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In Syrian hamsters, socially relevant information is communicated with a form of scent marking known as flank marking. There is substantial evidence that arginine-vasopressin acting on V 1a vasopressin receptors (V 1a R) in the medial preoptic-anterior hypothalamic continuum (MPOA-AH) regulates the expression of flank marking. Previous studies have shown that the expression of flank marking is also influenced by the circulating concentrations of gonadal hormones. In hamsters housed in long 'summer-like' photoperiods (i.e. >12.5 h of light/day), castration reduces flank marking and administration of testosterone restores precastration levels of flank marking. When exposed to short 'winter-like' photoperiods (i.e. < 12.5 h of light/day), hamsters undergo gonadal regression and the circulating levels of testosterone decline. Surprisingly, flank marking induced during social encounters is not reduced in hamsters exposed to short photoperiods despite the low circulating concentrations of testosterone. In the present study, it was hypothesized that reductions in testosterone, caused by exposure to short photoperiod, would not reduce the ability of vasopressin to stimulate flank marking by its actions in the MPOA-AH. The amount of flank marking induced by vasopressin injected into the MPOA-AH did not significantly differ between hamsters housed in long and short photoperiods; however, short photoperiod-exposed males had significantly less V 1a R binding in the MPOA than long photoperiod-exposed males. These results support the hypothesis that the sensitivity of the MPOA-AH to vasopressin is not reduced in short photoperiod-exposed males, despite decreases in serum testosterone. However, by contrast to our predictions, short photoperiod-exposed males have significantly reduced V 1a R binding in the MPOA-AH compared to long photoperiod-exposed males.

In vitro quantification of the catalytic activity of an enzyme isoform requires the availability of selective agents that allow for either measurements in the presence of the other enzyme isoforms or purification of the isoform and subsequent performance of these measurements on the purified enzyme. Isozyme-specific antibodies are useful tools for these types of analyses. In the present report, we detail a method for the measurement of phospholipase C-gamma1 enzyme activity employing native enzyme that is immobilized on microtiter plates. The method uses biotinylated antiglobulin bound to streptavidin-coated microtiter plates to immobilize antiphospholipase C-gamma1 antibody and subsequently capture phospholipase C-gamma1 from brain tissue lysates. This method avoids biotinylation of the primary (antiphospholipase C-gamma1) antibody, making it less labor intensive than previously described methods for using streptavidin-coated plates; in addition, it is highly reproducible and sensitive and allows for quantification of enzyme activity. We employ the technique to show that one or more tyrosine kinases copurify with rat brain phospholipase C-gamma1. The method is applicable to the study of any enzyme isoform for which antibodies that capture the native form of the enzyme are available and could easily be employed in high-throughput procedures.

The motivation to engage in social behaviors is influenced by past experience and internal state, but also depends on the behavior of other animals. Across species, the oxytocin (Oxt) and vasopressin (Avp) systems have consistently been linked to the modulation of motivated social behaviors. However, how they interact with other systems, such as the mesolimbic dopamine system, remains understudied. Further, while the neurobiological mechanisms that regulate prosocial/cooperative behaviors have been extensively examined, far less is understood about competitive behaviors, particularly in females. In this chapter, we highlight the specific contributions of Oxt and Avp to several cooperative and competitive behaviors and discuss their relevance to the concept of social motivation across species, including humans. Further, we discuss the implications for neuropsychiatric diseases and suggest future areas of investigation.

We investigated a novel strategy for measuring the synthesis rate of proteins in skeletal and cardiac muscle. Mass isotopomer distribution analysis allows measurement of the isotopic enrichment of the true biosynthetic precursor for proteins (tRNA-amino acids), but cannot easily be applied to slow turnover muscle proteins due to insufficient isotope incorporation into multiply labeled species. Using a rapid turnover protein from the same tissue, however, might reveal tRNA-amino acid enrichment. We tested this strategy in rats on muscle creatine kinase (CK). A trypsinization peptide (3647 u) containing 5 leucine repeats was identified by computer-simulated digestion of CK and then isolated from trypsin hydrolysates. Mass isotopomer abundances were determined by electrospray ionization-magnetic sector-mass spectrometry after in vivo administration of [ 2 H 3 ]leucine. Myosin heavy chain was also isolated and hydrolyzed to free amino acids. Muscle tRNA-amino acids were well labeled, by direct measurement. Enrichments of M+1 and M+2 mass isotopomers in the CK-peptide were measurable but low (consistent with a CK half-life of 3–10 days). Incorporation into skeletal muscle myosin indicated a half-life of 54 days. In conclusion, the general strategy of measuring protein kinetics by quantifying mass isotopomer abundances of mid-sized peptides from protein hydrolysates is effective, but CK does not turn over rapidly in muscle, contrary to previous reports. Identification of a rapid turnover muscle protein would be useful for this purpose.

One brain region that has been implicated in the regulation of lordosis is the medial preoptic-anterior hypothalamic continuum (MPOA-AH). Previous studies have suggested that this zone may be part of the circuit mediating the effects of serotonin (5-HT) on sexual receptivity. In the present experiments, we investigated the role of 5-HT 1a/7 and 5-HT 2 receptor subtypes in the MPOA-AH in the control of lordosis. In two experiments, either 5-HT 1a/7 or 5-HT 2 agonists were injected unilaterally into the MPOA-AH of ovariectomized, hormonally primed female hamsters. In the first experiment, microinjections of the 5-HT 1a/7 agonist 8-hydroxy-2,9-(di- n -propylamino)tetralin resulted in an attenuation of the lordosis posture by causing a decrease in the mean lordosis duration and an increase in the number of lordosis episodes over the entire testing period. In the second experiment, microinjections of the 5-HT 2b/2c agonist m -chlorophenylpiperazine did not result in any changes in sexual receptivity. However, microinjections of the 5-HT 2 agonist (2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl facilitated lordosis by increasing the mean lordosis duration and decreasing the number of lordosis episodes in the first 5 min of the testing period. These data indicate that serotonin may act in the MPOA-AH via 5-HT 1a/7 receptors to attenuate and 5-HT 2 receptors to facilitate sexual receptivity.

