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This study investigates the racial-mathematical identity profiles of Black American adolescents. Survey data were collected in five schools across one U.S. urban school district at two time points (spring 2018 [n = 197] and spring 2019 [n = 210]). Based on extant research regarding psychological response patterns to racialized school stress, we investigated the existence of an identity negotiation pattern in which students were motivated to resist negative stereotypes about Black people by achieving well in mathematics. We conducted a latent profile analysis combining students' self-beliefs across five indicators: racial centrality, racial public regard, mathematics attainment value, mathematics mastery experiences, and resistance motivation. Three distinct racial-mathematical identity profiles emerged: (1) Mathematics Devalued/Ambivalent, (2) Moderately Math Attained, and (3) Resistors. We found associations between profile membership and students' gender, negative math emotions, and their receipt of cultural and critical mathematics instruction. We also found an association between the identity profiles and school type (academically selective "magnet" schools vs. open-enrollment neighborhood schools), but not in the direction that might be assumed. Moreover, we found that certain school environment factors (i.e., racial stereotyping and cultural and critical mathematics instruction) were significantly different in racially diverse magnet schools than in the neighborhood schools. Overall, our data reveal the existence of a highly motivated Resistor profile among Black students, that is predicted by cultural and critical mathematics instruction but underrepresented within this district's selective magnet schools., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

This study presents the results of the effectiveness of 13 therapeutic diets for autism spectrum disorder from 818 participants of a national survey, including benefits, adverse effects, and symptom improvements. The average Overall Benefit of diets was 2.36 (0 = no benefit, 4 = great benefit), which was substantially higher than for nutraceuticals (1.59/4.0) and psychiatric/seizure medications (1.39/4.0), p < 0.001. The average Overall Adverse Effects of diets was significantly lower than psychiatric/seizure medications (0.10 vs. 0.93, p < 0.001) and similar to nutraceuticals (0.16). Autism severity decreased slightly over time in participants who used diet vs. increasing slightly in those that did not ( p < 0.001). Healthy and Feingold diets were the two top-rated diets by Overall Benefit; the ketogenic diet was the highest for nine symptoms (though had fewer respondents); and the gluten-free/casein-free diet was among the top for overall symptom improvements. Different diets were reported to affect different symptoms, suggesting that an individual's symptoms could be used to guide which diet(s) may be the most effective. The results suggest that therapeutic diets can be safe and effective interventions for improving some ASD-related symptoms with few adverse effects. We recommend therapeutic diets that include healthy foods and exclude problematic foods. Therapeutic diets are inexpensive treatments that we recommend for consideration by most people with ASD.

Sickle cell disease (SCD) is an inherited blood disorder caused by a point mutation in hemoglobin (Hb), the protein in the red blood cell (RBC) responsible for the transport of oxygen (O 2 ) throughout the body. The mutation leads to the expression of sickle cell hemoglobin (HbS). Both Hb and HbS exist in equilibrium between oxygenated and deoxygenated forms; however, deoxygenated HbS can polymerize to form long fibers which distort the shape of RBCs into the characteristic sickled shape. The misshapen RBCs can obstruct blood vessels and capillaries, resulting in a vaso-occlusive crisis. Vaso-occulsion deprives tissues and organs of O 2 and can cause intense pain which often results in hospitalization. Chronic organ damage is a major cause of reduced life expectancy for SCD patients.Allosteric effectors are molecules which regulate protein function. HbS allosteric effectors can be used to decrease polymerization by stabilizing the oxygenated form of HbS, which leads to an increase in O 2 uptake and a decrease in the sickling of RBCs. Allosteric effectors that have been evaluated for the treatment of SCD include vanillin, 5-hydroxymethyl furfural (5-HMF), and voxelotor, which was approved by the U.S. Food and Drug Administration (FDA) for the treatment of SCD in 2019. 5-HMF did not progress to phase III clinical trials since it suffered from rapid metabolic degradation. However, several derivatives of 5-HMF and vanillin have been synthesized and evaluated as potential candidates for SCD treatment. Derivatives of these compounds have shown promise, but their shortcomings, such as high levels of oxidative metabolism, have prevented them from progressing into marketable drugs. Our efforts have produced multiple 5-HMF derivatives which have been evaluated for their potential to treat SCD. Each derivative was evaluated for its ability to increase O 2 affinity (i.e., P 50 , the partial pressure at which hemoglobin is 50% saturated with O 2 ). The synthesized aryl ether derivatives were evaluated, and results suggest that compounds with multiple aromatic aldehydes may have enhanced biological properties. One such derivative, compound 5 , which features two furan aldehyde rings, exhibited increased O 2 affinity ( P 50 = 8.82 ± 1.87 mmHg) over that of unmodified Hb ( P 50 = 13.67 ± 0.22 mmHg). Future studies include obtaining crystal structures of the 5-HMF derivatives complexed with HbS to confirm the protein-allosteric effector interactions.

