Mechanotransduction-induced interplay between phospholamban and yes-activated protein induces smooth muscle cell hypertrophy

The gastrointestinal system is a hollow organ affected by fibrostenotic diseases that cause volumetric compromise of the lumen via smooth muscle hypertrophy and fibrosis. Many of the driving mechanisms remain unclear. Yes-associated protein-1 (YAP) is a critical mechanosensory transcriptional regulator that mediates cell hypertrophy in response to elevated extracellular rigidity. In the type 2 inflammatory disorder, eosinophilic esophagitis (EoE), phospholamban (PLN) can induce smooth muscle cell hypertrophy. We used EoE as a disease model for understanding a mechanistic pathway in which PLN and YAP interact in response to rigid extracellular substrate to induce smooth muscle cell hypertrophy. PLN-induced YAP nuclear sequestration in a feed-forward loop caused increased cell size in response to a rigid substrate. This mechanism of rigidity sensing may have previously unappreciated clinical implications for PLN-expressing hollow systems such as the esophagus and heart.

Plasminogen Activator Inhibitor-1 as a Marker of Esophageal Functional Changes in Pediatric Eosinophilic Esophagitis

BACKGROUND & AIMS

Esophageal remodeling in eosinophilic esophagitis (EoE) can lead to esophageal rigidity with eventual luminal compromise and stenoses. Gauging esophageal functional alterations in EoE is challenging. An epithelial marker of functional remodeling would impact EoE management.

METHODS

Esophageal biopsy specimens from children with and without EoE and primary human esophageal epithelial cells were used for PAI-1 immunohistochemistry, and cell proliferation experiments. PAI-1 immunostaining and basal cell hyperplasia were assessed in the context of concurrently obtained esophageal compliance measures on endoscopic functional lumen imaging probe (EndoFLIP).

RESULTS

EndoFLIPs were performed in 45 children (32 with and 13 without EoE). Epithelial PAI-1 was increased in patients with active EoE versus inactive or control patients (P < .01). Esophageal compliance was lower in EoE patients versus controls, particularly in the proximal esophagus (P < .001). Proximal compliance was the strongest predictor of EoE (AUROC 0.88, 95% CI 0.77, 0.98) with esophageal compliance of less than 2.6%mL/mmHg demonstrating 82% sensitivity and 84% specificity for EoE. PAI-1 inhibition significantly diminished esophageal epithelial cell proliferation, suggesting PAI-1 could trigger basal cell hyperplasia. A composite mid-esophageal BZH + PAI-1 score was the strongest predictor of altered compliance (P = .02, AUROC 0.89 (95% CI 0.80, 0.99).

CONCLUSIONS

PAI-1 is significantly elevated in pediatric EoE and distinguishes altered compliance in children. PAI-1 may be a novel disease marker and therapeutic target.

TGFβ1 single-nucleotide polymorphism C-509T alters mucosal cell function in pediatric eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic Th2 antigen-driven disorder associated with tissue remodeling. Inflammation and remodeling lead to esophageal rigidity, strictures, and dysphagia. TGFβ1 drives esophageal remodeling including epithelial barrier dysfunction and subepithelial fibrosis. A functional SNP in the TGFβ1 gene that increases its transcription (C-509T) is associated with elevated numbers of esophageal TGFβ1-expressing cells. We utilized esophageal biopsies and fibroblasts from TT-genotype EoE children to understand if TGFβ1 influenced fibroblast and epithelial cell function in vivo. Genotype TT EoE esophageal fibroblasts had higher baseline TGFβ1, collagen1α1, periostin, and MMP2 (p < 0.05) gene expression and distinct contractile properties compared with CC genotype (n = 6 subjects per genotype). In vitro TGFβ1 exposure caused greater induction of target gene expression in genotype CC fibroblasts (p < 0.05). Esophageal biopsies from TT-genotype subjects had significantly less epithelial membrane-bound E-cadherin (p < 0.01) and wider cluster distribution at nanometer resolution. TGFβ1 treatment of stratified primary human esophageal epithelial cells and spheroids disrupted transepithelial resistance (p < 0.001) and E-cadherin localization (p < 0.0001). A TGFβ1-receptor-I inhibitor improved TGFβ1-mediated E-cadherin mislocalization. These data suggest that EoE severity can depend on genotypic differences that increase in vivo exposure to TGFβ1. TGFβ1 inhibition may be a useful therapy in subsets of EoE patients.

