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Primary myelofibrosis (PMF) is associated with morbidity and mortality. Ruxolitinib gained US FDA approval for treatment of intermediate/high-risk PMF in November 2011. We evaluated differences in survival and second primary malignancy (SPM) incidence among US PMF patients in the years before and after ruxolitinib approval.We conducted a retrospective study utilizing the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER)-18 database for PMF patients. We divided patients into five-year cohorts pre- (2007-2011) and post-ruxolitinib (2012-2016) approval and compared relative survival rates (RSRs) to the standard population and standardized incidence rates (SIRs) of SPMs between cohorts.We included 2020 patients diagnosed with PMF from 2007-2016 in this study. There was no difference in the four-year RSRs between cohorts (54 % vs. 57 %, p = 0.776). More patients developed SPMs in the post-ruxolitinib cohort (8% vs. 6%, p = 0.041). The majority of SPMs were hematologic with higher incidence of AML transformation in the post-ruxolitinib cohort (SIR 125.29 vs. 70.55).PMF prognosis remains poor in the years following ruxolitinib's approval. SPM incidence including AML transformation is higher in the years after approval. Further studies are needed to determine the true impact of ruxolitnib on population outcomes.

Myelodysplastic syndromes (MDS), a spectrum of heterogeneous hematopoietic stem cell diseases, vary in clinical severity, response to therapy, and propensity toward progression to acute myeloid leukemia. These are acquired clonal disorders resulting from somatic mutations within the hematopoietic stem or progenitor cell population. Understanding the natural history and the risk of developing leukemia and other adverse outcomes is dependent on access to well-annotated biospecimens linked to robust clinical and molecular data. To facilitate the acquisition and distribution of MDS biospecimens to the wider scientific community and support scientific discovery in this disease, the National MDS Natural History study was initiated by the National Heart, Lung, and Blood Institute (NHLBI) and is being conducted in collaboration with community hospitals and academic medical centers supported by the National Cancer Institute (NCI). The study will recruit up to 2000 MDS patients or overlapping myeloproliferative neoplasms (MDS/MPN) and up to 500 cases of idiopathic cytopenia of undetermined significance (ICUS). The National MDS Natural History Study (NCT02775383) will offer the world's largest disease-focused tissue biobank linked to longitudinal clinical and molecular data in MDS. Here, we report on the study design features and describe the vanguard phase of 200 cases. The study assembles a comprehensive clinical database, quality of life results, laboratory data, histopathology slides and images, genetic information, hematopoietic and germline tissues representing high-quality biospecimens and data from diverse centers across the United States. These resources will be available to the scientific community for investigator-initiated research.

The objective of this study is to evaluate the impact of certified child life specialists (CCLSs) on the emotional responses of children undergoing laceration repair in the emergency department (ED).Patients 4 to 12 years of age who required laceration repair by suturing were prospectively enrolled at an urban tertiary pediatric ED. Certified child life specialists are not available at all times in our institution, allowing for a priori categorization of subjects into 2 comparison groups, those with and those without CCLS involvement. Subjects requiring anxiolysis, pharmacologic sedation, narcotics, or physical restraint were excluded. The Children's Emotional Manifestation Scale, a previously validated Likert-like tool, was used to quantify the patients' distress, with a higher score reflecting a more emotional child. Just before placement of the first suture, subjects were scored by trained independent observers. Baseline data included age, sex, race, type of local anesthetic, length and location of laceration, and analgesics administered. The primary endpoint of emotional score was compared with a 2-tailed Mann-Whitney U test, with a P0.05 considered statistically significant.Two hundred one patients constituted the final study cohort, with 103 (51%) having CCLS involvement. Study groups did not differ in regards to any baseline demographic or clinical characteristics. The median emotional score for patients with child life services was 7 (interquartile range, 6-9) versus 9 (interquartile range, 7.5-12) for those without (P0.0005).Certified child life specialist involvement is associated with less emotional distress for children undergoing laceration repair in the ED.

