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Visceral hypersensitivity is the leading complaint of functional bowel disorders. Central sensitization mediated by glutamate receptor activation is implicated in pathophysiology of visceral pain. The glial glutamate transporter EAAT2 is the principal mediator of glutamate clearance to terminate glutamate-mediated responses. Transgenic mice overexpressing human EAAT2 (EAAT2 mice), which exhibited a twofold enhanced glutamate uptake, showed 39% less writhing response to intraperitoneal acetic acid than nontransgenic littermates. Moreover, EAAT2 transgenic mice showed a 53-64% reduction in visceromotor response (VMR) to colorectal distension (CRD) in assessments of the response to graded increase in pressures. Corroborating the involvement of enhanced glutamate uptake, wild-type mice treated for 1 wk with ceftriaxone, an EAAT2 expression activator, showed a 49-70% reduction in VMR to CRD. Moreover, systemic pretreatment with the selective EAAT2 transporter blocker dihydrokainate reversed the ceftriaxone-blunted nociceptive response to CRD. However, the enhanced VMR to CRD produced by intracolonic ethanol was not significantly attenuated by 1-wk ceftriaxone pretreatment. The data suggest that enhanced glutamate uptake provides protective effects against colonic distension-induced nociception and represents an exciting new mechanistic approach leading to better therapeutic options to visceral pain disorders.

Objective: To examine the impact of a decision aid (DA) designed to promote informed decision making for screening with the prostate-specific antigen (PSA) test and to test a theoretical model of factors influencing decisional conflict., Design: Structural equation modeling examined pathways between DA exposure, knowledge, schema, prostate cancer risk perceptions, decisional anxiety, and decisional conflict. Sample participants included 200 men from the general population (exclusive of African Americans) and 200 African American men. Half of the men in each subsample were randomly assigned to receive the DA., Main Outcome Measures: Decisional conflict regarding prostate cancer screening., Results: The DA influences level of decisional conflict by increasing patient knowledge. This effect of knowledge on decisional conflict is indirect, however, through an association with greater perceived risk and lower decisional anxiety. Also, positive PSA schema was associated with lower decisional anxiety and decisional conflict. It is important that exposure to the DA had no impact on PSA schema., Conclusion: Schemas about testing must be considered in developing messages about the risks and benefits of testing. If schemas are counter to message content, mechanisms for modifying schemas must be incorporated into interventions.

This article examines data for 8,484 transition-aged youth (TAY) in different age groups who received services in 45 federally funded systems of care between 1997 and 2006. Data from the national evaluation of these systems of care were used to compare descriptive and clinical characteristics at intake of TAY aged 14-15, 16-17, and 18 years, and service use and outcomes of TAY aged 14-15 and 16-17 at 6 and 12 months after system of care intake. Few studies have examined outcomes of TAY. The large national evaluation database provides a unique opportunity to examine outcomes for TAY in relation to increases in age. Results revealed differences in severity and type of behavioral and emotional problems, living situations, access to Medicaid, service use, and outcomes among younger and older youth. Findings support the need to enhance access to services for older TAY and to customize services to the unique needs of each age group.

An emerging theme in the study of the pathophysiology of chronic and persistent pain is the role of pro-oxidant substances. Reactive oxygen species (ROS) have been implicated in contributing to and/or maintaining conditions of chronic pain. Recent pre-clinical reports suggest that antioxidants are effective analgesics in neuropathic and inflammatory pain models. The present study extends this work by examining the effect of three antioxidants on tissue injury-induced nociception. C57BL6 mice (20-25 g) were pretreated with either phenyl-N-tert-butylnitrone (PBN; 50 mg/kg, i.p.), 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxy (TEMPOL; 200 or 50 mg/kg, i.p.), N-acetyl-L-cysteine (NAC; 200 or 100mg/kg, i.p.), or vehicle (0.5 ml/100 g), 5 min before intraplantar formalin (10%, 20 microl) injection. Nociceptive responding, indicated by licking or biting the affected hindlimb, was quantified for 30 min after formalin injection. Each drug was effective in attenuating two or more phases (acute, quiescent, and tonic) of the formalin response. To assess putative site of action, intrathecal TEMPOL (380 nmol/5 microl, i.t.) was given 5 min before intraplantar formalin. Intrathecal TEMPOL produced a 83% reduction in nociceptive responding in the tonic phase, but no significant attenuation of the acute phase response. To confirm that the antioxidant property of intrathecal TEMPOL was responsible for its analgesic effect on the formalin-induced pain response, intrathecal TEMPOL was coadministered with the free radical donor tert-butylhydroperoxide (tert-BuOOH). Tert-BuOOH coadminstration reversed the TEMPOL-induced analgesia in the tonic intraplantar formalin response reduction. The data suggest that pro-oxidant species may be important mediators of tissue injury-induced algesia in rodents, and that a spinal site of action is implicated in the tonic response.

Purpose: Radiation is considered the standard treatment for locally advanced (T3 and T4) prostate cancer but cure with radiation alone is infrequent. Studies have shown that adding androgen ablation improves the results but there is still much room for improvement. We performed a phase II multi-institutional study to explore the feasibility of concomitant chemoradiotherapy., Materials and Methods: Eligible patients had prostate cancer with clinical evidence of invasion through the prostatic capsule or into the seminal vesicles without evidence of nodal or distant metastasis. Prior prostatectomy was not allowed and patients could not be candidates for surgical resection due to medical reasons or refusal of surgery. Radiation consisted of 7,020 cGy in 39 fractions. Continuous infusion 5-fluorouracil at a dose of 200 mg/m2 daily was started on day 1 and continued 7 days weekly until the last day of radiation., Results: All 30 eligible patients were evaluated for toxicity. Diarrhea was the most common toxicity with grade 3 and 4 diarrhea in 2 and 1 patients, respectively. The only other grade 4 toxicity was hemorrhagic cystitis in 1 patient. There was 1 incident each of grade 3 stomatitis, congestive heart failure, edema, proctitis and hematuria. No patient with grade 3 or 4 toxicity required treatment delay. Ten patients (33%) achieved a negative biopsy and 13 (43%) achieved prostate specific antigen less than 1.0 ng/ml. Six patients (20%) achieved a complete response, defined as negative biopsy and prostate specific antigen less than 1.0 (95% CI 8 to 39). Patients without any biopsies or without prostate specific antigen followup were assumed to be nonresponders., Conclusions: Toxicity was acceptable. The modest response rate indicates that better chemotherapy that improves local and systemic failure is necessary to improve the results. This study confirms the feasibility of a combined chemoradiotherapy approach.