Development and Application of a Functional Human Esophageal Mucosa Explant Platform to Eosinophilic Esophagitis

There is an increasing prevalence of esophageal diseases but intact human tissue platforms to study esophageal function, disease mechanisms, and the interactions between cell types in situ are lacking. To address this, we utilized full thickness human donor esophagi to create and validate the ex vivo function of mucosa and smooth muscle (n = 25). Explanted tissue was tested for contractile responses to carbachol and histamine. We then treated ex vivo human esophageal mucosa with a cytokine cocktail to closely mimic the Th2 and inflammatory milieu of eosinophilic esophagitis (EoE) and assessed alterations in smooth muscle and extracellular matrix function and stiffening. We found that full thickness human esophagus as well as the individual layers of circular and longitudinal muscularis propria developed tension in response to carbachol ex vivo and that mucosa demonstrated squamous cell differentiation. Treatment of mucosa with Th2 and fibrotic cytokines recapitulated the majority of the clinical Eosinophilic Esophagitis Diagnostic Profile (EDP) on fluidic transcriptional microarray. Transforming growth factor-beta-1 (TGFβ1) increased gene expression of fibronectin, smooth muscle actin, and phospholamban (p < 0.001). The EoE cocktail also increased stiffness and decreased mucosal compliance, akin to the functional alterations in EoE (p = 0.001). This work establishes a new, transcriptionally intact and physiologically functional human platform to model esophageal tissue responses in EoE.

TGF-β1-induced PAI-1 contributes to a profibrotic network in patients with eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is an allergic disease of increasing worldwide incidence. Complications are due to tissue remodeling and involve TGF-β1-mediated fibrosis. Plasminogen activator inhibitor 1 (PAI-1/serpinE1) can be induced by TGF-β1, but its role in EoE is not known.

OBJECTIVE

We sought to understand the expression and role of PAI-1 in patients with EoE.

METHODS

We used esophageal biopsy specimens and plasma samples from control subjects and patients with EoE, primary human esophageal epithelial cells, and fibroblasts from patients with EoE in immunohistochemistry, quantitative PCR, and immunoassay experiments to understand the induction of PAI-1 by TGF-β1, the relationship between PAI-1 and esophageal fibrosis, and the role of PAI-1 in fibrotic gene expression.

RESULTS

PAI-1 expression was significantly increased in epithelial cells of biopsy specimens from patients with active EoE compared with that seen in biopsy specimens from patients with inactive EoE or control subjects (P < .001). Treatment of primary esophageal epithelial cells with recombinant TGF-β1 increased PAI-1 transcription, intracellular protein expression, and secretion. Esophageal PAI-1 expression correlated with basal zone hyperplasia, fibrosis, and markers of esophageal remodeling, including vimentin, TGF-β1, collagen I, fibronectin, and matrix metalloproteases, and plasma PAI-1 levels correlated with plasma TGF-β1 levels. PAI-1 inhibition significantly decreased baseline and TGF-β1-induced fibrotic gene expression.

CONCLUSIONS

PAI-1 expression is significantly increased in the epithelium in patients with EoE and reflects fibrosis, and its inhibition decreases TGF-β1-induced gene expression. Epithelial PAI-1 might serve as a marker of EoE severity and form part of a TGF-β1-induced profibrotic network.

The TGFβ1 Promoter SNP C-509T and Food Sensitization Promote Esophageal Remodeling in Pediatric Eosinophilic Esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic antigen mediated disease associated with substantial esophageal remodeling and fibrosis. The functional TGFβ1 promoter SNP C-509 associates with renal fibrosis and asthma. The effect of TGFβ1 genotype and EoE severity or potential gene-environment interactions have not been previously reported in EoE.