Arthroscopic techniques for the hip joint have evolved into endoscopic methods for extra-articular disorders. These endoscopic strategies provide a less invasive alternative to open procedures for traditionally recognized forms of pathology. Endoscopy has defined new disorders amenable to surgical correction and has redefined some of these existing disorders. The peritrochanteric and deep gluteal regions represent 2 of the most currently active areas of exploration. Peritrochanteric problems include trochanteric bursitis, full-thickness and partial-thickness tears of the abductors including the gluteus medius and minimus, and external coxa saltans (snapping iliotibial band). Deep gluteal disorders include piriformis syndrome, and other variations of deep gluteal syndrome, and ischiofemoral impingement. Each of these evolving areas is highlighted in this chapter.

Persons with behavioral disorders incur higher healthcare costs. Although they utilize behavioral health (BH) services others do not, they also have higher utilization of medical services: To determine the degree to which higher costs for persons with BH disorders are attributable to utilization of BH services, multiple chronic medical conditions (CMCs) or other issues specific to populations with BH disorders.Data base consisted of claims for 63,141 Medicaid beneficiaries, 49% of whom had one of 5 categories of BH disorder. Generalized linear models were used to identify relative impact of demographics, BH status, multiple CMCs and primary care access on total, behavioral, nonbehavioral, and medical/surgical costs.Number of CMCs was associated with significant increases in all cost categories, including behavioral costs. Presence of any BH disorder significantly influenced these same costs, including those not associated with BH care. Effect size in each cost category varied by BH group.BH status has a large impact on all healthcare costs, including costs of medical and other non-BH services. The number of CMCs affects BH costs independent of BH disorder. Results suggest that costs might be reduced through better integration of behavioral and medical health services.

Purpose To compare and investigate the rate of infection in patients with and without human immunodeficiency virus (HIV) who have implantable venous access devices placed by interventional radiologists. Materials and Methods Three hundred ninety-one patients undergoing radiologically guided placement of peripheral arm ports were grouped according to their HIV serologic status. Findings were prospectively reviewed in 393 peripherally placed arm ports that were implanted in the basilic, cephalic, or brachial vein under fluoroscopic or sonographic guidance over a 4-year span. Infectious complications were categorized according to severity (local or systemic) and time (periprocedural or late). Results Three hundred ninety-three ports have been indwelling for a total of 97,256 patient days (range, 1–694; mean duration, 247 days). Among the 30 catheter placements in 29 HIV-positive patients with a total exposure time of 7,242 days, five (one local and four systemic) infections occurred, resulting in a 16.6% overall infection rate, yielding 0.069 infections per 100 catheter days at risk (95% confidence interval [CI], 0.032–0.127). In the remaining 362 HIV-negative patients, 27 (14 local and 13 systemic) infectious complications (7.4%) occurred, translating into 0.030 infections per 100 catheter days (95% CI, 0.021–0.042). The odds ratio of getting an infection from the implantable arm ports in the HIV-positive group was 2.5 times higher than that of the HIV-negative group. The relative risk was similar and was calculated to be 2.3. The P value was .084 ( P Conclusions These results suggest a significant difference in the infectious complication rate encountered in HIV-positive patients compared with the general population. However, the HIV-positive peripheral arm port infection rate compares favorably with the surgically placed catheters and ports. Many more arm ports in HIV-positive patients must be evaluated for the data to achieve an acceptable level of statistical significance.

Aortic or brachiocephalic vessel injuries secondary to blunt thoracic trauma are relatively common and can occur throughout the length of the thoracic aorta or in various locations in the brachiocephalic vessels. Aortography remains the standard of reference for the diagnosis of these injuries despite recent technologic advances in other imaging modalities. The classic aortographic finding in aortic or brachiocephalic vessel injury consists of a large false aneurysm, typically protruding from the medial aspect of the aortic isthmus. However, intrathoracic aortic or brachiocephalic vessel injury can and does occur at any intrathoracic location and may exhibit a wide variety of radiographic appearances, thereby presenting a diagnostic challenge even for experienced trauma angiographers. Large false aneurysms may appear oval or rounded, tubular, or asymmetrically globular and may manifest in unusual locations such as the ascending aorta. Although smaller, irregularly shaped false aneurysms at atypical locations may be obscure or mimic ductus diverticula, their irregular, sharp margins allow them to be distinguished as injuries. The subtlety of aortic or brachiocephalic vessel injuries necessitates a high degree of suspicion along with meticulous imaging technique in all cases and the use of additional projections in equivocal cases for definitive diagnosis.