Since Angus Campbell and colleagues first introduced the "levels of conceptualization" (LoC) framework as a measure of political sophistication, a number of scholars have applied the approach to subsequent American national elections. In this study, we present the first application of the LoC framework to a municipal election, and focus upon the 2018 Toronto mayoral race. After describing the method and data we use to adapt the framework to this new context, we replicate previous analyses, and find that LoC is related to local voter turnout and several measures of political sophistication. We then consider the question of whether major candidates were discussed at different LoC, and if their supporters view local politics at different LoC. We conclude by making the case that the LoC framework is helpful for resolving the debate over whether local politics are ideological or managerial in nature., Competing Interests: Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2021.)

A new metal-organic precursor for the chemical vapor deposition of zinc oxide thin films, [Zn(C 9 H 16 NO 3 ) 2 ], has been synthesized and characterized by 1 H and 13 C NMR spectroscopy, single-crystal X-ray diffraction and thermogravimetric analysis. The asymmetric unit of the title compound consists of two mol-ecules ( Z ' = 2), with different zinc coordination polyhedra. In one mol-ecule, the metal atom is in a distorted trigonal-bipyramidal ZnN 2 O 3 environment (τ 5 = 0.192) with a long bond to an ether O donor atom [Zn-O = 2.727 (6) Å]. In the other, the Zn atom is in a distorted ZnN 2 O 4 octa-hedral environment with long bonds to the ether O donors of both ligands [Zn-O = 2.514 (4) and 2.661 (4) Å; O-Zn-O = 82.46 (14)°]. The crystal structure features weak C-H⋯·O inter-actions., (© Johnson et al. 2022.)

We thank Vorland et al [...].

This study involved a randomized, controlled, single-blind 12-month treatment study of a comprehensive nutritional and dietary intervention. Participants were 67 children and adults with autism spectrum disorder (ASD) ages 3-58 years from Arizona and 50 non-sibling neurotypical controls of similar age and gender. Treatment began with a special vitamin/mineral supplement, and additional treatments were added sequentially, including essential fatty acids, Epsom salt baths, carnitine, digestive enzymes, and a healthy gluten-free, casein-free, soy-free (HGCSF) diet. There was a significant improvement in nonverbal intellectual ability in the treatment group compared to the non-treatment group (+6.7 ± 11 IQ points vs. -0.6 ± 11 IQ points, p = 0.009) based on a blinded clinical assessment. Based on semi-blinded assessment, the treatment group, compared to the non-treatment group, had significantly greater improvement in autism symptoms and developmental age. The treatment group had significantly greater increases in EPA, DHA, carnitine, and vitamins A, B2, B5, B6, B12, folic acid, and Coenzyme Q10. The positive results of this study suggest that a comprehensive nutritional and dietary intervention is effective at improving nutritional status, non-verbal IQ, autism symptoms, and other symptoms in most individuals with ASD. Parents reported that the vitamin/mineral supplements, essential fatty acids, and HGCSF diet were the most beneficial., Competing Interests: J.B.A. is the president of the Autism Nutrition Research Center (ANRC), a non-profit which provides information to autism families and which produces an improved version of the vitamin/mineral supplement used in this study. He serves as an unpaid volunteer, and does not receive any royalties from the sale of the vitamin/mineral supplement. T.A. consults for Health Diagnostics, a commercial testing lab. D.W.Q. works at Doctor’s Data, a commercial testing lab. The other authors do not have any competing interests.