METHODS

Genotype at TGFβ1 C-509T and remodeling was analyzed in 144 subjects with EoE. The severity of remodeling and inflammation was analyzed in the context of IgE sensitization to food antigens and C-509T genotype.

RESULTS

The TGFβ1 promoter C-509 genotypes CC, CT, and TT were 35%, 52%, and 13%, respectively. Sixty-six percent of subjects were sensitized to foods by positive skin prick test (SPT) or serum specific IgE. TT genotype subjects had significantly more TGFβ1 (CC subjects = 1300 per mm2; TT = 2250 per mm2) (p<0.05) and tryptase (CC subjects = 145 per mm2: TT = 307 per mm2) (p<0.05) positive cells and higher epithelial remodeling scores (2.4 vs 3.7, p<0.001) than CC subjects. The differences in TGFβ1 and tryptase positive cells as well as fibrosis were significantly increased when there was concurrent food sensitization. Food sensitization alone did not associate with any parameters of inflammation or remodeling.

CONCLUSIONS

Our data support a gene-environment interaction between food and genotype at C-509 that modulates disease severity in EoE. Since EoE subjects often continue to consume foods to which they are sensitized, these findings may have clinical relevance for disease management.

Extracellular vesicles from a muscle cell line (C2C12) enhance cell survival and neurite outgrowth of a motor neuron cell line (NSC-34)

Introduction

There is renewed interest in extracellular vesicles over the past decade or 2 after initially being thought of as simple cellular garbage cans to rid cells of unwanted components. Although there has been intense research into the role of extracellular vesicles in the fields of tumour and stem cell biology, the possible role of extracellular vesicles in nerve regeneration is just in its infancy.

Background

When a peripheral nerve is damaged, the communication between spinal cord motor neurons and their target muscles is disrupted and the result can be the loss of coordinated muscle movement. Despite state-of-the-art surgical procedures only approximately 10% of adults will recover full function after peripheral nerve repair. To improve upon such results will require a better understanding of the basic mechanisms that influence axon outgrowth and the interplay between the parent motor neuron and the distal end organ of muscle. It has previously been shown that extracellular vesicles are immunologically tolerated, display targeting ligands on their surface, and can be delivered in vivo to selected cell populations. All of these characteristics suggest that extracellular vesicles could play a significant role in nerve regeneration.

Methods

We have carried out studies using 2 very well characterized cell lines, the C2C12 muscle cell line and the motor neuron cell line NSC-34 to ask the question: Do extracellular vesicles from muscle influence cell survival and/or neurite outgrowth of motor neurons?

Conclusion

Our results show striking effects of extracellular vesicles derived from the muscle cell line on the motor neuron cell line in terms of neurite outgrowth and survival.

Providing a community-based cancer risk assessment service for a socially and ethnically diverse population

BACKGROUND

Patients from ethnic minorities are under-represented in referrals to cancer genetics services. In a regional genetics centre that serves two London boroughs, the existing service attracts 3% of its referrals from Black and Minority Ethnic (BME) and other ethnic groups, despite the fact that these groups make up 34% of the population.

OBJECTIVES

To improve access to familial cancer risk assessment in a socially and ethnically diverse population.

SETTING

The London boroughs of Lambeth and Southwark.

DESIGN

Community-based, nurse-led clinics were established for people who were concerned about their familial cancer risk. Patients were asked to triage themselves by answering three questions. Self-referral was encouraged.

MAIN OUTCOME MEASURES

Data were gathered on ethnicity of clients, cancer risk, source of referral and patient and health professional satisfaction with the service.

RESULTS

Of the 415 people who have accessed the service, 46% were from not White British groups and 67% referred themselves to the service, demonstrating the success of this model in reaching 'hard to reach' groups. Thirty-seven percent of patients were assessed as being at population risk and 63% were assessed as being at moderate risk or higher, showing that the clinics were meeting an unmet need in the community.