Introduction Many products labeled “herbal” or “all natural” (herbal/natural) that claim to enhance sexual performance and imply use for the treatment of erectile dysfunction (ED) are marketed as over-the-counter (OTC) dietary supplements. However, adulteration with undeclared phosphodiesterase type 5 (PDE5) inhibitors appears widespread. Aim To assess the availability, cost, origin, categorical content, and adulteration with PDE5 inhibitors of purported herbal/natural OTC dietary supplements claiming to naturally enhance sexual performance. Methods Pfizer Global Security coordinated sample collection (all from convenience stores and filling stations in two U.S. metropolitan areas except for seven from U.S. Customs seizures) and liquid chromatography/mass spectrometry examination. Main Outcome Measure Adulteration with synthetic PDE5 inhibitors. Results Ninety-one samples labeled as 58 distinct products and priced from $2.99 to $17.99 were evaluated. Origin/manufacture was claimed as United States (n = 62), apparently Asian (n = 15), and not clearly identified (n = 14). Although no sample claimed to include synthetic substances, 74 (81%) contained PDE5-inhibitor pharmaceutical ingredients, including tadalafil and/or sildenafil (n = 40, of which 18 contained >110% of the highest approved drug product strength) or PDE5-inhibitor analogs (n = 34). Pronounced heterogeneity of contents between samples within individual products indicated minimal quality control during manufacture. Labeling was inadequate (e.g., lacking lot number and/or expiry date) for 17 products (23 samples) and inconsistent between samples within a given product (e.g., in manufacturer, lot number, and/or expiry date) for seven of 17 products having multiple samples. Only 14 samples warned against concomitant nitrate use. Conclusions Ethical pharmaceutical companies are concerned for an unsuspecting public when their products are counterfeited, mislabeled, and illegally offered for sale in an unsafe manner. Because of the dangers of adulteration with synthetic PDE5 inhibitors, absent safety warnings, and lack of quality or consistent manufacture, men with ED unknowingly risk their health by using OTC herbal/natural products that claim to enhance sexual performance. Campbell N, Clark JP, Stecher VJ, Thomas JW, Callanan AC, Donnelly BF, Goldstein I, and Kaminetsky JC. Adulteration of purported herbal and natural sexual performance enhancement dietary supplements with synthetic phosphodiesterase type 5 inhibitors.

To investigate transrenal arteriovenous graft creation in an animal model and to report survival and patency.Arteriovenous grafts were created from the renal artery to the renal vein in 10 swine. Renal access was accomplished with a combined percutaneous and transvascular approach. A reinforced 6-mm polytetrafluoroethylene conduit was tunneled between both flank access points, and stent-grafts were deployed from each of the renal origins into the conduit. Clopidogrel (10 mg per kilogram of body weight) was administered intravenously during the procedure, followed by a daily oral dose (75 mg) for up to 2 weeks. Animals were monitored with auscultation and angiography for up to 1 month; necropsy was performed in all animals.Rapid arteriovenous flow at completion angiography was achieved in eight of 10 animals. Shunts were patent in five of six animals that were followed for 1 month. Diffuse pseudointimal hyperplasia was mild in three of six shunts and moderate in two (focal stenoses). Immediate thrombosis occurred in the first two animals when the clopidogrel bolus was administered after stent-graft deployment. These shunts were recanalized mechanically. Shunts were immediately patent in five of the six remaining shunts when the clopidogrel bolus was administered prior to stent-graft deployment. Complications occurred in four of 10 animals, three of which were euthanized within 1 week. The bowel was traversed in two animals, and renal vein laceration occurred during two procedures because of failure of the stent-graft delivery system.Transrenal arteriovenous graft creation in swine is technically feasible, and long-term patency is possible with antiplatelet therapy.