Objectives: To describe and review the Delphi technique as a tool for radiographers engaged in mixed-methods research whereby agreement is required on the proficiencies needed by educational programmes for pre- and post- registration radiographers. This is achieved through a description offering a brief history of the technique. Through a literature search, radiography education research using this technique is identified. A protocol for a research project using the technique is presented. Using this worked example, advantages and disadvantages of the method are explored including sampling of participants, sample size, number of rounds and methods of feedback., Key Findings: There are limited examples of the use of the Delphi technique in radiography literature including considerations on how to select experts and panel size., Conclusion: The Delphi technique is a suitable method for establishing collective agreement in the design of radiography educational interventions. Additional research is needed to deepen this evidence-based knowledge., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

The acclimation of plants to light has been studied extensively, yet little is known about the effect of dynamic fluctuations in light on plant phenotype and acclimatory responses. We mimicked natural fluctuations in light over a diurnal period to examine the effect on the photosynthetic processes and growth of Arabidopsis ( Arabidopsis thaliana ). High and low light intensities, delivered via a realistic dynamic fluctuating or square wave pattern, were used to grow and assess plants. Plants subjected to square wave light had thicker leaves and greater photosynthetic capacity compared with fluctuating light-grown plants. This, together with elevated levels of proteins associated with electron transport, indicates greater investment in leaf structural components and photosynthetic processes. In contrast, plants grown under fluctuating light had thinner leaves, lower leaf light absorption, but maintained similar photosynthetic rates per unit leaf area to square wave-grown plants. Despite high light use efficiency, plants grown under fluctuating light had a slow growth rate early in development, likely due to the fact that plants grown under fluctuating conditions were not able to fully utilize the light energy absorbed for carbon fixation. Diurnal leaf-level measurements revealed a negative feedback control of photosynthesis, resulting in a decrease in total diurnal carbon assimilated of at least 20%. These findings highlight that growing plants under square wave growth conditions ultimately fails to predict plant performance under realistic light regimes and stress the importance of considering fluctuations in incident light in future experiments that aim to infer plant productivity under natural conditions in the field., (© 2017 American Society of Plant Biologists. All Rights Reserved.)

Stomatal pores form a crucial interface between the leaf mesophyll and the atmosphere, controlling water and carbon balance in plants [1]. Major advances have been made in understanding the regulatory networks and ion fluxes in the guard cells surrounding the stomatal pore [2]. However, our knowledge on the role of carbon metabolism in these cells is still fragmentary [3-5]. In particular, the contribution of starch in stomatal opening remains elusive [6]. Here, we used Arabidopsis thaliana as a model plant to provide the first quantitative analysis of starch turnover in guard cells of intact leaves during the diurnal cycle. Starch is present in guard cells at the end of night, unlike in the rest of the leaf, but is rapidly degraded within 30 min of light. This process is critical for the rapidity of stomatal opening and biomass production. We exploited Arabidopsis molecular genetics to define the mechanism and regulation of guard cell starch metabolism, showing it to be mediated by a previously uncharacterized pathway. This involves the synergistic action of β-amylase 1 (BAM1) and α-amylase 3 (AMY3)-enzymes that are normally not required for nighttime starch degradation in other leaf tissues. This pathway is under the control of the phototropin-dependent blue-light signaling cascade and correlated with the activity of the plasma membrane H(+)-ATPase. Our results show that guard cell starch degradation has an important role in plant growth by driving stomatal responses to light., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In Arabidopsis thaliana, changes in metabolism and gene expression drive increased drought tolerance and initiate diverse drought avoidance and escape responses. To address regulatory processes that link these responses, we set out to identify genes that govern early responses to drought. To do this, a high-resolution time series transcriptomics data set was produced, coupled with detailed physiological and metabolic analyses of plants subjected to a slow transition from well-watered to drought conditions. A total of 1815 drought-responsive differentially expressed genes were identified. The early changes in gene expression coincided with a drop in carbon assimilation, and only in the late stages with an increase in foliar abscisic acid content. To identify gene regulatory networks (GRNs) mediating the transition between the early and late stages of drought, we used Bayesian network modeling of differentially expressed transcription factor (TF) genes. This approach identified AGAMOUS-LIKE22 (AGL22), as key hub gene in a TF GRN. It has previously been shown that AGL22 is involved in the transition from vegetative state to flowering but here we show that AGL22 expression influences steady state photosynthetic rates and lifetime water use. This suggests that AGL22 uniquely regulates a transcriptional network during drought stress, linking changes in primary metabolism and the initiation of stress responses., (© 2016 American Society of Plant Biologists. All rights reserved.)