There are three known high-affinity targets for cocaine: the dopamine transporter (DAT), the serotonin transporter (SERT), and the norepinephrine transporter (NET). Decades of studies support the dopamine (DA) hypothesis that the blockade of DAT and the subsequent increase in extracellular DA primarily mediate cocaine reward and reinforcement. Contrary to expectations, DAT knockout (DAT-KO) mice and SERT or NET knockout mice still self-administer cocaine and/or display conditioned place preference (CPP) to cocaine, which led to the reevaluation of the DA hypothesis and the proposal of redundant reward pathways. To study the role of DAT in cocaine reward, we have generated a knockin mouse line carrying a functional DAT that is insensitive to cocaine. In these mice, cocaine suppressed locomotor activity, did not elevate extracellular DA in the nucleus accumbens, and did not produce reward as measured by CPP. This result suggests that blockade of DAT is necessary for cocaine reward in mice with a functional DAT. This mouse model is unique in that it is specifically designed to differentiate the role of DAT from the roles of NET and SERT in cocaine-induced biochemical and behavioral effects.

Glutamate is a neurotransmitter critical for spinal excitatory synaptic transmission and for generation and maintenance of spinal states of pain hypersensitivity via activation of glutamate receptors. Understanding the regulation of synaptically and non-synaptically released glutamate associated with pathological pain is important in exploring novel molecular mechanisms and developing therapeutic strategies of pathological pain. The glutamate transporter system is the primary mechanism for the inactivation of synaptically released glutamate and the maintenance of glutamate homeostasis. Recent studies demonstrated that spinal glutamate transporter inhibition relieved pathological pain, suggesting that the spinal glutamate transporter might serve as a therapeutic target for treatment of pathological pain. However, the exact function of glutamate transporter in pathological pain is not completely understood. This report will review the evidence for the role of the spinal glutamate transporter during normal sensory transmission and pathological pain conditions and discuss potential mechanisms by which spinal glutamate transporter is involved in pathological pain.

Glutamate is a major excitatory neurotransmitter in primary afferent terminals and is critical for normal spinal excitatory synaptic transmission. However, little is known about the regulation of synaptically released glutamate in the spinal cord under physiologic conditions. The sodium-dependent, high-affinity glutamate transporters are the primary mechanism for the clearance of synaptically released glutamate. In the present study, we found that intrathecal injection of glutamate transporter blockers DL-threo-beta-benzyloxyaspartate (TBOA) and dihydrokainate produced significant and dose-dependent spontaneous nociceptive behaviors, such as licking, shaking, and caudally directed biting, phenomena similar to the behaviors caused by intrathecal glutamate receptor agonists. Intrathecal TBOA also led to remarkable hypersensitivity in response to thermal and mechanical stimuli. These behavioral responses could be significantly blocked by intrathecal injection of the NMDA receptor antagonists MK-801 and AP-5, the non-NMDA receptor antagonist CNQX or the nitric oxide synthase inhibitor L-NAME. In vivo microdialysis analysis showed short-term elevation of extracellular glutamate concentration in the spinal cord after intrathecal injection of TBOA. Furthermore, topical application of TBOA on the dorsal surface of the spinal cord resulted in a significant elevation of extracellular glutamate concentration demonstrated by in vivo glutamate voltametry. The present study indicates that defective spinal glutamate uptake caused by inhibition of glutamate transporters leads to excessive glutamate accumulation in the spinal cord. The latter results in persistent over-activation of synaptic glutamate receptors, producing spontaneous nociceptive behaviors and sensory hypersensitivity. Our results suggest that glutamate uptake through spinal glutamate transporters is critical for maintaining normal sensory transmission under physiologic conditions.

Alteration of glutamatergic (GLU) neurotransmission within the spinal cord contributes to hyperalgesic and allodynic responses following nerve injury. In particular, changes in expression and efficacy of glutamate transporters have been reported. Excitatory, pain transmitting primary afferent neurons utilizing glutamate as an excitatory neurotransmitter project to both superficial (I-II) and deep (III-V) laminae of the dorsal horn. These experiments were designed to examine changes in glutamate uptake occurring concomitantly within the spinal deep dorsal and ventral horn in situ after experimentally induced neuropathic pain. In vivo voltammetry, using microelectrode arrays configured for enzyme-based detection of GLU were employed. Sprague-Dawley rats had either sham surgery or tight ligation of L5 and L6 spinal nerves (SNL). Four to six weeks later, the L4-L6 spinal cord of chloral hydrate-anesthetized animals was exposed, and ceramic-based glutamate microelectrodes equipped with glass micropipettes 50 microm from the recording surfaces were placed stereotaxically at sites within the spinal cord. Pressure ejection of GLU into the ipsilateral L5-L6 spinal cord resulted in a 72% reduction of GLU uptake in SNL rats compared to sham controls in the ipsilateral L5-L6 deep dorsal horn and a 96% reduction in the ventral horn. In contrast, in the same animals, the contralateral L5-L6 or the ipsilateral L4 spinal cord showed no change in glutamate uptake. The data suggest that spinal nerve ligation produced attenuated glutamate uptake activity extending into the deep dorsal and ventral horn. The study suggests that plasticity related to spinal nerve injury produces widespread alteration in glutamate transporter function that may contribute to the pathophysiology of neuropathic pain.

Peripheral nerve injury leads to the activation of spinal cord astrocytes, which contribute to maintaining neuropathic (NP) pain behavior. Fibroblast growth factor-2 (FGF-2), a neurotrophic and gliogenic factor, is upregulated by spinal cord astrocytes in response to ligation of spinal nerves L5 and L6 (spinal nerve ligation [SpNL]). To evaluate the contribution of spinal astroglial FGF-2 to mechanical allodynia following SpNL, neutralizing antibodies to FGF-2 were injected intrathecally. Administration of 18 microg of anti-FGF-2 antibodies attenuated mechanical allodynia at day 21 after SpNL and reduced FGF-2 and glial acidic fibrillary protein mRNA expression and immunoreactivity in the L5 spinal cord segment of rats with SpNL. These results suggest that endogenous astroglial FGF-2 contributes to maintaining NP tactile allodynia associated with reactivity of spinal cord astrocytes and that inhibition of spinal FGF-2 ameliorates NP pain signs.