PURPOSE Alpha-1-antitrypsin (AAT) is the major circulating elastase inhibitor. Deficiency of elastase inhibition leads to emphysema and vascular abnormalities including accelerated neointima. Because recent evidence suggests that tissue AAT levels determine inhibitory function, the authors hypothesize that local tissue-based expression of AAT limits elastase activity sufficiently to guide arterial response to injury. MATERIALS AND METHODS Rabbit common femoral arteries were injured by mechanical overdilation and treated with buffer, viral control, or an adenovirus expressing AAT (Ad/AAT). After 3 and 28 days, intima-to-media (I/M) ratios were evaluated. Additionally, early changes in elastase inhibition potential (3 d), extracellular elastin and collagen content (3 d), and local macrophage and neutrophil infiltration (7 d) were determined. RESULTS Ad/AAT significantly decreased neointima formation after mechanical dilation injury after 28 days: buffer controls exhibited mean I/M ratios of 0.76 ± 0.06, whereas viral controls reached 0.77 ± 0.09; in contrast, Ad/AAT reduced I/M ratios to 0.44 ± 0.06. Both early elastin and collagen content were preserved in the Ad/AAT group relative to controls. The Ad/AAT group also reversed the local inflammation that characterized viral controls. CONCLUSIONS This strategy demonstrates that local increases in elastase inhibition potential promote a neointimaresistant small-caliber artery, which may offer new promise in management of patients undergoing angioplasty.

To evaluate the incidence and management of catheter occlusion in implantable arm ports.Findings were prospectively examined in 391 patients in whom 393 arm ports were placed. The indications for port placement included chemotherapy (n = 347), antibiotic administration (n = 35), combination chemotherapy/antibiotic use (n = 7), transfusion (n = 3), and phlebotomy (n = 1). Of the total catheters, 323 (82.2%) underwent tip modification prior to placement. Malfunctioning catheters were usually treated with urokinase instillation.Three hundred ninety-three devices were implanted with 247 mean days of catheter use (total, 97,256 days; range, 1-694 days). The overall incidence of catheter occlusion was 0.14 per 100 catheter days. A single catheter occlusion occurred in 90 (22.9%) catheters, with a mean of 90.1 days before the event. A second occlusion occurred in 36 (9.2%) of the above catheters, with a mean of 60.1 catheter days before the second event. Eighty-five (24.0%) of the 347 cancer patients had at least one occlusive event, yielding a complication rate of 0.098 per 100 catheter days at risk (95% confidence interval [CI]; 0.079-0.114). Of the 35 patients receiving antibiotics, three (8.6%) had at least one occlusive event. This represented a complication rate of 0.032 per 100 catheter days at risk (95% CI; 0.010-0.061). Seventeen (24.3%) of the nonmodified catheters developed an occlusion versus 72 (22.3%) of the modified (P.05; Fisher exact test). Of the catheters with a first occlusive event, 75 (98.7%) were treated successfully with urokinase instillation. Four (1.0%) patients developed symptomatic subclavian vein thrombosis. No bleeding complications occurred.Catheter occlusion is a common complication of long-term arm port placement, with a significantly higher incidence in the cancer patients in our series (P. 05, Fisher exact test). Catheter tip modification, however, does not considerably affect the incidence of occlusion. Low-dose urokinase therapy is a safe and efficacious treatment of catheter occlusion, obviating the need for catheter removal.

Laceration of the thoracic aorta or brachiocephalic vessels due to blunt trauma is relatively common. In such cases, prompt and accurate diagnosis followed by timely surgery is essential. These injuries typically occur at the aortic isthmus and can usually be readily identified at aortography, which remains the standard of reference for diagnosis. However, numerous anatomic variants that manifest as "lumps" or "bumps" on aortograms can mimic true vascular injury, thereby leading to false-positive or false-negative diagnosis. These variants include aortic spindle, classic or atypical ductal diverticula, and infundibula of the brachiocephalic arteries and adjacent branches or of the right third intercostal artery. Ductus diverticula typically occur at the isthmus and have smooth, uninterrupted margins with gently sloping shoulders. Infundibula are also smoothly marginated but can occur in a variety of locations and generally taper into one or more vessels at their apex. Knowledge of the imaging appearances of these anatomic variants is necessary for correct interpretation of aortograms of the aorta and brachiocephalic vessels in blunt trauma patients.