The purpose of this study was to evaluate embedding and distributing constant time delay instructional trials into circle time activities and transitions between activities. Three boys in a summer day camp participated, and their teachers implemented the instruction. A multiple probe design across behaviors and replicated across participants was used. The data indicated (a) the teachers embedded and distributed the instruction accurately; (b) the children acquired the behaviors they were taught; (c) the trials to criterion and percentage of errors were similar, in large part, with what occurs when constant time delay is used in structured instructional sessions; and (d) the children generalized the learned behaviors across adults and materials. The findings are discussed in terms of our existing knowledge about embedding instruction in inclusive activities.

The preputial glands of house mice express the gene for the fifth melanocortin receptor (MC5-R) and are a primary source of urinary pheromones involved in inter-male aggression. A 'resident-intruder' behavioral model was used to compare the responses of resident males to urine from mice with an engineered disruption of the fifth melanocortin receptor (MC5-RKO) with residents' responses to urine from wild-type mice (WT). Each type of urine was presented in combination with a castrated intruder male to provide the appropriate biological context. Resident males responded with a longer latency to bite when the urine was from gonadally intact WT males compared with urine from MC5-RKO mice. These results are consistent with the hypothesis that activation of the fifth melanocortin receptor in the preputial glands of male house mice causes excretion of urinary pheromones that delay aggressive responses by other males.

The function of the CA2 region of the hippocampus is poorly understood. While the CA1 and CA3 regions have been extensively studied, for years the CA2 region has primarily been viewed as a linking area between the two. However, the CA2 region is known to have distinct neurochemical and structural features that are different from the other parts of hippocampus and in recent years it has been suggested that the CA2 region may play a role in the formation and or recall of olfactory-based memories needed for normal social behavior. While this hypothesis has been supported by hippocampal lesion studies that have included the CA2 region, no studies have attempted to specifically lesion the CA2 region of the hippocampus in mice to determine the effects on social recognition memory and olfaction. To fill this knowledge gap, we sought to perform excitotoxic N-methyl-D aspartate (NMDA) lesions of the CA2 region in mice and determine the effects on social recognition memory. We predicted that lesions of the CA2 region would impair social recognition memory. We then went on to test olfaction in CA2 lesioned mice since social memory requires a functional olfactory system. Consistent with our prediction, we found that CA2 lesioned animals have impaired social recognition. These findings are significant because they confirm that the CA2 region of the hippocampus is a part of the neural circuitry that regulates social recognition memory, which may have implications for our understanding of the neural regulation of social behavior across species.

The D3-phosphoinositides act as second messengers by recruiting, and thereby activating, diverse signaling proteins. We have previously described the purification of a rat phosphatidylinositol 3-phosphate [PtdIns(3)P] 3-phosphatase, comprising a heterodimer of a 78-kDa adapter subunit in complex with a 65-kDa catalytic subunit. Here, we have cloned and characterized the cDNA encoding the human 3-phosphatase adapter subunit (3-PAP). Sequence alignment showed that 3-PAP shares significant sequence similarity with the protein and lipid 3-phosphatase myotubularin, and with several other members of the myotubularin gene family including SET-binding factor 1. However, unlike myotubularin, 3-PAP does not contain a consensus HCX 5 R catalytic motif. The 3-PAP sequence contains several motifs that predict interaction with proteins containing Src homology-2 (SH2) domains, phosphotyrosine-binding (PTB) domains, members of the 14-3-3 family, as well as proteins with SET domains. Northern blot analysis identified two transcripts (5.5 kb and 2.5 kb) with highest abundance in human liver, kidney, lung, and placenta. 3-PAP immunoprecipitates isolated from platelet cytosol hydrolyzed the D3-phosphate from PtdIns(3)P and PtdIns 3,4-bisphosphate [PtdIns(3,4)P 2 ]. However, insect cell-expressed 3-PAP recombinant protein was catalytically inactive, confirming our prior prediction that this polypeptide represents an adapter subunit.

Serotonin (5-hydroxytryptamine, 5-HT) plays a central role in several behaviors in marine molluscs and other species. In an effort to better understand the regulation of 5-HT synthesis, we used high performance liquid chromatography (HPLC) with electrochemical detection and immunohistochemistry to measure and map the distribution of the immediate precursor of 5-HT, 5-hydroxytryptophan (5-HTP), in two model opisthobranch molluscs, the nudibranch Tritonia diomedea and the anaspid Aplysia californica. HPLC measurements showed that 5-HTP is present at approximately the same level as the 5-HT metabolite, 5-hydroxyindolacetic acid (5-HIAA) but is more than 100 times lower in concentration than either 5-HT or dopamine in the same tissue. Specific 5-HTP immunoreactivity was colocalized with serotonin in both species. The overall intensity of 5-HTP immunoreactivity in individual ganglia agreed with HPLC measurements for those ganglia. The intensity of 5-HTP immunolabeling varied between cell types and was correlated with the intensity of 5-HT immunolabeling. In particular, differences in staining intensity were consistently seen among the three dorsal swim interneurons of the Tritonia swim central pattern generator circuit. Some nonserotonergic neurons also displayed low levels of 5-HTP immunolabeling that were above background levels. Together, these results support the notion that production of 5-HTP is a rate-limiting step in serotonin synthesis and suggest that there may be additional regulation that allows 5-HTP to accumulate to varying levels. J. Comp. Neurol. 437:91–105, 2001. © 2001 Wiley-Liss, Inc.

For each prime p, let p# be the product of the primes less than or equal to p. We have greatly extended the range for which the primality of n! ± 1 and p# ± 1 are known and have found two new primes of the first form (6380! + 1, 6917! - 1) and one of the second (42209# + 1). We supply heuristic estimates on the expected number of such primes and compare these estimates to the number actually found.