This article explores the rates of co-occurring disorders in two large federally-funded programs that target youth. In the mental health treatment system, the Substance Abuse and Mental Health Services Administration's (SAMHSA) Center for Mental Health Services (CMHS) supports the Comprehensive Community Mental Health Services for Children and Their Families Program. SAMHSA's Center for Substance Abuse Treatment (CSAT) supports a number of grant programs providing substance abuse treatment for adolescents. The data from these programs underscores the need for the use of systematic, validated, biopsychosocial assessment instruments for all youth entering either the substance abuse or mental health treatment systems. The current evidence base for models of co-occurring treatment for youth is discussed and recommendations made for future activity related to adolescent co-occurring treatment.

Neuropathic pain involves co-regulation of many genes and their translational products in both peripheral and central nervous system. We used proteomics approaches to investigate expressional changes in cytosolic protein levels in rat brainstem tissues following ligation of lumbar 5 and 6 (L5, L6) spinal nerves, which generates a model of peripheral neuropathic pain (NP). Proteins from brainstem tissue homogenates of NP and SHAM animals were fractionated by two-dimensional (2-DE) gel electrophoresis to produce a high-resolution map of the brainstem soluble proteins. Proteins showing altered expression levels between NP and SHAM were selected. Isolated proteins were in-gel trypsin-digested and the resulting peptides were analyzed by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry. Using the mass spectrometric data, we were able to identify 17 proteins of interest through searches of the Swiss-Prot and NCBi nonredundant protein sequence database. Several of the identified proteins, including fatty acid binding protein-brain (FABP-B), major histocompatibility complex (MHC) class 1, T-cell receptor (TCR) alpha chain, and interleukin-1 (IL-1), showed significantly higher levels in the NP rat brainstem. Proteomic analysis has identified several proteins with differential expression levels in NP as compared to SHAM. However, the function of the proteins identified is postulated; therefore, further experiments are required to determine the true role of each protein in NP.

Latent class analyses were used to analyze data from a sample of children participating in the national evaluation of the Comprehensive Communities Mental Health Services for Children and Their Families Program (N = 6786). Lifetime risk experiences of the child were analyzed to identify 4 classes of boys and girls with similar risk patterns. While low-risk, status-offense, abuse, and high-risk classes were identified for both boys and girls, there were nearly half the number of girls in the low-risk class, almost as many in the status-offense class, twice as many in the abuse class, and more than 3 three times as many in the high-risk class as there were boys. These findings suggest that there are specific groups of children entering services who differ as a function of their lifetime risk exposure. In addition, the relationship between class membership and child functioning, and class membership and family lifetime risk experiences. Understanding these differences provides critical information to the service planning process. In addition, it may result in immediate improvement in the triage of children into services and a better understanding of their behaviors during and after treatment.

In peripheral neuropathy (PN), dorsal column (DC) fibers that synapse in the nucleus gracilis (NuGr) mediate expression of mechanical allodynia and have increased expression of brain-derived neurotrophic factor (BDNF). Neurotrophins (NTs) are implicated in pathology or repair in PN. To assess NTs in the NuGr in PN, mRNA expression of BDNF, nerve growth factor (NGF), and NT receptors TrkA, TrkB, and p75 was determined 1 week after ligation of L5 and L6 spinal nerves (SNL). Laser capture microdissection was used to collect NuGr tissue followed by reverse-transcription (RT)-PCR. TrkA, TrkB, and NGF mRNA levels decreased, whereas p75 mRNA increased, in ipsilateral SNL NuGr compared with SHAM; BDNF was undetectable. Decreased Trk mRNA may result in decreased NT activity in the NuGr. The p75 receptor influences Trk activity and cell survival, thus its role in PN warrants further investigation.

Spinal nerve ligation results in dramatic changes in spinal cord primary C-afferent fibers, which include atrophy with an accompanied decrease in calcitonin-gene-related peptide (CGRP). These changes parallel the activation of astrocytes, which have been implicated in the ensuing neuropathic pain states. As part of an effort to elucidate the role of the downstream effectors of astrocyte reactivity in the context of allodynia, the expression of fibroblast growth factor-2 (FGF-2) was examined following tight ligation of L5 and L6 spinal nerves. FGF-2 is a pleiotropic cytokine that is synthesized and secreted by neurons and astrocytes. FGF-2 immunoreactivity was increased in ipsilateral dorsal horn reactive astrocytes at 1 and 3 weeks following nerve ligation. Semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) of laser-captured dorsal spinal cord sections revealed an increase in FGF-2 mRNA in the dorsal horn ipsilateral to nerve injury compared to contralateral and SHAM. Furthermore, an increase in FGF-2 mRNA in ispilateral dorsal root ganglia (DRG) was seen by in situ hybridization. These results demonstrate that, in response to ligation-induced injury of sensory neurons, FGF-2 is upregulated in both DRG neurons and in spinal cord astrocytes, suggesting neurotrophic functions of this growth factor following peripheral nerve lesion and possibly in astrocyte-related maintenance of pain states.

Drugs that inhibit reuptake of monoamines are frequently used to treat pain syndromes, e.g. neuropathy or fibromyalgia, where mechanical allodynia is present. Several lines of evidence suggest the involvement of supraspinal sites of action of these drugs. However, a direct study of supraspinal serotonin (5-HT) or norepinephrine (NE) release in an animal model in which allodynia is expressed, e.g. neuropathy, has not been done. The ventrobasal (VB) thalamus and the hypothalamus are major supraspinal projection regions for spinal neurons that transmit nociceptive information and are innervated by monoaminergic fibers. This study determined if peripheral neuropathy would induce changes in extracellular monoamines in VB thalamus and hypothalamus. Male Sprague-Dawley rats had spinal nerve roots L5 and L6 tightly ligated (neuropathic rats; NP) or sham (SHAM) surgery; contralateral and ipsilateral VB thalamus and contralateral hypothalamus were dialyzed with modified artificial cerebral spinal fluid (aCSF), with and without fluoxetine. NP rats had significantly decreased 5-HT content in dialysates of the contralateral VB thalamus compared with SHAM rats with (82% decrease) or without (63% decrease) fluoxetine in the perfusion medium over the 180 min of the study. There were no differences in the ipsilateral VB thalamus. In contrast, release of 5-HT was unchanged in the hypothalamic dialysates of SHAM vs. NP rats. NE release was not different in dialysates of either the VB thalamus or hypothalamus of SHAM vs. NP rats. Synthesis of 5-HT, as assessed by accumulation of 5-hydroxytrytophan after treatment with an L-amino acid decarboxylase inhibitor, was not different between NP and SHAM rats in VB thalamic and hypothalamic brain tissue. This study is the first to demonstrate changes in monoamine release supraspinally in NP rats. The differential effect between VB thalamus and hypothalamus suggests that a terminal field change may be involved. Putative mechanisms for mediating this change include alterations of GABA-ergic systems and/or plasticity related to alterations in N-methyl-D-aspartate receptor activation and nitric oxide release related to afferent hyperactivity induced by neuropathic pain., (Copyright 2002 International Association for the Study of Pain)