The main focus of the present study was to define the rotational response of 6-hydroxydopamine-lesioned rats to dopaminergic agonists to separate the partially lesioned rats from those having complete substantia nigra (SN) and ventral tegmental area (VTA) lesions. Animals were challenged by amphetamine and L-DOPA for 10 consecutive weeks. There was a correlation between rotational behavior and extent of midbrain cell loss. Rats with complete SN and

Guanine nucleotides have been examined for their effect on [ 3 H]-[1-(2-thienyl)-cyclohexyl]-piperidine ([ 3 H]TCP) binding to rat forebrain synaptic plasma membranes (SPM). We report that of the series of guanine nucleotides tested, GTP, GDP, 5′-guanylylimidodiphosphate (Gpp(NH)p) and 5′-guanylylmethylenediphosphate (Gpp(CH 2 )p) are significantly more potent at decreasing [ 3 H]TCA binding than GMP, cyclic GMP, and guanosine. GTP, the most potent compound tested, inhibited basal [ 3 H]TCP binding with an IC 50 of 38.7 μM. Stimulation of [ 3 H]TCP binding with either the N-methyl-D-aspartate (NMDA) agonist, L-glutamate, or Mg 2+ was also inhibited by GTP. Addition of GTP resulted in a rightward shift in the glutamate dose-response curve and a decrease in the maximum level of stimulation. The Mg 2+ stimulation of [ 3 H]TCP binding was completely blocked by the addition of GTP. These results, coupled with the previous findings that guanine nucleotides inhibit the binding of L-[ 3 H]glutamate to the NMDA recognition site (Monahan et al., 1988), indicate that guanine nucleotides antagonize NMDA receptor-mediated neurotransmission, at least in part, through their action (direct or indirect) on the NMDA recognition site and thus may be endogenous negative modulators of the NMDA receptor.

A single phage was isolated from a λ gt11 rat brain cDNA library by screening with antibodies prepared against rat renal glutaminase. Partial proteolysis of the fusion protein produced by a lysogen of the isolated phage generated a series of immunoreactive peptides that co-migrated with those derived from the purified brain glutaminase. The cDNA has a single open reading frame which encodes 326 amino acids that are in frame with β-galactosidase. A 72-kDa protein, corresponding in size to the precursor of mitochondrial glutaminase, was immunoprecipitated from the translation products of rat renal mRNA that selectively hybridized to the cDNA. A probe made from the glutaminase cDNA detected an mRNA about 6 kb in length. This mRNA was present in rat brain and normal kidney RNA, increased 6-fold in acidotic kidney RNA, but was not detectable in liver RNA.

Radiation inactivation was used to estimate the molecular weight of the benzodiazepine (BZ), γ-amino-butyric acid (GABA), and associated chloride ionophore (picrotoxinin/barbiturate) binding sites in frozen membranes prepared from rat forebrain. The target size of the BZ recognition site (as defined by the binding of the agonists [3H]diazepam and [3H]flunitrazepam, the antagonists [3H]Ro 15–1788 and [3H]CGS 8216, and the inverse agonist [3H]ethyl-β-carboline-3-carboxylate) averaged 51,000 × 2,000 daltons. The presence or absence of GABA during irradiation had no effect on the target size of the BZ recognition site. The apparent molecular weight of the GABA binding site labelled with [3H]muscimol was identical to the BZ receptor when determined under identical assay conditions. However the target size of the picrotoxinin/barbiturate binding site labelled with the cage convulsant [35S]t-butylbicyclophosphorothionate was about threefold larger (138,000 daltons). The effects of lyophilization on BZ receptor binding activity and target size analysis were also determined. A decrease in the number of BZ binding sites (Bmax) was observed in the nonirradiated, lyophilized membranes compared with frozen membranes. Lyophilization of membranes prior to irradiation at – 135°C or 30°C resulted in a 53 and 151% increase, respectively, in the molecular weight (target size) estimates of the BZ recognition site when compared with frozen membrane preparations. Two enzymes were also added to the membrane preparations for subsequent target size analysis. In lyophilized preparations irradiated at 30°C, the target size for (i-galactosidase was also increased 71% when compared with frozen membrane preparations. In contrast, the target size for glucose-6-phosphate dehydrogenase was not altered by lyophilization. Thus, in some cases lyophilization may lead to an increase in protein target size, possibly due to aggregation of protein subunits. We conclude that in frozen membrane preparations the functional target size of the BZ and GABA binding sites reflects the subunit molecular weights for the BZ/GABA/chloride ionophore receptor complex.