Benefit determination under managed care for substance abuse treatment clients

The purposes of this study were to examine the process of benefit determination, approval, and variation among Substance Abuse Treatment (SAT) clients. A convenience sample of 20 SAT clients admitted to 1 of 2 treatment programs within Matrix Center were followed. Clients of clinicians who agreed to participate were given an invitation letter to hear more about the study. After informed consent, clients granted 3 interviews and gave permission for the researcher to examine client records to ascertain the benefit determination process. Referral sources were the clients' insurances, their MDs, a counselor, hospital, Employee Assistance Program, case manager, and another treatment program. Ten of the insurances were PPOs, 9 were HMOs, and 1 was a contract. All but 2 had benefits managed by a behavioral care organization (MBCO). Case managers of the MBCOs were all clinicians, most frequently ACSWs. All programs authorized outpatient care and the first approval authorized from 6 to 52 visits. From 1 to 5 different authorizations were used for each client. The co-pay ranged from $0 to $35 per visit. This study illustrates the details of how benefits for substance abuse treatment under managed care are negotiated and used.

Gamma-hydroxybutyric acid: patterns of use, effects and withdrawal

Gamma-hydroxybutyric acid (GHB) is gaining popularity as a drug of abuse. Reports of toxicity and lethality associated with GHB use have increased. This survey study was designed to identify patterns of GHB use, its effects, and withdrawal syndrome. A survey inquiring about the effects of GHB was administered to 42 users. The results showed that GHB was used to increased feelings of euphoria, relaxation, and sexuality. Adverse effects occurred more frequently in daily users and polydrug users than in occasional GHB users. Loss of consciousness was reported by 66%, overdose by 28%, and amnesia by 13% of participants during GHB use and by 45% after GHB use. Three daily users developed a withdrawal syndrome that presented with anxiety, agitation, tremor, and delirium. Participants described GHB intoxication as having similarities to sedative-hypnotic or alcohol intoxication. Regular use has been shown to produce tolerance and dependence. Participants dependent on GHB reported using multiple daily doses around the clock. High frequency users appeared at the greatest risk for developing withdrawal delirium and psychosis after abrupt discontinuation of GHB use.

Seasonal changes in serum leptin, food intake, and body weight in photoentrained woodchucks

Male woodchucks (Marmota monax) were maintained in northern vs. southern hemisphere photoperiods, provided feed and water ad libitum, and evaluated every 2 wk for 23 mo for body weight, absolute and relative food intake, body temperature, serum testosterone, and serum concentrations of leptin measured using an anti-mouse leptin enzyme-linked immunoassay. During late spring and summer, body weight increased 56 +/- 4% above winter nadirs, and during the autumn and early winter weights decreased 27 to 43% below midsummer maxima. Serum leptin initially increased during increases in body weight, in the late spring, reached peak values (490 +/- 32 pg/ml) in summer during the initial decline in body weight, and later decreased along with body weight to reach basal values (20 +/- 5 pg/ml) in late winter. Spontaneous declines in food intakes in summer began 2-6 wk before resulting declines in body weight and occurred during increases in leptin >100 pg/ml. The rate of decline in food intakes was greatest when serum leptin was at or near peak values. Food intake increased in late winter when leptin was low and 7-10 wk before resulting increases in body weight. Testis recrudescence occurred when leptin was declining to near basal levels. The results suggest that leptin is involved in the hormonal regulation of the circannual cycle in the drive for voluntary food intake in this species.