Identity is often studied as a motivational construct within research on adolescent development and education. However, differential dimensions of identity, as a set of internal values versus external perceptions of social belonging, may relate to motivation in distinct ways. Utilizing a sample of 600 African American and Latino adolescents (43% female; mean age = 13.9), the present study examines whether self-regulated learning (SRL) mediates two distinct dimensions of academic identity (i.e., value and belonging) and mastery orientation. This study also examines whether self-efficacy moderates the mediating role of SRL between identity and mastery. Results show evidence for moderated mediation between SRL and academic self-efficacy. Self-regulated learning played its strongest mediating role between belonging and mastery and for low-efficacy students specifically., (© 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.)

Empirical trends denote the academic underachievement of ethnic minority males across various academic domains. Identity-based explanations for this persistent phenomenon describe ethnic minority males as disidentified with academics, alienated, and oppositional. The present work interrogates these theoretical explanations and empirically substantiates a multidimensional lens for discussing academic identity formation within 330 African American and Latino early-adolescent males. Both hierarchical and iterative person-centered methods were utilized and reveal 5 distinct profiles derived from 6 dimensions of academic identity. These profiles predict self-reported classroom grades, mastery orientation, and self-handicapping in meaningful and varied ways. The results demonstrate multiple pathways to motivation and achievement, challenging previous oversimplified stereotypes of marginalized males. This exploratory study triangulates unique interpersonal and intrapersonal attributes for promoting healthy identity development and academic achievement among ethnic minority adolescent males.

Four phosphonate derivates of 2,3-diphosphoglycerate (2,3-DPG), in which the phosphate group is replaced by a methylene or difluoromethylene, were successfully synthesized for use as allosteric modulators of hemoglobin (Hb) O2 affinity. The syntheses were accomplished in four steps and the reagents were converted to their potassium salts to allow for effective binding with Hb in aqueous media. O2 equilibrium measurements of the chemically modified Hbs exhibited P50 values in the range 8.9-12.8 with Hill coefficients in the range of 1.5-2.4.

The title compound, [Zn(C(8)H(14)NO(2))(2)], represents a zinc complex with the Zn(2+) cation coordinated by two O and two N atoms in a distorted tetrahedral geometry.

The authors examined a new assessment of behavioral regulation and contributions to achievement and teacher-rated classroom functioning in a sample (N = 343) of kindergarteners from 2 geographical sites in the United States. Behavioral regulation was measured with the Head-Toes-Knees-Shoulders (HTKS) task, a structured observation requiring children to perform the opposite of a dominant response to 4 different oral commands. Results revealed considerable variability in HTKS scores. Evidence for construct validity was found in positive correlations with parent ratings of attentional focusing and inhibitory control and teacher ratings of classroom behavioral regulation. Hierarchical linear modeling indicated that higher levels of behavioral regulation in the fall predicted stronger levels of achievement in the spring and better teacher-rated classroom self-regulation (all ps < .01) but not interpersonal skills. Evidence for domain specificity emerged, in which gains in behavioral regulation predicted gains in mathematics but not in language and literacy over the kindergarten year (p < .01) after site, child gender, and other background variables were controlled. Discussion focuses on the importance of behavioral regulation for successful adjustment to the demands of kindergarten., (Copyright 2009 APA, all rights reserved)

A novel beta-ketoimine, 4-N-(n-butylamino)-3-penten-2-one (1), and beta-enaminoester, Ethyl 3-N-(isopropylamino)-2-butenoate (2), were synthesized by the reaction of the 2,4-pentanedione or ethyl 3-oxo butanoate with the n-butyl and isopropyl amine, respectively. The isolated free ligands 1 and 2 were reacted with diethylzinc to afford Zn(CH3C(NCH2CH2CH2CH3)CHCOCH3)2 (3) and Zn(CH3C(NCH(CH3)2)CHC(O)OCH2CH3)2 (4) respectively. The isolated zinc complexes, 3 and 4, were characterized by elemental analysis, NMR, and MALDI-TOFMS. The molecular structure of 3 and 4 were determined via single crystal X-ray diffraction which revealed both compounds to be four coordinate, monomeric and homoleptic in the solid state. TG analysis showed the air stable compounds to be thermally robust as they both sublimed in a one-step process at atmospheric pressure. The compounds were utilized in the growth of ZnO via AP-MOCVD in the absence of additional oxidant. The carbon content of the film grown from 3 as determined by XPS was 26.2% while that of the film grown by 4 was 8.71%.