A benefit-cost analysis of specialty residential treatment (Specialty) and standard residential treatment (Standard) was conducted on a sample of pregnant and parenting substance abusers from Arkansas. Economic benefits were derived from client self-reported information at treatment entry and at 6-month postdischarge with the use of an augmented version of the Addiction Severity Index (ASI). The average cost of treatment in Specialty programs was US dollars 8035 versus US dollars 1467 for Standard residential treatment. Average net benefits (benefit-cost ratios) were estimated to be US dollars 17144 (3.1) for Specialty and US dollars 8090 (6.5) for Standard. The main policy implication of this research is that investment in Specialty residential treatment for pregnant and parenting substance-abusing women appears to be economically justified, but future evaluations should analyze larger and more comparable samples to improve power and precision in the benefit-cost statistics.

Methiothepin, a nonselective 5-HT receptor antagonist was utilized to explore the 5-HT modulation of dorsal vagal complex-TRH (thyrotropin releasing hormone) analogue stimulated gastric functional parameters. Intracisternal methiothepin pretreatment (200, 0.1 nmol) produced significant inhibition (70%, 44%, respectively) of the TRH analogue [p-Glu-His-(3,3'-dimethyl)-Pro NH2; RX 77368 (12 pmol)]-induced gastric acid output compared to vehicle pretreatment. Intracisternal pretreatment with methysergide (nonspecific 5-HT receptor antagonist) or combined cyanopindolol (5-HT(1A and 1B) receptor antagonist)+ritanserin (receptor antagonist of the 5-HT(2) family) did not alter the dorsal vagal complex-RX 77368 response. Unilateral dorsal vagal complex pretreatment with methiothepin (50 nmol/50 nl) attenuated ipsilateral dorsal vagal complex-TRH analog (12 pmol) induced gastric secretory response by 57%. The gastric secretagogue response to stimulation of the raphe obscurus (mediated by TRH release into the dorsal vagal complex) was inhibited 50% by pretreatment with intracisternal dorsal medullary methiothepin (0.1 nmol/10 microl). Intracisternal methiothepin (200 nmol/20 microl) also attenuated (a) dorsal vagal complex-glutamate (60 nmol/30 nl) stimulated gastric acid secretion and (b) gastric motility stimulated by dorsal vagal complex-RX 77368 (12 pmol/30 nl). The data suggest that other properties of methiothepin, alone or in addition to its 5-HT receptor antagonist effect, mediate its inhibitory actions at the dorsal vagal complex.

Intrathecal thyrotropin-releasing hormone (TRH) potently inhibits penile erection at all doses (100, 500, 1000 or 5000 pmol) tested so far. Since the serotonin receptor antagonist methiothepin (MT) inhibits TRH responses in other systems, this study tested the hypothesis that MT-sensitive receptors mediate the effect of TRH on penile erection in rats. When compared to controls, the highest doses of IT TRH (0, 10 or 500 pmol) or MT (5 or 50 nmol) significantly altered penile reflex latency. When coadministered (50 nmol MT/500 pmol TRH), the effect of TRH was reversed, suggesting that the high dose of MT antagonized the inhibitory actions of TRH. The low dose of MT (5 nmol) did not block the 500 pmol TRH inhibition of reflex latency. These data further suggest that MT sensitive receptors are important in (1) mediating normal penile reflexes and (2) mediating the inhibitory response to TRH.

Serotonin (5-HT) interacts with thyrotropin-releasing hormone (TRH) at the dorsal vagal complex (DVC) to augment TRH-induced stimulation of gastric acid secretion. To investigate the 5-HT receptor family involved in the augmentation response, prototypical 5-HT receptor-selective agonists (146 pmol) were coinjected with the TRH analog RX-77368 (RX; 12 pmol) into the rat DVC in a 30-nl volume. The DVC coordinates were 0.2 mm anterior, 0.2 mm right, 0.6 mm ventral with respect to the calamus scriptorius. Coinjection of RX with the 5-HT agonists 5-carboxyamidotryptamine (5-CT) or (+/-)-1-(4-iodo-2,5-dimethoxyphenyl)-2-aminopropane hydrochloride (DOI; 5-HT2 agonist) produced a 183 or 103% increase in gastric acid output compared with the RX injection alone. In contrast, coinjection of 2-methyl-5-HT (5-HT3 agonist) with RX produced no effect on RX-induced increase in gastric acid secretion. Moreover, coinjection of SC-53116 (5-HT4 agonist) decreased the gastric acid output by 45% compared with the RX response itself. Examination of the RX/5-HT agonist coinjection response in more rostral regions of the DVC using the same doses (5-CT/RX or DOI/RX) revealed that only 5-CT was effective in producing the augmented response to TRH analog. The results suggest that activation of 5-CT- or DOI-sensitive receptors augments, and of 5-HT4 receptors inhibits, the gastric acid response to TRH analog injected into the DVC. Thus the integrated response to several serotonin receptor subtypes may mediate changes to the TRH response induced by 5-HT at the DVC.