Substance abuse policy and peace in the Middle East: a Palestinian and Israeli partnership

This paper describes the working exchange between Israelis, Palestinians and international experts who engaged in a process to promote communications, cooperation and coordination of efforts directed toward peace as well as the prevention and treatment of drug abuse in the region. From 1997 to 1999, a program of training workshops and courses, drug prevention and treatment skills development and collaborative research was conducted on the basis of mutual respect and cooperation among Palestinians and Israelis. By tapping into the issue of substance abuse and by focusing on its professional and academic dimensions, this initiative engaged representative delegations of the police force, academia, treatment centers and various government ministries. While events of this period underscored the dependence of "bottom-up" peace initiatives on the prevailing political situation, the experience revealed the vital role of NGO frameworks in providing a safety net for promoting and sustaining relations as well as addressing an issue of common concern. This case study shows that addiction professionals, both clinicians and researchers, can be instrumental in conflict resolution as well as the prevention and treatment of drug abuse.

Cognitive impairment in individuals currently using methamphetamine

Although there are increasing reports of methamphetamine use, studies examining the cognitive consequences of methamphetamine have not been performed on a population currently using the drug. To characterize this population, 65 people currently using MA regularly and 65 non-users were given a battery of cognitive tests. The battery included recall, recognition, Digit Symbol, Trail Making A & B, Stroop, Wisconsin Card Sort, backward digit span, and the FAS test of verbal fluency. The methamphetamine users were significantly more impaired on recall tasks, digit symbol, Stroop color words, and Trail Making B, but scores fell within the normal ranges on the other measures.

The matrix model of outpatient stimulant abuse treatment: history and description

The Matrix model was originally developed in response to the cocaine epidemic of the 1980s. The program consists of relapse prevention groups, education groups, social support groups, individual counseling, and urine and breath testing delivered in a structured manner over a 16-week period. The treatment is a directive, nonconfrontational approach which focuses on current issues and behavior change. Several evaluations of the model have supported its usefulness and efficacy with methamphetamine (MA) users. Methamphetamine users appear to respond to treatment similarly to cocaine users and many continue to show improvements at follow-up.

The CSAT methamphetamine treatment program: research design accommodations for "real world" application

The Methamphetamine Treatment Program (MTP), funded by the Center for Substance Abuse Treatment, has the objectives of implementing the Matrix outpatient model and evaluating that model in comparison to the existing community "treatments as usual." Seven organizations in three western states (California, Montana, and Hawaii) were selected to participate in this randomized, controlled, multisite project in what constitutes the largest trial to date of treatment for methamphetamine (MA) dependence. One hundred fifty MA-dependent patients recruited at each site are randomly assigned to receive either the Matrix model, a manualized program of intensive outpatient treatment, or the site's standard treatment, "treatment as usual." Participants are evaluated at admission, weekly during treatment, at the time of scheduled discharge, and at six and 12 months after admission. Dependent measures assess changes in drug use, HIV risk behaviors, quality of life, and patient satisfaction. Cost analyses to quantify treatment costs and determine the association between costs and clinical outcomes will be conducted. A number of adjustments in the original study design have been necessitated by the realities of community sites' strengths and limitations. Experiences from this multisite project will also provide a model for other efforts to transfer research-based treatments into community settings. This article describes the main aims of the project, the background and rationale for the study design, a brief description of the research plan, and methods implemented to protect the integrity of the science.

Methamphetamine and cocaine users: differences in characteristics and treatment retention

The use of methamphetamine and cocaine have both produced significant public health problems during the past two decades. Although these powerful psychostimulants have many common acute and chronic effects, there are some important differences in who uses these drugs and the consequences of their use. This article reports on two large cohorts of treatment-seeking cocaine and methamphetamine users who entered treatment at the same facility over the same four-year period of time. Patterns of use differed significantly. Cocaine users have more episodic use patterns, spend more money on purchasing their drugs, and use alcohol more heavily. Methamphetamine users include a higher proportion of women, more frequently use on a daily basis, use marijuana more often, and experience more severe medical and psychiatric consequences. Despite the differences in the stimulant drug effects and consequences, the treatment response to a multicomponent, outpatient program is very similar.