The immunogenicity and safety of a chromatographically purified rabies vaccine (CPRV) was evaluated using US veterinary medical students. In the first study, 242 healthy adults were enrolled in a randomized, modified double-blind, multicenter trial and received five doses of either CPRV or human diploid cell vaccine (HDCV) by intramuscular injection on days 0, 3, 7, 14, and 28 concurrently with human rabies immunoglobulin in a simulated post-exposure prophylaxis regimen. Post-immunization titers in the CPRV and HDCV groups reached 0.5 IU/ml (the WHO-recommended minimally acceptable titer) or greater in all subjects in both vaccine groups by day 14 and remained above that level through day 90. In the second study, 438 healthy adults were enrolled in a randomized, double-blind, multicenter trial and assigned to receive five doses from one of three lots of CPRV by intramuscular injection on days 0, 3, 7, 14, and 28 in a simulated post-exposure prophylaxis regimen to evaluate lot consistency. Post-immunization titers rapidly increased to over 0.5 IU/ml by day 14 for all subjects and remained above that level through day 42 when the study was terminated. The three lots were considered equivalent. The percentage of subjects with at least one local reaction during the five-dose regimen was slightly lower in the CPRV group than in the HDCV group (P=0.06). The most frequently reported local reaction for all doses of vaccine was pain at the injection site. Headache, myalgia, and malaise were the most frequently reported systemic events. The percentage of subjects with at least one systemic event was significantly lower for CPRV (P=0.0084). No vaccine-related serious adverse reaction was reported in these studies. The results of these studies indicate that CPRV administered intramuscularly to healthy adults is immunogenic and is associated with fewer local and systemic reactions than HDCV.

Interleukin 1 (IL-1) activates p42/p44 and p38 mitogen-activated protein kinases (MAP kinases) in target cells. Here we have used two specific inhibitors, PD98059 which inhibits MAP kinase kinase (MEK), and SB203580 which inhibits p38 MAP kinase to explore the involvement of these kinases in the induction of IL-2 by IL-1 in the murine thymoma cell line EL4.NOB-1. Both kinase inhibitors suppressed IL-1-stimulated IL-2 production. PD98059 blocked IL-2 mRNA accumulation and the induction of a reporter gene linked to the IL-2 promoter. In contrast, SB203580 only marginally inhibited IL-2 promoter-linked reporter gene expression and had no inhibitory effect on IL-2 mRNA levels. Neither PD98059 nor SB203580 had an inhibitory effect on NFkappaB-driven reporter gene expression in response to IL-1. Surprisingly, higher concentrations of SB203580 (30 microM) potentiated the IL-1 responses. PD98059 also inhibited induction of IL-2 by phorbol 12-myristate 13-acetate (PMA), and AP1-linked reporter gene expression in response to PMA but not IL-1. These results indicate that p42/p44 MAP kinase is involved in the regulation of IL-2 gene transcription by IL-1, whilst p38 MAP kinase has a post-transcriptional target. Additional IL-1 signalling pathways can clearly compensate for the lack of p38 MAP kinase which result in potentiation of the IL-1 responses observed at high-dose SB203580., (Copyright 1999 Academic Press.)

Protein kinase C (PKC) has been implicated in interleukin 1 (IL1) signal transduction in a number of cellular systems, either as a key event in IL1 action or as a negative regulator. Here we have examined the effects of two PKC inhibitors, staurosporine and the more selective agent Ro 31-8220, on IL1 responses in the murine thymoma line EL4.NOB-1. A 1 h pulse of staurosporine was found to strongly potentiate the induction of IL2 by IL1alpha in these cells. In contrast, neither a pulse nor prolonged incubation with Ro 31-8220 affected the response to IL1alpha. Both agents blocked the response to PMA, however. A 1 h pulse of staurosporine was also found to induce IL2 production on its own, activate the transcription factor nuclear factor kappaB (NFkappaB) and increase the expression of a NFkappaB-linked reporter gene. It synergized with IL1alpha in all of these responses. Ro 31-8220 was again without effect, although both staurosporine and Ro 31-8220 blocked the activation of NFkappaB by PMA. Finally, staurosporine caused the translocation of PKC-alpha and -epsilon, and to a lesser extent PKC-beta, but not PKC-&theta; or -zeta, from the cytosol to the membrane, although a similar effect was observed with Ro 31-8220. The results suggest that PKC is not involved in IL1alpha signalling in EL4 cells. Furthermore, the potentiating effect of staurosporine on IL1alpha action does not involve PKC inhibition, and is likely to be at the level of NFkappaB activation.