The pancreatic polypeptide family of hormones and neurotransmitters including pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY) are emerging as potent central regulators of gastric function. There is, however, considerable debate concerning the mechanisms and even the direction of effects mediated by these peptides. Good evidence exists showing that PYY is the 'enterogastrone' released by the ileum after feeding which acts on vagal reflex control circuits to reduce gastric motility (i.e. the 'ileal brake'). However, equally convincing evidence is available to suggest that PYY and its close structural relative NPY may act in the same region of the brain to increase gastric motility through vagal mechanisms. We hypothesize that the confounding observations are due to agonist effects on two different receptor types-Y1 and Y2, which are both present in the dorsal vagal complex (DVC) but may be accessed differentially by peripheral humoral (PYY) vs central (NPY) pathways. In our initial approach to this problem, we studied the effects of NPY, PYY, Y1 and Y2 agonists microinjected into the DVC on gastric motility in the stimulated (by central thyrotropin-releasing hormone (TRH) and basal conditions. Our results show that Y2 agonist applied to the DVC during conditions of TRH-stimulated gastric motility mimicked the suppressive effects of PYY applied under the same conditions. Under basal conditions, Y2 agonist has no effect on motility. The DVC effect of the Y1 agonist is the opposite; Y1 agonist has no further effect to stimulate gastric motility in the TRH stimulated condition while Y1 agonist strongly stimulates motility from the basal condition. The effects of NPY depend upon the condition of study. Under TRH stimulation (maximal motility), NPY in the DVC reduces (but does not completely suppress) gastric motility while in the basal state, NPY is a strong activator of motility. These results are discussed in terms of the possible differential localization of Y1 vs Y2 receptors within the DVC and in terms of recent findings suggesting that PYY is rapidly converted to a Y2 agonist by a ubiquitous dipeptidyl aminopeptidase (DAP-IV).

1. The purpose of this study was to examine the change in gastric acid output and gastric erosion formation produced by inducing gastric enterochromaffin-like (ECL) cell hyperplasia in female rats. 2. Rats were treated with vehicle or ranitidine (1,200 mumol/kg/day x 4 wks) administered via SC Alzet minipumps. Experiments were performed 24 hours after removing the minipump, when the inhibitory effect of ranitidine on gastric acid secretion had been lost. 3. Basal gastric acid secretion was 7-fold higher in chronic ranitidine animals than in sham control. 4. Both total and net gastric acid secretions stimulated by carbachol/pentagastrin infusion or histamine injection were significantly higher in the chronic ranitidine animals than in controls. 5. By contrast, intracisternal injection of the chemical vagal stimulant RX77368 (100 ng) resulted in no net increase in acid output of recovered ranitidine-pretreated group. 6. No significant changes in gastric erosions produced experimentally by cold exposure plus restraint or indomethacin pretreatment were noted in recovered chronic ranitidine animals compared to sham controls. 7. These findings suggest that achlorhydria-induced ECL cell hyperplasia augments both basal and stimulated gastric acid secretory function. The histamine results implicate an enhanced parietal cell mass, upregulation of H2 receptors, and/or second-messenger events at the parietal cell as the mechanism for the enhanced gastric secretory response.

Despite many reports that serotonin (5-HT) inhibits gastric acid output, the role and mechanism of action of endogenous 5-HT to modulate gastric secretion remain unclear. Vagal stimulation enhanced the basal rate of 5-HT release into both the gastric lumen (600%) and the portal circulation (265%) of the rat. The peak rate of 5-HT release into the portal circulation was 1,000-fold higher that luminal release (12 micrograms/min and 1.2 ng/min, respectively). To elucidate site(s) of action of 5-HT to inhibit acid secretion, several approaches were taken. Intraluminal perfusion of exogenous 5-HT to encompass enhanced levels seen after vagal stimulation did not reduce gastric acid output. In contrast, administration of systemic 5-HT, which raised portal venous 5-HT to similar levels as vagal stimulation, had a marked antisecretory effect. Chemical or surgical ablation of enteric or sympathetic nerves innervating the stomach did not attenuate the inhibitory effect of exogenous 5-HT on gastric acid output. The antisecretory effect of systemic 5-HT was insensitive to pretreatment with piroxicam, doxantrazole, close gastric intra-arterial sodium nitroprusside, somatostatin monoclonal antibody, or bilateral adrenalectomy. The results suggest that 5-HT is released from endogenous stores into the portal circulation in sufficient quantities after vagal stimulation to alter gastric physiology and that its action is independent of the autonomic nervous system, gastric mucosal prostaglandins or somatostatin, mucosal mast cell or adrenal constituents, or changes in gastric mucosal blood flow.

Convergent evidence suggests that thyrotropin-releasing hormone (TRH) is a principal regulator of several vagally mediated gastric responses. Serotonin (5-HT) interacts with TRH in the dorsal vagal complex (DVC) to augment gastric acid secretory responses. This study investigated the ability of 5-HT to alter other gastric responses mediated by TRH administration into the DVC. Co-injection of 5-HT (7.9 pmol) and the TRH analogue RX-77368 (0.66 pmol) produced a 117% enhancement in 1-h gastric acid output compared with rats treated with RX-77368 (0.66 pmol) alone into the DVC. In contrast, coadministration of RX-77368 (4 pmol) with various doses of 5-HT (0.0048-480 pmol) was ineffective in significantly altering stimulation of gastric antral motility produced by RX-77368 (4 pmol) alone. The effect of a lower dose of DVC RX-77368 (0.66 pmol) on gastric motility was also not changed by 5-HT coadministration. Moreover, the cytoprotective effect of DVC RX-77368 (1.5 pmol) on oral ethanol-induced gastric mucosal lesions was reversed by 5-HT coadministration (54 or 18 pmol). The results suggest that activation of 5-HT receptors in the DVC can augment, not affect, and attenuate DVC TRH analogue-stimulated gastric acid secretion, antral motility, and cytoprotection, respectively.

Clinical and experimental observations in humans and animals have shown that different cardiac adaptations occur in response to different types of hemodynamic overload. However, very little is known about how different hemodynamic loads lead to these different cardiac adaptations. Accordingly, we studied the acute response of ejecting isolated rabbit hearts to independently varied systolic and diastolic mechanical loads at constant coronary perfusion pressure. We studied the combined effects of low end-diastolic volume (EDV) and low systolic ejection pressure (Pej), compared to low EDV and high Pej, high EDU and low Pej, and high EDV and high Pej, on the expression of c-fos, c-jun, and egr-1. Further, although we did not seek to clarify the role of these immediate-early genes in cardiac hypertrophy, we hypothesized that they should not all respond in the same manner to these different mechanical loads. In these ejecting hearts we found that the expression of these immediate-early genes did not all respond alike to the different mechanical loads: both c-fos and egr-1 were strongly induced at both 30 and 60 min. However, at 30 min only c-fos depended on the level of EDV (P = 0.01). Neither c-fos nor egr-1 was influenced by EDV at 60 min. The expression of c-jun was largely insensitive to all loading conditions. We conclude that EDV, independent of Pej, influences the pattern and time course of expression of some immediately-early genes and that these different immediate-early genes do not respond in parallel to changes in cardiac loading.