Integrating treatments for methamphetamine abuse: a psychosocial perspective

The recent West Coast experience with increased methamphetamine use is showing signs of spreading to other parts of the US. The risk of corresponding medical and psychosocial problems has led to a call to action at the highest levels of government. The next few years will likely witness a substantial increase in treatment research on methamphetamine abuse/dependence, with particular emphasis on the development and application of novel pharmacotherapies. The evaluation of these agents presupposes that we understand the clinical syndrome resulting from chronic methamphetamine use. To establish a clear picture of the biological and psychological sequellae of methamphetamine use, we compare two cohorts (500 methamphetamine and 224 cocaine users) treated at the same outpatient clinic over the past nine years, using identical manualized treatments. The results suggest that while there are important differences in group characteristics and drug effects, the total response to treatment was quite comparable.

Providing high-quality care for children

Because home care traditionally has served older patients under Medicare, some providers tend to treat in-home pediatric patients like "little adults." To offer children and their families the specialty care that they require and deserve, one agency limits its services exclusively to pediatrics.

Ritanserin in the treatment of alcohol dependence--a multi-center clinical trial. Ritanserin Study Group

Four hundred and twenty-three alcohol dependent subjects were enrolled into a 12-week randomized, double-blind, placebo-controlled study to determine the safety and efficacy of the 5-HT2 receptor antagonist, ritanserin (2.5 mg/day or 5 mg/day), in reducing alcohol intake and craving. All subjects received 1 week of single-blind placebo prior to randomization into the 11-week double-blind phase. Additionally, all subjects received weekly individual sessions of manual-guided cognitive-behavioral therapy. Comparing the single-blind period with endpoint, there was approximately a 23% reduction in drinks/day; 34% fall in the total number of drinking days/week; 22% decrease in drinks/drinking day; and a 37% diminution in alcohol craving for all treatment groups. All treatment groups experienced a beneficial clinical outcome as assessed by the Clinical Global Impression Scale. There was, however, no significant difference between treatment groups on any of these measures of alcohol drinking, craving, or clinical outcome. Subjects were of relatively high social functioning at baseline, and this did not change significantly during treatment. Treatment groups did not differ significantly on either medication compliance or reported adverse events. Ritanserin treatment was associated with a dose-related prolongation of subjects' QTc interval recording on the electrocardiogram. These results suggest that alcohol dependent subjects can show marked clinical improvement within a structured alcohol treatment program. These findings do not support an important role for ritanserin in the treatment of alcohol dependence.

What happens when a demonstration project ends. Consequences for a clinic and its clients

The Los Angeles Enhanced Methadone Maintenance Project was a 5-year research demonstration project funded by the National Institute on Drug Abuse with the goal of reducing high-risk behavior for human immunodeficiency virus (HIV) among heroin users. A clinic was established for the purposes of the study and 500 clients with high-risk profiles were recruited into treatment. Follow-up assessments demonstrated that clients had reduced their drug use, criminal behavior, and HIV-risk behaviors after entering treatment. At the end of the project clients were given the option of continuing treatment at the clinic on a fee-for-service basis, transferring to another treatment provider, or undergoing detoxification. Clients who were eligible for Medicaid were likely to continue receiving methadone treatment, but those without Medicaid funding were not. The implications of terminating treatment among a high-risk population recruited into a research demonstration project are discussed.

Reasons for discharge from methadone maintenance for addicts at high risk of HIV infection or transmission

This article reports on a methadone maintenance program that had the goal of retaining in treatment heroin addicts at high risk of HIV infection and/or transmission. Subjects were recruited from four-high-risk target groups and randomly assigned to either an enhanced or standard methadone maintenance group. The analysis examined predictors of any type of discharge, negative discharge, and circumstantial discharge. Discharge for any reason was more likely for younger individuals, sex industry workers, and high-risk sex partners. Legal supervision at intake and coercion into treatment reduced the probability of discharge for any reason. HIV-positive individuals were more likely to discharge for circumstantial reasons than negative reasons. The probability of circumstantial discharge was increased for males, individuals reporting suicidal ideation, and those scoring higher on an impulse expression scale. The likelihood of circumstantial discharge was decreased for individuals who reported more sources of legal income or who lived someone using illegal drugs. Participation in the enhanced treatment group appeared to reduce the probability of negative, compared with circumstantial, discharge. The findings should assist methadone treatment providers in targeting individuals at high probability of discharge for special efforts to increase treatment retention and to reengage them back into treatment after discharge, as part of a harm-reduction strategy to minimize risks of HIV infection and/or transmission.