Books reviewed: Richard N.L. Andrews, Managing the Environment—Managing Ourselves: A History of American Environmental Policy Rosemary O'Leary, Robert F. Durant, Daniel J. Fiorino, and Paul Weiland, Managing for the Environment: Understanding Legal, Organizational, and Policy Changes

Subsurface drainage discharge nitrate–N (NO3–N) losses were evaluated under corn during a three year period under three replicated drainage systems: i) 100 mm diameter drainage tile at 80 cm depth; ii) 50 mm diameter drainage tile at 80 cm depth and iii) 50 mm diameter drainage tile at 50 cm depth. Each drainage system had 12 m spacings between laterals. The field under investigation possessed shallow, imperfectly–to–poorly drained soils. Throughout the investigation average NO3–N concentrations in the drainage outflow were similar for all three systems ranging from 9.6–11.4 mg L−1. Total drainage discharge was significantly lower for the shallow (50 cm) system compared to the two deeper (80 cm) systems. Therefore, significant differences in total NO3–N loss between the shallow (50 cm) and deep (80 cm) systems were observed with shallow systems providing reduced NO3–N losses. Corn yields were significantly lower in the shallow (50 cm) drainage treatment in only one year. Shallow drainage may have many eco...

A symposium has been defined as a collection of essays on a particular subject and as a philosophical or other focused discussion. It derives from a Greek origin meaning a drinking party. The focus of this symposium is on the published version of a plenary address given in Boston at the Eighteenth Annual Meeting of the Association for Politics and the Life Sciences, on September 4, 1998. The article, “Is Humanity Destined to Self-Destruct?” was printed in the preceding issue of this journal (1999a). Because not all readers of the present issue may have seen the article toward which the preceding commentaries are directed, a brief summary of its argument follows here:As the twenty-first century approaches, we may identify both constructive and destructive trends that will influence the future. Which set of trends will dominate is uncertain. Attitudes, beliefs, and behaviors all interact to direct the flow of change over time. However, the options and constraints of human life are ultimately fixed by those elements of the environment over which humans have little control. The modem assumption of a world without end or limits risks collision with the obdurate reality called “nature.” Facing threats to its survival, humanity is challenged to learn how to build a sustainable future. A successful effort will require a concerted and cooperative effort among all fields of knowledge. The threats are both “natural” and “societal.” Humanity is an inseparable part of its planetary environment. Chaos and conflict in human society, shortsightedness and indifferences, delay the cooperative action needed to move toward a sustainable future. We do not know how much time we have to avoid catastrophic collision with the hard realities of the planet Earth. This article identifies some of the trends that threaten humanity's future and suggests four lines of action that should be pursued in order to reduce the likelihood that humanity will inadvertently destroy itself.

Inositol polyphosphate 4-phosphatase (4-phosphatase) is an enzyme that catalyses the hydrolysis of the 4-position phosphate from phosphatidylinositol 3,4-bisphosphate [PtdIns(3,4) P 2 ]. In human platelets the formation of this phosphatidylinositol, by the actions of phosphatidylinositol 3-kinase (PI 3-kinase), correlates with irreversible platelet aggregation. We have shown previously that a phosphatidylinositol 3,4,5-trisphosphate 5-phosphatase forms a complex with the p85 subunit of PI 3-kinase. In this study we investigated whether PI 3-kinase also forms a complex with the 4-phosphatase in human platelets. Immunoprecipitates of the p85 subunit of PI 3-kinase from human platelet cytosol contained 4-phosphatase enzyme activity and a 104-kDa polypeptide recognized by specific 4-phosphatase antibodies. Similarly, immunoprecipitates made using 4-phosphatase-specific antibodies contained PI 3-kinase enzyme activity and an 85-kDa polypeptide recognized by antibodies to the p85 adapter subunit of PI 3-kinase. After thrombin activation, the 4-phosphatase translocated to the actin cytoskeleton along with PI 3-kinase in an integrin- and aggregation-dependent manner. The majority of the PI 3-kinase/4-phosphatase complex (75%) remained in the cytosolic fraction. We propose that the complex formed between the two enzymes serves to localize the 4-phosphatase to sites of PtdIns(3,4) P 2 production.

As the twentieth century ends, we may identify both constructive and destructive trends that will influence the future of humanity. Which set of trends will dominate the future is uncertain. Attitudes, beliefs, and behaviors all interact to direct the flow of change over time. However, the options and constraints of human life are ultimately fixed by those cosmic elements of the environment over which humans have no control. The modern assumption of a world without end or limits risks collision with that obdurate reality. Facing threats to its long-term survival, humanity is challenged to learn how to build a sustainable future. A successful effort will require a concerted and cooperative effort among all fields of knowledge. This article identifies some of the trends that threaten humanity's future and suggests four lines of action that should be pursued in order to reduce the likelihood that humanity will destroy itself.

Previous studies in this laboratory have shown that polycyclic aromatic hydrocarbons, such as benzo[a]pyrene (BaP), and certain halogenated aromatic hydrocarbons, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), modulate receptor signaling pathways in human lymphoid and non-lymphoid cells. We have recently demonstrated that BaP produces a weak mitogenic signal in human mammary epithelial cells, perhaps by mimicking growth factor signaling pathways. In the present studies we found that BaP and TCDD activated insulin-like growth factor (IGF-I) signaling pathways under insulin-deficient conditions. The effects of BaP and TCDD were evaluated in the human MCF-10A mammary epithelial cell line grown under epidermal growth factor- and insulin-dependent conditions. BaP (0.3 microM) and TCDD (30 nM) were found to restore a moderate insulin-like signal in MCF-10A cells grown in the absence of added insulin. TCDD was more potent and produced better activation of cell growth than did BaP. Both TCDD and BaP appeared to mimic signaling through the IGF-I receptor (IGF-IR), as evidenced by increased tyrosine phosphophorylation of IGF-IRbeta, IRS-1 and Shc. In addition, both BaP and TCDD significantly increased the activity of phosphatidylinositol 3-kinase (PI3K). The PI3K inhibitor LY294002 was found to inhibit the growth-promoting effects of TCDD seen under insulin-deficient conditions. The results of these studies show that under certain conditions BaP and TCDD can mimic growth factor signaling pathways in human mammary epithelial cells, demonstrating that environmentally prevalent carcinogenic compounds may alter cell growth in human mammary epithelial cells via mimicry of growth factor receptor signaling pathways.