Based on the reports of substantial improvement in the response rate w ith the addition of tamoxifen to a multiagent chemotherapy regimen for metastatic melanoma, Southwest Oncology Group (SWOG)-8921 was initiated. A prior regimen (SWOG-8804) of dacarbazine (DTIC) 750 mg/m(2) i.v. day 1 and cisplatin 100 mg/m(2) day 1 repeated every 3 weeks produced a 13% response rate in patients with metastatic melanoma without brain metastasis. SWOG-8921 using identical chemotherapy and schedule added tamoxifen 10 mg twice daily. There were 55 eligible patients registered, median age 52, with 37 men and 18 women. Fifty (91%) patients had evidence of visceral metastasis at registration. There were 10 responders (2 complete and 8 partial responses) for an 18% response rate (95% CI, 9-31%). The response rate in women was 28% (95% CI, 10-53%; in men, 14% (95% CI, 5-29%). Tamoxifen has produced a small increase in the response rate when added to the present combination and schedule of chemotherapy. Further Phase III trials will be necessary to assess whether there is a statistical advantage to the use of tamoxifen when combined with chemotherapy and whether there are statistical differences between men and women.

Peptide YY (PYY) has been shown to effectively regulate gastrointestinal function when administered intravenously. In the present study, the effect of intracisternal (i.c.) injection of rat PYY on the rate of gastric emptying was investigated in conscious animals. Vehicle, bombesin or different doses of PYY was given i.c. after animals had been given an oral liquid meal. A dose-dependent inhibition of gastric emptying was observed following the injection of PYY (400 fmol, 40 fmol and 40 amol; in 10 microliters) into the cisterna magna. The 400 fmol dose of PYY produced an inhibition of similar magnitude as that caused by bombesin (600 fmol in 10 microliters). Furthermore, subdiaphragmatic vagotomy resulted in an elimination of the inhibitory PYY effect on gastric emptying, suggesting that PYY action to inhibit gastric function depends on intact vagal pathways.

Serotonin interacts with TRH at the dorsal vagal complex (DVC) to augment gastric functional parameters. To ascertain physiologic relevance, patterns of stimulated release at the terminal field were characterized. Stimulation of the nucleus raphe obscurus (nRO) by kainic acid (423 pmol/10 nol) produced marked release of serotonin into dorsal medullary dialysates containing the DVC in freely fed, but no 24-h fasted rats. Probe infusion of kynurenic acid (1 mM), but not acute bilateral cervical vagotomy attenuated nRO-stimulated serotonin release in fed animals. The results suggest that the fed state facilitates serotonin release into the dorsal medulla by a mechanism mediated by activation of excitatory amino acid receptors in the dorsal medulla. Enhanced serotonergic neurotransmission at the DVC may comprise a heretofore unrecognized component of the integrated vago-vagal response to a meal.

Serotonin (5-hydroxytryptamine, 5-HT) is a neuroendocrine component of the gastrointestinal tract. 5-HT1A receptors exist both in the brain and have been demonstrated autoradiographically in high density in the rat stomach. However, the physiologic role of 5-HT1A receptors in modulating gastric function is not known. The effect of the selective 5-HT1A receptor agonist, (+/-)-8-hydroxy-2-(n-dipropylamino)tetralin (8-OH-DPAT), on gastric acid secretory function was compared to 5-HT in acute, urethane-anesthetized gastric-fistulated rats during pentagastrin infusion. 5-HT inhibited, but 8-OH-DPAT stimulated, gastric acid secretion in a dose-dependent manner. Bilateral cervical vagotomy or celiac ganglionectomy did not reverse the effect of 8-OH-DPAT on acid secretion. However, the enhancement of acid by 8-OH-DPAT was attenuated by acute adrenalectomy or close intra-arterial administration of spiperone, but not idazoxan. Thus, the data suggest that the selective 5-HT1A receptor agonist 8-OH-DPAT may augment gastric secretory function via an adrenal-dependent mechanism.

Pancreatic polypeptide (PP) has been shown to alter gastrointestinal functions, including increased gastric acid secretion and motility following brain stem injections of PP. The present study investigated the effect of an intracisternal injection of PP on the rate of gastric emptying. Additionally, the efficacy of the rat and bovine forms of the peptide was compared. Rats anesthetized with ether received an intracisternal injection of rat PP, bovine PP, or vehicle and, upon regaining consciousness, were fed a liquid test "meal." Intracisternal rat PP produced a marked enhancement in gastric emptying compared with control animals. Bovine PP, at doses equimolar to or three times greater than the effective rat PP dose, produced no change in gastric emptying. Pretreatment with systemic atropine prior to central injection of rat PP eliminated the stimulation of emptying, suggesting that PP acts through a cholinergic mechanism. When equimolar doses of rat or bovine PP were microinjected directly into the dorsal vagal complex, the region containing PP receptors, both were capable of stimulating antral motility. The response to bovine PP, however, was delayed and reduced compared with that seen following rat PP. The results suggest that rat PP strongly stimulates gastric emptying in rats and that bovine PP, depending on the route of administration, is either ineffectual or a weaker agonist for central PP receptors.