Pretreatment (18 h) of the bovine aortic endothelial cell line AG4762 to 500 microM sodium nitroprusside (SNP), glyceryl trinitrate (GTN) or 3-morpholino-sydnonimine (SIN-1) significantly inhibited 100 nM bradykinin-stimulated prostacyclin (PGI2) release. SIN-1 produced the greatest reduction (67 +/- 6%), followed by SNP (47 +/- 12%) and GTN (45 +/- 9%). Only SIN-1 and GTN inhibited basal PGI2 release where again the effect of SIN-1 (66 +/- 6%) was greater than that of GTN (31 +/- 15%). There was no effect of SNP on basal PGI2 release. We have demonstrated this inhibition of bradykinin-stimulated PGI2 release is not the result of cell death. In addition, 8-bromo-cyclic GMP, whilst having no effect on basal PGI2 release, demonstrated a small but significant inhibition (15 +/- 6%) of the enhanced response to 100 nM bradykinin. These studies may reflect a mechanism by which the release of vasodilators from endothelial cells is altered during therapy with nitrovasodilators and thus may contribute to the development of tolerance to these drugs.

1. The 16-phenoxy prostaglandin E analogue sulprostone consistently potentiates primary aggregation waves induced by adenosine 5'-diphosphate (ADP), PAF and 11,9-epoxymethano PGH2 (U-46619) in platelet-rich plasma from human donors. The effect is not blocked by the TP-receptor antagonists, EP 092 and GR 32191. The high potency of sulprostone (threshold concentration = 4-10 nM) and the weak block of sulprostone potentiation by the EP1-receptor antagonist, AH 6809 (pA2 = 4.3) suggest the involvement of EP3-receptors as opposed to EP1- or EP2-subtypes. 2. Eight prostaglandin E (PGE) analogues were compared against sulprostone for their effects on PAF-induced aggregation in human platelet-rich plasma (PRP) in the presence of GR 32191 and the DP-receptor antagonist, BW A868C. PGE2 and 11-deoxy PGE2-1-alcohol showed evidence of both potentiating and inhibitory actions and butaprost showed only inhibitory activity at high concentrations. The remaining analogues always elicited potentiation, with the following potency ranking: sulprostone = 16,16-dimethyl PGE2 > MB 28767 > misoprostol > GR 63779X = 17-phenyl-omega-trinor PGE2. The results again indicate that EP3- rather than EP1- or EP2-receptors are involved. However, relative potentiating potency could be affected by differences in plasma protein binding and the very high sensitivity of the human platelet to prostacyclin (IP)-receptor-mediated inhibition (IC50 for the specific IP-receptor agonist cicaprost = 0.8 nM). 3. On human washed platelet suspensions the PGE analogues, with the exception of butaprost,inhibited the rise in adenosine 3':5'-cyclic monophosphate (cyclic AMP) induced by cicaprost (8 nM).PGE2 produced a monophasic inhibition curve (IC50 = 5.4 nM, 92% inhibition at 600 nM). The potency ranking was 16,16-dimethyl PGE2> sulprostone>MB 28767 = PGE2> misoprostol> GR 63778X>17-phenyl-w-trinor PGE2> 1 1-deoxy PGE2-1-alcohol. AH 6809 inhibited the effect of sulprostone and 17-phenyl-c-trinor PGE2 with pA2 values of 5.75 and 5.32 respectively; these values are at least one log unit lower than those found for EP1-receptor block in smooth muscle.4. There is a statistically significant correlation between IC50 values for the PGE analogues on the human platelet cyclic AMP assay and the guinea-pig vas deferens (standard EP3 preparation): slope =1.00, r = 0.80, P <0.05. However the correlation is far from ideal and GR 63779X in particular has a lower potency in the cyclic AMP assay. At this time we suggest that it is prudent to describe the human platelet receptor as 'EP3-like'.5. We believe that our results provide further evidence for linking PGE-induced potentiation of aggregation to inhibition of adenylate cyclase. Sulprostone is a suitable agonist for further study of this system and in particular the nature of the G-protein linkage(s) involved. In addition the necessity to consider potentiation of platelet aggregation in -relation to the clinical use of PGE analogues in man is emphasised.