In RBL-2H3 tumor mast cells, cross-linking the high affinity IgE receptor (FcepsilonRI) with antigen activates cytosolic tyrosine kinases and stimulates Ins(1,4,5)P3 production. Using immune complex phospholipase assays, we show that FcepsilonRI cross-linking activates both PLCgamma1 and PLCgamma2. Activation is accompanied by the increased phosphorylation of both PLCgamma isoforms on serine and tyrosine in antigen-treated cells. We also show that the two PLCgamma isoforms have distinct subcellular localizations. PLCgamma1 is primarily cytosolic in resting RBL-2H3 cells, with low levels of plasma membrane association. After antigen stimulation, PLCgamma1 translocates to the plasma membrane where it associates preferentially with membrane ruffles. In contrast, PLCgamma2 is concentrated in a perinuclear region near the Golgi and adjacent to the plasma membrane in resting cells and does not redistribute appreciably after FcepsilonRI cross-linking. The activation of PLCgamma1, but not of PLCgamma2, is blocked by wortmannin, a PI 3-kinase inhibitor previously shown to block antigen-stimulated ruffling and to inhibit Ins(1,4,5)P3 synthesis. In addition, wortmannin strongly inhibits the antigen-stimulated phosphorylation of both serine and tyrosine residues on PLCgamma1 with little inhibition of PLCgamma2 phosphorylation. Wortmannin also blocks the antigen-stimulated translocation of PLCgamma1 to the plasma membrane. Our results implicate PI 3-kinase in the phosphorylation, translocation, and activation of PLCgamma1. Although less abundant than PLCgamma2, activated PLCgamma1 may be responsible for the bulk of antigen-stimulated Ins(1,4,5)P3 production in RBL-2H3 cells.

We evaluated the safety and efficacy of closed-loop therapy with meal announcement during reduction and omission of meal insulin boluses in adolescents with type 1 diabetes (T1D). Twelve adolescents with T1D [six male; mean (s.d.) age 15.9 (1.8) years; mean (s.d.) glycated haemoglobin (HbA1c) 77 (27) mmol/mol] were studied in a randomized crossover study comparing closed-loop therapy with meal announcement with conventional pump therapy over two 24-h stays at a clinical research facility. Identical meals were given on both occasions. The evening meal insulin bolus was calculated to cover half of the carbohydrate content of the meal and no bolus was delivered for lunch. Plasma glucose levels were in the target range of 3.9-10 mmol/l for a median [interquartile range (IQR)] of 74 (55,86)% of the time during closed-loop therapy with meal announcement and for 62 (49,75)% of the time during conventional therapy (p = 0.26). Median (IQR) time spent with plasma glucose levels10 mmol/l [23 (13,39) vs. 27 (10,50)%; p = 0.88] or3.9 mmol/l [1(0,4) vs. 5 (1,10)%; p = 0.24] and mean [standard deviation (SD)] glucose levels [8.0 (7.6,9.3) vs. 7.7 (6.6,10.1) mmol/l, p = 0.79] were also similar. In conclusion, these results assist home testing of closed-loop delivery with meal announcement in adolescents with poorly controlled T1D who miscalculate or miss meal insulin boluses.

Previous studies in our laboratory using a rat model of fetal alcohol exposure (FAE) suggest that FAE-induced behavioral deficits are, in part, linked to neurochemical and electrophysiological deficits in long-term potentiation (LTP) in the entorhinal cortical perforant path projection to the hippocampal formation. Several findings suggest that signal-activated phospholipase C (PLC) and phospholipase A 2 (PLA 2 ) are critical to the induction and maintenance of LTP. Thus, alterations in phospholipid metabolism may play a significant role in the LTP deficits observed in FAE offspring. To test this hypothesis, we measured PLC-β1 and PLA 2 activities in the hippocampus and medial frontal cortex of adult rats prenatally exposed to ethanol. PLC-β1 acidifies were significantly decreased by 20 to 30% in both the hippocampus and medial frontal cortex of FAE rats, compared with ad libitum and pair-fed controls. Total Ca 2+ -dependent PLA 2 activity was 25% lower in the medial frontal cortex of FAE rats, but did not significantly differ from controls in the hippocampal formation. Approximately 30% of the measured activity in both the medial frontal cortex and hippocampal formation of ad libitum and pair-fed animals was associated with an 85 kDa cytosolic PLA 2 form. Cytosolic PLA 2 activities were significantly reduced in both the medial frontal cortex and hippocampal formation of FAE rats, compared with controls. These changes in Ca 2+ -dependent PLA 2 and PLC-β1 activities, coupled with reports of FAE-induced deficits in protein kinase C activity, indicate that prenatal exposure to moderate quantities of ethanol causes profound and long-lasting deficits in the cellular signaling mechanisms associated with activity-dependent synaptic plasticity and memory formation.

The metabolic peptide hormone nesfatin-1 has been linked to the reproductive axis in fishes. The purpose of this study was to determine how energy availability after spawning affects plasma levels of nesfatin-1, the metabolic peptide hormone ghrelin, and sex steroid hormones in rematuring female rainbow trout (Oncorhynchus mykiss). To limit reproductive maturation, a group of female trout was food-restricted after spawning and compared with a control group that was fed a standard broodstock ration. The experiment was conducted twice, once using two-year-old trout (second-time spawners) and once using three-year-old trout (third-time spawners). During monthly sampling, blood was collected from all fish, and a subset of fish from each treatment was sacrificed for pituitaries. Pituitary follicle-stimulating hormone-beta (fsh-β) mRNA expression was analyzed with q-RT-PCR; plasma hormone levels were quantified by radioimmunoassay (17β-estradiol and ghrelin) and enzyme-linked immunosorbent assay (11-keto-testosterone and nesfatin-1). Although plasma nesfatin-1 levels increased significantly in the months immediately after spawning within both feeding treatments, plasma nesfatin-1 did not differ significantly between the two treatments at any point. Similarly, plasma ghrelin levels did not differ significantly between the two treatments at any point. Food restriction arrested ovarian development by 15–20 weeks after spawning, shown by significantly lower plasma E2 levels among restricted-ration fish. Pituitary fsh-β mRNA levels were higher among control-ration fish than restricted-ration fish starting at 20 weeks, but did not differ significantly between treatment groups until 30 weeks after spawning. Within both treatment groups, plasma 11-KT was elevated immediately after spawning and rapidly decreased to and persisted at low levels; starting between 20 and 25 weeks after spawning, plasma 11-KT was higher among control-ration fish than restricted-ration fish. The results from these experiments do not provide support for plasma nesfatin-1 as a signal for the initiation of reproductive development in rematuring female rainbow trout.