Toward a molecular genetic analysis of spermatogenesis in Drosophila melanogaster: characterization of male-sterile mutants generated by single P element mutagenesis

We describe 83 recessive autosomal male-sterile mutations, generated by single P element mutagenesis in Drosophila melanogaster. Each mutation has been localized to a lettered subdivision of the polytene map. Reversion analyses, as well as complementation tests using available chromosomal deficiencies, indicate that the insertions are responsible for the mutant phenotypes. These mutations represent 63 complementation groups, 58 of which are required for spermatogenesis. Phenotypes of the spermatogenesis mutants were analyzed by light microscopy. Mutations in 12 loci affect germline proliferation, spermatocyte growth, or meiosis. Mutations in 46 other loci disrupt differentiation and maturation of spermatids into motile sperm. This collection of male-sterile mutants provides the basis for a molecular genetic analysis of spermatogenesis.

Role of the extracellular matrix in tissue-specific gene expression in the sea urchin embryo

The role of extracellular matrix (ECM) in the differentiation of tissue types was examined in embryos of Strongylocentrotus purpuratus. We have examined the expression of various tissue-specific molecular markers after disrupting the ECM by culturing embryos in the presence of beta-aminoproprionitrile fumarate (BAPN), which disrupts collagen deposition, and beta-D-xyloside, which disrupts proteoglycan metabolism. The markers examined included accumulation of primary mesenchyme-specific mRNA (SM 50); an aboral ectoderm-specific mRNA (Spec 1); and a gut-specific enzyme, alkaline phosphatase. Treatment with BAPN or beta-D-xyloside results in developmental arrest at the mesenchyme blastula stage. Although spicule formation is inhibited, the accumulation of SM 50 transcripts and the synthesis of most of the prominent spicule matrix proteins is similar to that of control embryos. Spec 1 mRNA, in contrast, while accumulating to a significant extent when collagen and proteoglycan metabolism is disrupted, does accumulate to a level somewhat lower than that seen in control embryos. Additionally, the postgastrula rise in gut-specific alkaline phosphatase is reversibly inhibited by BAPN and xyloside treatment. These results demonstrate a differential effect of the ECM on expression of tissue-specific molecular markers.

Comparison of two naltrexone treatment programs: naltrexone alone versus naltrexone plus behavior therapy

During a period of one year naltrexone was given to twenty-nine subjects. Fifteen of these subjects concurrently participated in a comprehensive behavior therapy program. The subjects in this naltrexone/behavior therapy group were maintanine on naltrexone for nearly twice as long as naltrexone group clients who received no therapy. If the chances for readdiction are reduced by increased time on naltrexone, then the data states the naltrexone should be dispensed as part of a broader therapeutic strategy. Follow-up data, which will be collected during the next year will test the validity of this hypothesis.

Red blood cell volume and distribution after bleed-out in the rat as determined by Cr51-labeled red blood cells

The distribution of red blood cells after bleed-out was determined in 20 Nembutalized rats (307.1–484.4 gm body weight), using Cr51-labeled red blood cells. The normal red blood cell volume was 2.20 ± 0.25 ml/100 gm body weight. On the average 68.5% of the red blood cells were removed by the bleed-out. Per total tissue the muscle contained most of the red blood cell volume remaining after bleed-out and together with the liver and bone about 65%. Per gram of tissue the spleen had the highest red blood cell volume after bleed-out. The volume of red blood cells remaining in the spleen and kidney was the same as found by Riecke and Everett in unbled Nembutalized rats.