5-Hydroxytryptamine (serotonin, 5-HT) is released from the gastrointestinal tract by vagal stimulation. This biogenic amine produces many alterations in gastric functional parameters, including inhibition of gastric acid secretion. This study was designed to characterize the 5-HT receptor subtype modulating gastric acid secretion. In urethane-anesthetized acute gastric fistula rats, systemic 5-HT (3.5 mumol/kg i.v.) inhibited acid output stimulated by pentagastrin infusion by 58%. Close gastric intra-arterial (i.a.) injection of methysergide, methiothepin, metergoline or spiperone but not tropisetron, renzapride or ritanserin was effective in reversing 5-HT-induced inhibition of acid secretion. Close i.a. administration of the potent 5-HT1A/1B antagonist 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl]piperazine displayed partial agonist properties in this model, but did not antagonize 5-HT-induced inhibition of acid output. In a study of 5-HT agonists given close i.a. to the gastric circulation, 5-HT (0.88 mumol/kg) inhibited acid secretion by 48%. A 3-fold higher dose (2.6 mumol/kg) of the general 5-HT1 agonist, 5-carboxamidotryptamine (5-CT), was needed to inhibit acid secretion significantly. In contrast, neither the selective 5-HT1A agonist (+-)-8-hydroxy-2-(n-dipropylamino)-tetralin nor 5-HT2 agonist (+-)-1-(4-iodo-2,5-dimethoxyphenyl)-2-aminopropane (0.88 or 2.6 mumol/kg) attenuated gastric acid secretion. Thus, the data suggest that the site mediating inhibition of acid secretion by exogenous 5-HT belongs to the 5-HT1 family, but may not be of the 5-HT1A subtype.

Menogaril, a semisynthetic anthracycline antibiotic, was administered to patients with metastatic adenocarcinoma of the prostate. Forty-five patients with measurable disease and 45 patients with evaluable disease received 150-200 mg/m2 over 1 hour every 28 days. There were three partial responses (PR) among 87 patients evaluable for response. Myelosuppression was dose limiting. There were two deaths related to leukepenia. Other toxicities included phlebitis, alopecia, nausea and vomiting. One patient developed acute nonlymphocytic leukemia. Menogaril at these doses and schedule is toxic and has no significant antitumor activity in metastatic adenocarcinoma of the prostate.

Prostate cancer is the second leading cause of cancer death in men. Recently, there has been increased interest in the use of prostate-specific antigen (PSA) as a screening test for prostate cancer. The PSA test offers the benefit of a reproducible, objective value that is independent of the examiner's skill; however, it does not seem to be effective alone as a screening test for prostate cancer. Additionally, the efficacy of treatment for prostate cancer with radiation therapy or radical prostatectomy remains to be demonstrated. Thus, further studies demonstrating an improved mortality in prostate cancer with PSA screening need to be performed before universal screening with PSA can be recommended. Meanwhile, education of the patient regarding the risks, benefits, and costs of PSA screening and subsequent treatment should be addressed before performing a PSA test.

In a Southwest Oncology Group phase II clinical trial, 68 patients with hormone refractory carcinoma of the prostate were treated with a combination of doxorubicin, mitomycin C and 5-fluorouracil. Of the patients 11 were classified as good risk and 57 as poor risk. There were 1 complete and 10 partial remissions for a response rate of 16.2% (exact 95% confidence interval 8.4 to 27.1%). Median survival was 9 months (maximum 14) for good risk patients and 10 months (maximum 42) for poor risk patients. Toxicity was significant with leukopenia identified as dose limiting. Because of the low rate of response and significant toxicity, this regimen cannot be recommended as standard therapy for metastatic hormone refractory prostate cancer.

Intracisternal (ic) injection of the neutral endopeptidase-24.11 inhibitor phosphoramidon (1-100 nmol) produced a dose-dependent inhibition of gastric acid secretion in 2-h pylorus-ligated rats. The response resulted from a reduction in acid concentration and volume. Likewise, ic injection of another neutral endopeptidase-24.11 inhibitor Zincov (200 nmol) produced a 63% inhibition in gastric acid output. In contrast, neither intravenous injection of phosphoramidon (100 nmol) nor ic injection of the aminopeptidase inhibitor amastatin (100 nmol) produced any change in gastric acid secretion. The inhibitory effect of ic phosphoramidon (10 nmol) was not reversed by a dose of naloxone sufficient to antagonize the acid inhibitory effects of ic [D-Ala2-D-met5]enkephalinamide (8.5 nmol). Moreover, phosphoramidon-induced inhibition of acid was not reduced by the centrally effective bombesin antagonist N-acetyl-GRP(20-26)-O-CH3 or by reserpine pretreatment at a dose effective to antagonize ic neurotensin-induced inhibition in acid secretion. These results suggest that an endogenous neutral endopeptidase-24.11 sensitive substrate may act in the brain to inhibit gastric acid output by mechanisms independent of CNS opiate, bombesin or neurotensin activity.

Incidental prostate cancer is an indolent disease typically characterized by a benign clinical course. This is not clearly established, however, as recent reports suggest that up to 27% of cases progress with long-term follow-up. The indolent history of this disease led initially to the hypothesis that mutations of the p53 gene would be an infrequent event in this patient population. Archival specimens from 24 patients with Stage A1 carcinomas were evaluated for abnormal p53 expression. In 23 patients the disease was diagnosed after transurethral resection for bladder outlet obstructive symptoms, and in one patient after a radical prostatectomy. Using a monoclonal antibody (PAb 240) and an immunohistochemical technique, a total of 36 microfoci of tumor were evaluated. Thirteen (36%) microfoci were positive with an intense nuclear staining pattern (2+), and eight (22%) microfoci had an intermediate staining pattern. Four areas of prostatic intraepithelial neoplasia also stained positively with a 2+ staining pattern. These results suggest that abnormal p53 expression is a feature of a significant number of incidental prostatic carcinomas and that this occurrence is an early event in the development of the malignant phenotype.

The expression of the mutant p53 tumor suppressor gene was evaluated in 33 human prostate carcinomas. Using an immunohistochemical method with monoclonal antibodies PAb 1801 and PAb 240, 26 (79%) tumors demonstrated positive immunostaining for mutant p53. Only areas of glandular tumor were positive, with adjacent stromal elements and areas of glandular hyperplasia being negative. The predominant staining pattern was cytoplasmic. This pattern may be related to p53 binding to certain heat shock proteins (HSP 72/73), as a monoclonal antibody to these proteins demonstrated a cytoplasmic location as well. These results demonstrate that abnormal p53 expression is a frequent event in prostate cancer.