To determine how energy balance affects metabolic hormones hypothesized to play a role in the onset of a new reproductive cycle in iteroparous salmonids, food availability after spawning was restricted in female rainbow trout. These fish were compared with a control group that was fed a standard brood stock ration. Bodyweight, length, and muscle lipid content were determined, and blood was collected from fish at regular intervals; a subset of fish from each group was sacrificed at each sampling time for the collection of liver and ovary tissue, and to calculate hepatosomatic index (HSI) and gonadosomatic index (GSI). Plasma hormone levels were quantified by radioimmunoassay, and tissue gene expression levels were analyzed using q-RT-PCR. The experiment was conducted twice, using two-year-old and three-year-old post-spawned fish. Food-restriction arrested ovarian growth and development within 15–20 weeks, as evidenced by lower GSI in restricted-ration fish. Food restriction also reduced Fulton’s condition factor, muscle lipid content, and specific growth rate from one month onward, and reduced HSI after 3 months. In the liver, insulin-like growth factor ( igf1 and igf2 ) gene expression was reduced in three-year-old food-restricted fish within 2 months; however, no effect of ration on igf1 or igf2 expression was detected in two-year-old fish. In both years, IGF binding protein-1 ( igfbp1 ) gene expression decreased over time in both treatment groups. Liver leptin ( slepA1 ) gene expression was lower in two-year-old food-restricted fish at 4 months. These results show that this feed restriction regime arrested reproductive development and affected factors associated with energy balance purported to play a role in initiating reproductive development within 2–4 months after spawning.

The effects of embedding a constant time delay procedure into an independent seat work activity and using instructive feedback were evaluated in this study. Seven students with mild disabilities participated in the study that occurred in their special education classroom. A multiple probe design across sets of target behaviors was used, and students' responses to instructive feedback stimuli were evaluated during each probe condition. The procedures were implemented with a high degree of fidelity, and the results indicate that (a) the students acquired the target behaviors taught with the constant time delay procedure that was embedded into independent seat work, and (b) the students acquired some but not all of the responses to the instructive feedback stimuli. These findings are discussed in terms of using instructive feedback in classrooms and future research on instructive feedback.

A mail survey of elementary education teachers was conducted to identify their perceptions of the necessity and availability of various resources and supports for including students with disabilities in their classrooms. Of the 2,100 questionnaires mailed to kindergarten through Grade 6 teachers, 1,430 (68.1%) were returned in usable form with at least 64% from each grade level and at least 65% returned from each geographic region of the United States. Based on the respondents' ratings, they were divided into three groups: teachers with no students who had disabilities, teachers with students whom they rated as lower in areas of disability, and teachers with students whom they rated as higher in areas of disability. The results indicated that (a) the three groups of teachers did not differ in the level of reported availability of resources/supports, (b) both groups of teachers with children who had disabilities reported greater need for than availability of most resources and supports, (c) larger percentages of teachers with students rated as high in disability areas reported needing the resources/supports than the teachers with students who were rated as lower in disability areas, and (d) greater discrepancies between the levels of need and availability occurred for the teachers with high- and low-rated students. The implications of these findings for inclusive schooling are discussed.

This study evaluated the effects of daily probes of instructive feedback stimuli on students' acquisition of two types of instructive feedback responses. Four students, two with disabilities, participated and were taught four sets of behaviors, two sets received daily probes and two sets did not. A modification of the multiple probe design across behaviors was used. The findings indicate that students acquired their target behaviors rapidly and maintained correct responding during subsequent probe conditions. Students also acquired both types of instructive feedback and maintained it across subsequent probe conditions. The daily probes of the instructive feedback stimuli did not appear to enhance acquisition or maintenance of the instructive feedback responses, but students appeared to acquire the instructive feedback responses while learning their target behaviors. The implications of this study for understanding how students learn instructive feedback responses and for practice are discussed.

Two mail surveys, one with a follow-up, were conducted to determine if consensus existed among general and special education teachers on (a) the conditions and supports that are critical to including children with substantial disabilities in general education classrooms and (b) problems faced in implementing inclusive education. The data were collected in three stages. The first stage was a questionnaire sent to teachers in Pennsylvania who had experience including children with moderate to severe disabilities in general education classrooms. Through two open-ended questions, they were asked to identify critical supports for inclusion and major problems they faced when including children with disabilities. For the second stage, the same respondents were asked to rate the importance of the categories of supports and to rate the significance of the problems they faced. The results indicated that training, support from a team of professionals, and having help in the classroom were mentioned by a large portion of the respondents. The third stage involved a national sample of elementary, general education teachers responding to the open-ended questions. The respondents in the national sample (teachers who may or may not have been involved in a supported program of inclusion) identified the same three supports more often than other supports.

The metabolic cost and cognitive demand of altering natural gait have not been well studied. The purpose of this investigation was to assess three modified patterns - toe out, ipsilateral trunk lean and a medial weight shift at the foot - on the basis of 1) medial knee joint load reduction, 2) metabolic cost of performance and 3) subject perception of task difficulty.12 healthy individuals underwent 3 dimensional motion analysis and metabolic testing to assess the gait mechanics and energy expenditure of natural gait and the three experimental gait patterns, performed to a self-selected moderate degree. Walking speed was controlled. Perceived workload was assessed using the NASA Task Load Index.Trunk lean significantly reduced first peak knee adduction moment (↓32%, P0.001) as well as KAM impulse (↓35%, P0.001), but was costly in terms of energy expenditure (↑11%, P0.001) and perceived workload (↑1178%, P0.001). A moderate toe-out pattern significantly reduced the second peak knee adduction moment (↓32%, P0.001) and KAM impulse (↓14%, P=0.026), but had no effect on the first peak. Conversely, toe-out was least demanding in terms of additional energy expenditure (↑2%, P=0.001) and perceived workload (↑314%, P=0.001). Medial shift did not reduce knee adduction moment.The prioritization of joint load reduction versus additional metabolic and cognitive demands could play a substantial role in the clinical decision making process of selecting a modified gait pattern.

