO.) in vivo in liver, small intestine, kidney, and plasma of intact rats was accomplished using diethyldithiocarbamate (DETC) administered intraperitoneally. DETC combines with Fe2+ to form (DETC)2-Fe and is an excellent trapping agent for nitric oxide. DETC distribution and uptake by the organs of interest was determined and the formation of the active trapping agent (DETC)2-Fe was assayed in the various organs and plasma. The capacity of this spin trap to capture NO. in vivo was demonstrated by administering sodium nitroprusside to the animals. The trapping procedure was then used to assess the course of NO. generation during a 6 h period in animals that had been treated with endotoxin. The rate of NO. generation/gram tissue was determined during the last 15 min of each time period. The results indicate that induction of nitric oxide generation begins earliest in the small intestine, then in the liver, and still later in the kidney and plasma. Nitric oxide production was most intense in the liver and was still increasing at the end of the experiment. Control animals receiving the spin trapping agent showed only little or no evidence of nitric oxide production except for the small intestine. The results show that induction of NO. generation caused by endotoxin begins at different times in different organs.

Cytotoxic effects by microinjection of ADP-ribosylated skeletal muscle G-actin in PtK2 cells in the absence of Clostridium perfringens iota toxin

The ADP-ribosylating toxins Clostridium botulinum C2 toxin and C. perfringens iota toxin, which ADP-ribosylate monomeric G-actin at Arg-177 but not the polymeric F-actin, induce depolymerization of the actin cytoskeleton in cultured cells. Since ADP-ribosylated G-actin has properties of a barbed-end-capping protein, we studied whether the ADP-ribosylated actin affects the actin cytoskeleton of PtK2 cells even in the absence of ADP-ribosylating toxin. Skeletal muscle actin was ADP-ribosylated by C. perfringens iota toxin and the toxin was removed using an anti-iota toxin antibody. Microinjection of ADP-ribosylated actin caused retraction of the cell body, redistribution and depolymerization of the actin cytoskeleton in a concentration- and time-dependent manner. The finding that ADP-ribosylated actin affects per se the actin cytoskeleton explains the cytopathic effects of ADP-ribosylating toxins on microfilaments, although F-actin is not directly modified by the toxins.

Perceptions of social pathology in the neighborhood and the etiology of narcotic addiction. A retrospective study

In this study, we examined whether differential perceptions of poor urban neighborhoods may contribute to narcotic addiction in individuals who grow up in these neighborhoods. Three groups of adult males provided retrospective perceptions of the neighborhoods where they lived at ages 12 to 14. The groups, matched on neighborhood, age, and race, were: narcotic addicts, peer controls--a never-addicted control sample of age-11 associates of the addicts, and community controls--a never-addicted control sample of age-11 peers who did not associate with the addicts. Results suggested clear group differences in perceptions of neighborhood deviance, with addicts perceiving the greatest and community controls the least amount of deviance. However, within groups, subjects who lived in more socially deviant areas, as determined by official records, tended to view their neighborhoods as more deviant than did subjects who lived in less deviant neighborhoods.

Changes in locus-of-control attitudes about drug misuse in a self-help group in a methadone maintenance clinic

Clients of a methadone-maintenance clinic in Brooklyn, New York participating in a clinically-guided self-help (CGSH) program plus standard treatment (methadone maintenance plus individual counseling) demonstrated statistically significant changes in locus-of-control beliefs, from external to internal causation, about personal responsibility for drug misuse. Members of two control groups--one participating in a didactic lecture program plus standard treatment and the other receiving only standard treatment--failed to demonstrate similar changes. This increase in internal locus of control in the CGSH group suggests the potential efficacy of CGSH as a relapse-prevention therapeutic technique.