The Southwest Oncology Group (SWOG) performed a phase II trial of a combination of ifosfamide/mesna/cisplatin in patients with metastatic soft-tissue sarcoma who had previously received one chemotherapeutic regimen. A total of 39 patients were registered in the study, including 7 treated during a limited-institution pilot phase; 38 patients were fully eligible and evaluable. During the pilot phase, patients were treated with 2.5 g/m2 ifosfamide daily on days 1-3, 2.5 g/m2 mesna daily on days 1-4, and 100 mg/m2 cisplatin on days 2 and 9. Due to excessive myelosuppression, the day-9 cisplatin dose was dropped when the study was opened groupwide, and the subsequent 32 patients were treated at 3- to 4-week intervals with 2.5 g/m2 ifosfamide daily on days 1-3, 2.5 g/m2 mesna daily on days 1-4, and 100 mg/m2 cisplatin on day 2. Myelosuppression was severe, with granulocytopenia (< 0.5 x 10(9)/l) being observed in 26 of 38 patients. Three cases of National Cancer Institute grade 3 or 4 nephrotoxicity (serum creatinine, > 3 times the normal value) and three cases of grade 3 or 4 central nervous system toxicity were reported. Overall, three complete and five partial responses were achieved, for a major response rate of 21%. The median survival of all patients was 11 months. We conclude that ifosfamide-based chemotherapy can produce objective responses in previously treated patients with metastatic soft-tissue sarcoma but that cisplatin increases the toxicity of therapy. Phase II trials of new agents are needed to identify drugs with clinical activity in the treatment of soft-tissue sarcomas.

Purpose: Previous reports of chemotherapy in patients with adrenal cancer have described responses to cisplatin (CDDP). Because of these reports of good results, a phase II trial that used CDDP with and without mitotane (o,p'DDD) was initiated., Patients and Methods: Patients with metastatic or residual adrenocortical carcinoma with objectively measurable disease or biochemical abnormalities were divided into good-risk and poor-risk categories. The latter received CDDP 100 mg/m2 intravenously, and the former received 75 mg/m2. o,p'DDD was administered at a 1,000-mg dose orally four times a day along with cortisone acetate and Florinef (fludrocortisone acetate; Bristol-Myers Squibb Co, Princeton, NJ)., Results: Of a total of 42 patients entered onto the study, 37 were eligible. Twenty-nine patients received good-risk and eight received poor-risk doses of CDDP. Functioning tumors were present in 45% of patients. Objective responses were noted in 30% (11 of 37) patients (95% confidence interval, 16% to 50%). Response duration was 7.9 months, and the median time to response was 76 days. The median survival of the 37 eligible patients was 11.8 months, and a significant survival advantage was found for patients who underwent prior surgical removal of their primary tumor or bulky disease, who had a performance status of 0 or 1, or who had synchronous metastatic disease. Toxicity of the CDDP and o,p'DDD combination was moderate to severe, and the most common side effects were gastrointestinal, renal, and neurologic., Conclusion: The regimen of CDDP and o,p'DDD has activity in patients with adrenocortical carcinoma; however, the toxicity of this treatment was moderate to severe.

Atropine autoinjectors are issued to aviators for use in the event of organophosphate poisoning on the battlefield. This investigation assessed the effects of unchallenged 2 mg and 4 mg doses on flight performance, vision, tracking, cognitive performance, and electroencephalograms of 12 Army aviators. Effects were seen most often with the 4 mg dose in terms of aircraft control problems, vision disturbances, impaired tracking, reduced cortical activation, and decreased cognitive skill. These problems indicate helicopter tactical flight is dangerous after an unchallenged 4 mg dose. Other types of flight should also be avoided for at least 12 h after atropine.

The effects of serotonin (5HT) and a thyrotropin-releasing hormone (TRH) analogue, RX77368, on vagal control of gastric acid secretion were studied. Microinjection of RX77368 (0.66 pmol in 10 nl), but not 5HT (8 pmol in 10 nl), into the dorsal vagal complex (DVC) evoked a significant increase in acid output. When the same doses of RX77368 and 5HT were co-injected, the amount of acid secreted was significantly greater than that due to RX77368 alone. Thus, 5HT and the TRH analogue interact within the DVC to enhance vagal stimulation of acid secretion. The study suggests a possible functional significance of raphe TRH/serotonergic tracts projecting to the DVC.

This study examined the effectiveness of audiotaped imagery in reducing anxiety and improving test performance among first-year nursing students. Volunteer subjects were randomly assigned to three groups, imagery-only, imagery/relaxation, and a no-treatment control group. Pottest state anxiety scores in these groups were significantly lower (p = .001) than in the no-treatment control group. Test performance did not differ significantly (p = .067). Subjects using the audiotaped imagery reported an increased sense of well-being, improved ability to sleep, greater energy, and improved self-confidence.

For many years, it has been recognized that a portion of female breast cancer is inherited. More recently, the probable contribution of heredity to at least a subset of male breast cancer also has surfaced. This report, which describes affected brothers, a half sister, and the common paternal grandmother, provides further support for the role of genetic factors in male breast cancer. Also noteworthy was the presence of prostate carcinoma in the sibling with bilateral disease and in the unaffected father.

Beginning in 1981, 28 patients with advanced seminoma were treated with combination chemotherapy followed by irradiation to evaluate the possibility of improved survival using both modalities. The treatment protocol consisted of two courses of vincristine, actinomycin-D, and cyclophosphamide followed by reassessment. Those initially presenting with Stage B3 disease who achieved a complete response to two cycles of chemotherapy then underwent irradiation. All others were given a third course of chemotherapy before undergoing irradiation. The pre-radiation portion of this protocol produced a complete response rate of only 25 percent, substantially less than other, more recent, protocols. Radiation therapy produced a complete response in 69 percent of those who did not achieve a complete response from chemotherapy, increasing the complete response rate from 25 percent to 64 percent. Given this response rate to radiation therapy and the difficulty of dissection and associated morbidity with the surgical excision of postchemotherapy residual masses, the best option at this time may be observation with salvage chemotherapy and/or radiation reserved for those with disease progression.

The Patient Self-Determination Act now requires hospitals, nursing homes, and health maintenance organizations to ask patients if they have executed and are in possession of a living will. This article provides a brief historical perspective of what living wills are, how patient autonomy has contributed to their existence, and what distinguishes a living will from a durable power of attorney for health care. Included are working examples of these advance directives and a description of the University of Kansas Cancer Unit's positive experience with living wills. The final section discusses the meaning of certain pivotal terms, looks at the current under-utilization of living wills, and closes with an examination of the Blackhall thesis of futility.