We evaluated the effects of teaching 13 typically developing children to use constant time delay when tutoring three of their peers who had substantial disabilities. We measured the extent to which the tutors used the constant time delay procedure correctly and the tutees' correct performance on the skills being taught. A multiple probe design across behaviors was used. The results indicated that (a) the tutors used each step of the constant time delay with a high degree of procedural fidelity; (b) the students with disabilities acquired the skills that were taught during peer tutoring; and (c) modifications of the procedure were required for 2 of the 3 students with disabilities, and the peers tutors were able to implement the modifications. Implications for practice and future research are described.

This article explores the relationship between cultural integrity, diversity, and social responsibility. The obligations and opportunities of responsible citizenship in a complex diverse society pose a difficult political issue that modern societies scarcely recognize. It is not clear, the article concludes, how large and diverse a society can become and yet remain sufficiently cohesive to behave responsibly by any meaningful standard.

The politics of the environment may not be unique, but they present some distinctive characteristics. In undertaking policy analyses and administrative strategies an appreciation of concepts, assumptions and circumstances, and underlying environmental policy issues is needed. To ignore these fundamentals is to risk superficiality in analysis, and error in findings and conclusions. Yet getting down to basics is often rejected as diversion from the goal of analysis. It deviates from a “straight to the point” approach, adds cost and time to investigation, and seldom interests practical-minded analysts. Even so, this paper will be prefaced by a concise reminder of some basic factors that make environmental policy problematic. Among these are: (1) incompatible concepts of man-nature relationships—notably conflict between perceived facts and values, (2) inadequate comprehension of the complexities of nature, (3) sectoral subdivisions of knowledge, (4) assumptions, situations and motivations in environmental politics, (5) fractionated structure of laws and administration, and (6) short-range perception of time. In addition to these conceptual factors the widely varied subject-matter of environmental politics narrows the scope of generalization for policy purposes.

Oxytocin (Oxt) and the Oxt receptor (Oxtr) are implicated in the onset of maternal behavior in a variety of species. Recently, we developed two Oxtr knockout lines: a total body knockout (Oxtr-/-) and a conditional Oxtr knockout (OxtrFB/FB) in which the Oxtr is lacking only in regions of the forebrain, allowing knockout females to potentially nurse and care for their biological offspring. In the current study, we assessed maternal behavior of postpartum OxtrFB/FB females toward their own pups and maternal behavior of virgin Oxtr-/- females toward foster pups and compared knockouts of both lines to wildtype (Oxtr+/+) littermates. We found that both Oxtr-/- and OxtrFB/FB females appear to have largely normal maternal behaviors. However, with first litters, approximately 40% of the OxtrFB/FB knockout dams experienced high pup mortality, compared to fewer than 10% of the Oxtr+/+ dams. We then went on to test whether or not this phenotype occurred in subsequent litters or when the dams were exposed to an environmental disturbance. We found that regardless of the degree of external disturbance, OxtrFB/FB females lost more pups on their first and second litters compared to wildtype females. Possible reasons for higher pup mortality in OxtrFB/FB females are discussed.

Drinking during pregnancy has been associated with learning disabilities in affected offspring. At present, there are no clinically effective pharmacotherapeutic interventions for these learning deficits. Here, we examined the effects of ABT-239, a histamine H₃ receptor antagonist, on fetal ethanol-induced fear conditioning and spatial memory deficits.Long-Evans rat dams stably consumed a mean of 2.82 g ethanol/kg during a 4-hour period each day during pregnancy. This voluntary drinking pattern produced a mean peak serum ethanol level of 84 mg/dl. Maternal weight gain, litter size and birth weights were not different between the ethanol-consuming and control groups. Female adult offspring from the control and fetal alcohol-exposed (FAE) groups received saline or 1 mg ABT-239/kg 30 minutes prior to fear conditioning training. Three days later, freezing time to the context was significantly reduced in saline-treated FAE rats compared to control. Freezing time in ABT-239-treated FAE rats was not different than that in controls. In the spatial navigation study, adult male offspring received a single injection of saline or ABT-239 30 minutes prior to 12 training trials on a fixed platform version of the Morris Water Task. All rats reached the same performance asymptote on Trials 9 to 12 on Day 1. However, 4 days later, first-trial retention of platform location was significantly worse in the saline-treated FAE rats compared control offspring. Retention by ABT-239-treated FAE rats was similar to that by controls. ABT-239's effect on spatial memory retention in FAE rats was dose dependent.These results suggest that ABT-239 administered prior to training can improve retention of acquired information by FAE offspring on more challenging versions of hippocampal-sensitive learning tasks. Further, the differential effects of ABT-239 in FAE offspring compared to controls raises questions about the impact of fetal ethanol exposure on histaminergic neurotransmission in affected offspring.