Plasma and brain levels of the dopamine metabolite, homovanillic acid, were measured in rats after acute and chronic treatment with fluphenazine. After acute administration, homovanillic acid levels were increased in the whole frontal cortex, caudate nucleus, nucleus accumbens, anterior cingulate (supragenual) cortex, prefrontal cortex and plasma. Following chronic administration, the effects of single doses of fluphenazine in increasing homovanillic acid were markedly attenuated in the caudate nucleus, nucleus accumbens, the whole frontal cortex, anterior cigulate cortex and plasma, but not in the prefrontal (anteromedial) cortex. Following fluphenazine administration plasma homovanillic acid levels were correlated with homovanillic acid concentrations in whole frontal cortex (r = 0.63, p less than 0.01) and caudate nucleus (r = 0.51, p less than 0.05). Further, prior intracerebroventricular administration of 6-hydroxydopamine prevented the fluphenazine-induced increase in plasma homovanillic acid. These data suggest that in the rat, plasma and brain (caudate nucleus and whole frontal cortex) homovanillic acid levels change in a similar fashion during acute and chronic neuroleptic administration.

Pretreatment of rats in vivo with γ-aminobutyric acid (GABA) agonists and drugs which increase GABA levels in brain leads to an increased affinity of [3H]diazepam binding sites in rat cerebral cortex. These drugs include amino-oxyacetic acid, muscimol, γ-butyrolactone and β-(p-chlorophenyl)-GABA; pentobarbital and thiosemicarbazide are without major effect. Bicuculline and picrotoxin (at high concentrations) reverse this increase in [3H]diazepam binding site affinity.

A 78-year-old man suffered an unusual variant of sweat gland carcinoma of the eyelid. This disorder is seldom recognized, and is frequently confused with inflammation, benign neoplasms, and metastatic carcinomas. On the basis of clinicopathologic and ultrastructural features found by both light and electron microscopy, we diagnosed sweat gland carcinoma of the eyelid. We considered the possibility of metastasis from a primary carcinoma elsewhere in the patient.

An eleven-year experience with intraaortic balloon pumping (IABP) or counterpulsation in 637 patients was analyzed with respect to early and late results. Intraaortic balloon pumping was employed for left ventricular pump failure, for coronary insufficiency, and in association with cardiac operations. Late results were analyzed by follow-up of 283 (93%) of the 304 patients leaving the hospital, and were studied with respect to duration of survival, activity status, occupational status, presence of cardiac symptoms, use of cardiac medications, and presence of lower extremity claudication. Early results were analyzed for hospital survival (304/637 [48%]). Patient complications of IABP included wound infection (1/637 or 0.2%), vascular complications (66/637 or 10.4%), and balloon failure (8/637 or 1.3%). No deaths were attributable to complications of IABP. Survival did not correlate with the duration of IABP. Survival was improved in patients who had revascularization in association with IABP.

This study reviews the experience in a community hospital with aortocoronary bypass in 100 consecutive patients following failed percutaneous transluminal coronary angioplasty (PTCA) in terms of timing of intervention, morbidity, and mortality. Patients undergoing operation within 24 hours of PTCA are defined as the urgent group (68%) and those with intervention at greater than 24 hours, the elective group (32%). Mean interval from PTCA to operation was 43.5 days; among patients with apparently initially successful PTCA and hospital discharge, mean interval to operation was 138 days. Complete revascularization was carried out in all patients using standard techniques. Although the difference was not statistically significant, patients in the urgent group required intraaortic balloon pump support and inotropic infusions more often and experienced greater postoperative blood loss. Significant increases in the use of lidocaine and blood products were noted in the urgent group. The rates of major complications were 54.4% in the urgent group and 18.8% in the elective group. Mortality was 4.4% in the urgent group and 3.1% in the elective group (not significant); all deaths were cardiac related. There were no late deaths among survivors followed for 3 months to 4 years; 86% were in Functional Class I. We conclude that PTCA is a reasonable approach for some patients with ischemic heart disease. However, mandatory urgent aortocoronary bypass in these patients carries an increased morbidity and mortality, and patients should be selected with care.