Cycloheximide produced a large increase in prostaglandin (PG) E2 output and smaller increases in PGF2 alpha and 6-keto-PGF1 alpha when superfused over the guinea-pig uterus for 20 min. This stimulation of the outputs of these 3 PGs by cycloheximide did not require extracellular calcium. TMB-8 (an intracellular calcium antagonist) had no effect on the stimulation of PGE2 output by cycloheximide, but it completely prevented the stimulation of PGF2 alpha and 6-keto-PGF1 alpha outputs. W-7 (a calmodulin antagonist) had no effect on the stimulation of PGE2 and PGF2 alpha outputs by cycloheximide, but it partially reduced and delayed the stimulation of 6-keto-PGF1 alpha output. Neomycin (a phospholipase C inhibitor) did not prevent the increases in PGE2 and 6-keto-PGF1 alpha outputs produced by cycloheximide. However, neomycin (5 and 10 mM, but not 1 mM) inhibited the small increases in PGF2 alpha caused by cycloheximide. On its own, neomycin produced a dose-dependent, transient increase in 6-keto-PGF1 alpha output without affecting the outputs of PGF2 alpha and PGE2. It is concluded that different mechanisms are involved in the processes by which cycloheximide stimulates the syntheses of PGE2, PGF2 alpha and 6-keto-PGF1 alpha in the guinea-pig uterus.

Fresh fecal material that was free of ova and parasites was pooled with 10% Formalin in a 1:4 ratio to prepare a standard specimen. Portions of 100 ml of this specimen were individually seeded with Cryptosporidium oocysts, Entamoeba coli, Entamoeba histolytica, and Giardia lamblia cysts; ova of Necator americanus; and Strongyloides larvae. Appropriate volumes of each parasite suspension were used to evaluate the Fecal Concentrator Kit (Remel, Lenexa, Kans.), Fecal Parasite Concentrator (Evergreen Scientific, Los Angeles, Calif.), Para-Pak Macro-Con (Meridian Diagnostics, Inc., Cincinnati, Ohio), and Trend FeKal CON-Trate (Trend Scientific, Inc., St. Paul, Minn.). A standardized gauze filtration method was used as the reference procedure. Tests were performed in triplicate with each individual parasite-concentrator combination, with three slides examined from each sediment. All of the systems effectively concentrated parasites compared with direct examination of unconcentrated fecal material. The Fecal Concentrator Kit provided the best overall performance. Clarity of sediment, lack of debris, and uniformity of background material were found to be important considerations for microscopic detection of parasites in concentrated specimens.

Microscopy and leukocyte esterase activity, both employed as screening techniques for urine cultures, were evaluated with respect to two distinct populations, male and female. When 424 urine specimens from males were examined, 95% of the Gram-stained smears and 91% of the leukocyte esterase tests correctly correlated with culture results, indicating significant bacteriuria. There were no significant differences between the Gram stain and leukocyte esterase activity in predicting a negative culture: 99% and 98%, respectively. Neither microscopy nor esterase activity proved as sensitive or as efficient in predicting a negative culture with the female population.

Three commercially available systems, the 4-h Minitek Enterobacteriaceae III, the Haemophilus Trio-Tube, and the Micro-ID, were evaluated for their capacities to identify and biotype 308 respiratory isolates of Haemophilus spp. When compared with aminolevulinic acid test results, the definitive identification method used in this study, these systems demonstrated no significant differences in their capacities to differentiate Haemophilus influenzae from Haemophilus parainfluenzae. They were in agreement with the standard method of species identification approximately 50% of the time. When sucrose was added to the Minitek and Trio-Tube configurations, the efficiency rate of species identification increased to more than 95%. The Micro-ID could not be modified to incorporate this additional biochemical parameter. The performance of the sucrose-supplemented Minitek and Trio-Tube systems, compared to the combined results of Micro-ID and aminolevulinic acid, produced correlations of 94 and 90%, respectively. Rapid and accurate methodologies are available for combined species identification and biotyping of Haemophilus spp.