Alcohol ingestion during pregnancy, even in moderate amounts, can affect normal brain development, resulting in changes in brain functioning that can persist throughout life. Fetal alcohol spectrum disorder (FASD) is a term used to describe the wide range of clinical disorders, ranging from moderate to severe, that can occur in an individual whose mother drank alcohol during pregnancy. Investigations on the mechanisms that underlie the learning and memory impairments associated with FASD have focused on numerous processes, including glutamatergic neurotransmission. One class of glutamate receptors, the N-methyl-D-aspartate (NMDA) receptors, have received considerable attention because the levels and subcellular localization of these receptors impact the cellular processes underlying learning and memory, as well as various forms of synaptic plasticity (Gardoni et al., 2009; Tang et al., 1999; Zhang et al., 2008; Zhao et al., 2005). Several studies have found that NMDA receptors are significantly affected by prenatal alcohol exposure (see Table 1 and Costa et al., 2000a, for review). In particular, researchers have focused on NMDA receptors in the hippocampal formation, as this area of the brain has been shown to be particularly vulnerable to the effects of fetal alcohol exposure and is known to be densely populated with NMDA receptors (Berman and Hannigan, 2000). For example, prenatal alcohol exposure has been shown to decrease NMDA-sensitive glutamate binding sites in the hippocampus of 45-day-old rats (Savage et al., 1991) and alter [3H]MK-801 binding in the hippocampus of rats and guinea pigs (Abdollah and Brien, 1995; Diaz-Granados et al., 1997; Naassila and Daoust, 2002). Table 1 Summary of Literature Determining the Effects of Prenatal Alcohol Exposure on NMDA Receptor Subunit Expression NMDA receptors are ion channels that exist as heteromeric complexes composed of mandatory NR1 and modulatory NR2 (A-D) or NR3 (A, B) subunits. The NMDA receptor NR1 subunit is essential to the formation of a functional receptor (Paoletti and Neyton, 2007). Of the modulatory subunits, NR2A and NR2B are the most highly expressed forms in the adult rodent hippocampus (Al-Hallaq et al., 2007; Wenzel et al., 1997); NR3A is also present in the rodent hippocampus, but at much lower levels than NR2A and NR2B in the adult (Al-Hallaq et al., 2002; Wong et al., 2002). NMDA receptors are localized both within the synapse and extrasynaptically (Harris and Pettit, 2007; Lau and Zukin, 2007). While the overall function of an individual NMDA receptor is dependent on its subunit composition (Yashiro and Philpot, 2008), the location of the receptor governs its coupling to specific intracellular signaling pathways (Hardingham, 2006); the balance between synaptic and extrasynaptic receptor activation shapes the overall cellular response. Even though both synaptic and extrasynaptic NMDA receptors mediate Ca2+ influx, studies show that extrasynaptic receptors are mainly activated under conditions of high concentrations of NMDA (or glutamate) and mediate opposing effects on intracellular signaling pathways compared to those produced by synaptic NMDA receptors (Chandler et al., 2001; Ivanov et al., 2006; Mulholland et al., 2008). Synaptic NMDA receptors are organized and spatially restricted in large macromolecular signaling complexes called postsynaptic densities (PSDs) within the synaptic membrane (Lau and Zukin, 2007). PSD-95, a member of the membrane-associated guanylate kinase (MAGUK) family, is an anchoring and essential synaptic adapter protein, not found extrasynaptically, that targets the NMDA receptor NR2A and NR2B subunits to the PSD (Al-Hallaq et al., 2007; Chen et al., 2006; Hughes et al., 2001). Although there is evidence that the NR1 C2′ cassette contains a motif allowing it to associate with PSD-95, NR1 is generally not considered to bind to PSD-95 (Honse et al., 2003; Lim et al., 2002). This complex of PSD-95 and NMDA receptors has been implicated in the regulation of several cellular processes, including synaptic plasticity and learning and memory (Chen et al., 2006; Gardoni et al., 2009). Studies employing a variety of prenatal and neonatal alcohol exposure paradigms have yielded conflicting results regarding the effects of the exposure on NMDA receptor subunit composition (Table 1). It is also of note that most of these studies have employed relatively young animals and, in general, have not assessed the subcellular localization of the NMDA receptor subunits. It is important to determine whether such alterations in NMDA receptor subunit levels or localization exist in adult animals that were prenatally exposed to alcohol in order to determine if there is an association between these alterations and the life-long cognitive impairments observed in FASD. The current study aimed to test the hypothesis that moderate prenatal alcohol exposure is associated with differential NMDA receptor subunit expression and/or subcellular localization in adult animals.

We have synthesized phosphatidylinositol 3-phosphate from phosphatidylinositol 4-phosphate by using diisopropylcarbodiimide to promote migration of the 4-phosphate via a cyclic phosphodiester intermediate. The product was isolated by a thin-layer chromatographic method that depends on the ability of phosphatidylinositol 4-phosphate, but not phosphatidylinositol 3-phosphate, to form complexes with boric acid. The final yield of the procedure was 8% phosphatidylinositol 3-phosphate, which was approximately 80% pure. The product was shown to be phosphatidylinositol 3-phosphate by the following criteria: (i) cochromatography with an authentic standard on borate thin-layer chromatography, (ii) cochromatography of the deacylated product with glycerophosphoinositol 3-phosphate on high-performance liquid chromatography, (iii) conversion of the product to phosphatidylinositol by homogeneous phosphatidylinositol 3-phosphate 3-phosphatase, and (iv) deacylation and deglyceration of the product to a compound that comigrates with inositol 1,3-bisphosphate on high-performance liquid chromatography. The availability of mass amounts of phosphatidylinositol 3-phosphate will allow further elaboration of reactions in this recently discovered pathway of phosphatidylinositol metabolism.

Inositol-polyphosphate 3-phosphatase catalyzes the hydrolysis of the 3-position phosphate bond of inositol 1,3-bisphosphate (Ins(1,3)P2) to form inositol 1-monophosphate and inorganic phosphate (Bansal, V.S., Inhorn, R.C., and Majerus, P.W. (1987) J. Biol. Chem. 262, 9444-9447). Phosphatidylinositol 3-phosphatase catalyzes the analogous reaction utilizing phosphatidylinositol 3-phosphate (PtdIns(3)P) as substrate to form phosphatidylinositol and inorganic phosphate (Lips, D.L., and Majerus, P.W. (1989) J. Biol. Chem. 264, 19911-19915). We now demonstrate that these enzyme activities are identical. Two forms of the enzyme, designated Type I and II 3-phosphatases, were isolated from rat brain. The Type I 3-phosphatase consisted of a protein doublet that migrated at a relative Mr of 65,000 upon sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The Mr of this isoform upon size-exclusion chromatography was 110,000, suggesting that the native enzyme is a dimer. The Type II enzyme consisted of equal amounts of an Mr = 65,000 doublet and an Mr = 78,000 band upon SDS-polyacrylamide gel electrophoresis. This isoform displayed an Mr upon size-exclusion chromatography of 147,000, indicating that it is a heterodimer. The Type II 3-phosphatase catalyzed the hydrolysis of Ins(1,3)P2 with a catalytic efficiency of one-nineteenth of that measured for the Type I enzyme, whereas PtdIns(3)P was hydrolyzed by the Type II 3-phosphatase at three times the rate measured for the Type I 3-phosphatase. The Mr = 65,000 subunits of the two forms of 3-phosphatase appear to be the same based on co-migration on SDS-polyacrylamide gels and peptide maps generated with Staphylococcus aureus protease V8 and trypsin. The peptide map of the Mr = 78,000 subunit was different from that of the Mr = 65,000 subunits. Thus, we propose that the differing relative specificities of the Type I and II 3-phosphatases for Ins(1,3)P2 and PtdIns(3)P are due to the presence of the Mr = 78,000 subunit of the Type II enzyme.