The pathway of breakdown of membrane-bound benzodiazepine binding sites has been examined with proteolytic enzymes. Photoaffinity labeled benzodiazepine receptors were degraded for varying amounts of time and at varying enzyme concentrations. The properties of fractions both remaining in the membrane and released into the supernatant were examined for their apparent molecular weight by SDS gel electrophoresis. Trypsin treatment converted the 46K subunits of the GABA/BDZ complex which bind 3H-flunitrazepam into 40K and 27.5K fragments which remained in the membrane and finally a small fragment which was released into the supernatant. An endogenous trypsin-like activity in the membrane fractions has similar proteolytic effects on the membrane bound receptor.

An in vivo method for labeling specific benzodiazepine (BDZ) binding sites in brain was developed using intravenously injected [3H]diazepam. Labeling of these sites is blocked by pretreatment of animals with high doses of pharmacologically active BDZs (but not by an inactive BDZ). Using this in vivo binding technique, specific BDZ binding is enhanced by pretreatment of rats with the GABA agonist muscimol or with amino-oxyacetic acid, which increases GABA levels in brain.

The high-affinity binding site for [3H] diazepam has been solubilized from rat brain using 0.5% Lubrol-PX. Using a polyethylene glycol (PEG)-γ-globulin assay, it has been possible to demonstrate solubilization of about 60% of the binding sites in a single step. The solubilized binding site possesses a KD of 11 nM for [3H] diazepam compared to approximately 4 nM for the membrane-bound form, and binding is to a single class of sites. The order of potency of benzodiazepines is identical for the solubilized receptor and the membrane-bound form. Binding of [3H] diazepam is temperature dependent and higher at 4° than 37°C. Both urea and guanidine-HC1 were capable of totally inhibiting binding, and this inhibition was partly reversible; neither sulfhydryl groups nor carbohydrate moieties seem to be important for binding. γ-Aminobutyric acid which enhanced [3H] diazepam binding to membrane fractions was without effect on the solubilized binding site.

Several recent studies in animals and man indicate that corticosteroids may alter catecholaminergic activity in both the peripheral and central nervous systems. We administered 1 mg of the synthetic glucocorticoid, dexamethasone, to 12 drug-free healthy volunteers and measured plasma homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol (MHPG). Dexamethasone was administered at 11 p.m. and blood was collected at 4 p.m. on the preceding and subsequent days. Dexamethasone administration resulted in a significant increase in plasma HVA but did not consistently affect MHPG. All subjects showed a suppression of serum cortisol to values less than 5 micrograms/dl while prolactin levels were unaltered. In an additional group of nine volunteers, we administered 2 mg of dexamethasone and observed a similar increase in plasma HVA without change in plasma MHPG, indicating a selective effect on dopamine metabolism. Implications of these findings for an understanding of the neurochemical and behavioral changes seen with steroid administration and in explaining previous results on plasma MHPG/HVA ratios in delusional depression are discussed.

Glutamic acid decarboxylase (GAD) mRNA was quantified in different regions of rat brain using an antisense RNA probe (ribo-probe) prepared from a cloned feline cDNA. In all brain regions studied a single band of GAD mRNA of approximately 3.7 kb was detected. The level of GAD mRNA was highest in the cerebellum, followed by the hypothalamus greater than thalamus greater than striatum greater than hippocampus greater than frontal cortex = parietal cortex greater than or equal to medulla = pons. Since GAD has been previously localized to intrinsic neurons of the striatum, we examined the effects of intrastriatal kainic acid administration on striatal GAD mRNA. The level of GAD mRNA in the kainic acid-lesioned striatum was reduced by 70-75% when compared to the contralateral (unlesioned) striatum. In contrast, the level of glutamine synthetase (an enzyme localized to glia) mRNA was increased approximately 290% in the kainic acid-lesioned striatum. There were no significant differences in GAD mRNA levels between the ipsilateral and contralateral cerebral cortices and hippocampi of rats injected with intrastriatal kainic acid.