Sociologist Robert Nisbet conjectured that “when the history of the twentieth century is finally written, the single most important social movement of the period will be judged to be environmentalism”; (1982, p. 10). This assessment has been reinforced by subsequent events. Environmental concern has risen to the top of political agendas in the United States and many other countries, becoming a major consideration in international relations. A major force for the globalization of environmental politics in the United States has been the growing international concern of nongovernmental environmental organizations (NGOs). Almost all of the larger environmental NGOs now have significant international programs that attempt to influence public policies. Transnational collaboration between governments and NGOs on environmental issues has become a characteristic of contemporary politics in North America and Western Europe. Global issues such as climate change, ozone depletion, transboundary air and water ...

The District of Columbia storm water management regulations established in 1988 now require mitigation of storm water run off where construction and or 5000 sq/ ft of earth disturbance occurs. As in many municipalities in the Mid-Atlantic seeking to meet requirements of the Clean Water Act (CWA), and the Water Quality Amendment in 1987 to the CWA, the District of Columbia began employing Storm Water Best Management Practices (BMPs) for the treatment of storm water run-off. BMPs have typically been end of pipe proprietary devices, underground vaults, modified manholes or filtering practices for water quality treatment and even larger under ground vaults, reinforced concrete, and metal or plastic pipes for storm water quantity control. While the district was a pioneer in the use of underground sand filters for the treatment of storm water in ultra urban settings and continues to approve and install these devices, as well as other subterranean vault and manhole BMP, the city is turning to Low Impact Development (LID) practices which have began to gain more prominence in the development community. This paper investigates publicly financed and implemented LID projects in the District of Columbia and will discuss the types of problems that have occurred and the lessons learned. Biomass mortality, aesthetics and function, as well as hydraulics and maintenance are blamed for most problems. Two LID retrofits are included in the case study and analysis focusing on a bioretention cell (including cost and monitoring data), as well as a retrofit application of various types of pervious pavers.

Oxytocin (Oxt), synthesized in magnocellular neurons of the paraventricular (PVN) and supraoptic (SON) hypothalamic nuclei for transport to and release from the posterior pituitary, is released during parturition and is essential for lactation. Lesser amounts of Oxt are made by smaller cells of the PVN and a few other forebrain nuclei and released into the central nervous system (CNS) to influence various other behaviours. In both the periphery and CNS, Oxt actions are transduced by the oxytocin receptor (Oxtr). Previously, it has been reported that Oxt(-/-) (knockout, KO) mice show a failure of milk ejection and thus are incapable of rearing their offspring. Unexpectedly, these mice have largely normal reproductive and maternal behaviours, perhaps due to compensatory mechanisms through activation of the Oxtr by vasopressin or through development. To examine the specific roles of the Oxtr during development and in particular brain areas, we created conditional Oxtr(-/-) mice in which we could control the spatial and temporal inactivation of the Oxtr. We flanked the neomycin-resistance selectable marker in an Oxtr intron with FRT sites to enable its removal using FLP recombinase. Coding sequence within exons 2 and 3 was flanked by two loxP sites enabling subsequent inactivation of the gene by targeted expression of Cre recombinase. The first Oxtr KO lines we created have either total or relatively specific forebrain elimination. The latter was achieved by crossing the conditional Oxtr line with a transgenic line in which the Camk2a promoter drives expression of Cre recombinase to significant levels beginning 21-28 days after birth, thus eliminating potential compensation for a deleted Oxtr gene during early development. This Cre-expressing line also significantly spares the main olfactory bulb reducing the potential confound of an olfactory deficit. We have investigated various behaviours, most notably social recognition, in both Oxtr KO strains (Oxtr(-/-) and Oxtr(FB/FB)).

While the importance of vasopressin (Avp) in the neuroendocrine regulation of behaviour is clear, most of Avp's effects on behaviour have been linked to its action via its 1a receptor (Avpr1a) subtype. There is, however, emerging evidence and cross-species consensus that the vasopressin 1b receptor (Avpr1b) is also important in mediating the effects of Avp on behaviour. The Avpr1b is highly expressed in the anterior pituitary where it is thought to play a role in the neuroendocrine response to stress. The Avpr1b is also prominently expressed in the pyramidal cells of the CA2 hippocampal area. Interestingly, in mice, Avpr1b mRNA within the pyramidal neurons of the CA2 field is unaffected by restraint stress or adrenalectomy. Avpr1b knockout mice (--) have provided strong, consistent evidence that the Avpr1b plays a critical role in the regulation of social behaviour. Avpr1b(-/-) mice display reduced levels of social forms of aggression, reduced social motivation and impaired social memory (including the Bruce effect). Avpr1b(-/-) mice, however, have normal main olfactory ability, spatial memory and defensive and predatory behaviours. Mice lacking a functional accessory olfactory system display many of these same behavioural deficits, suggesting that Avpr1b(-/-) mice may have a deficit in the processing, perception and/or integration of olfactory stimuli detected by the accessory olfactory system. We suggest that the role of the Avpr1b is to couple socially relevant accessory olfactory cues with the appropriate behavioural response. Furthermore, given its prominence in the CA2 field of the hippocampus, we hypothesize that Avpr1b may be important for the formation or recall of memories that have an olfactory-based social component.