Phase I Study of ORIC-101, a Glucocorticoid Receptor Antagonist, in Combination with Enzalutamide in Patients with Metastatic Castration-resistant Prostate Cancer Progressing on Enzalutamide

PURPOSE

Increased glucocorticoid receptor (GR) signaling is a proposed compensatory mechanism of resistance to androgen receptor (AR) inhibition in metastatic castration-resistant prostate cancer (mCRPC). ORIC-101 is a potent and selective orally-bioavailable GR antagonist.

PATIENTS AND METHODS

Safety, pharmacokinetic/pharmacodynamic, and antitumor activity of ORIC-101 in combination with enzalutamide were studied in patients with mCRPC progressing on enzalutamide. ORIC-101 doses ranging from 80 to 240 mg once daily were tested in combination with enzalutamide 160 mg once daily. Pharmacokinetics/pharmacodynamics was assessed after a single dose and at steady state. Disease control rate (DCR) at 12 weeks was evaluated at the recommended phase 2 dose (RP2D).

RESULTS

A total of 41 patients were enrolled. There were no dose-limiting toxicities and the RP2D was selected as 240 mg of ORIC-101 and 160 mg of enzalutamide daily. At the RP2D, the most common treatment-related adverse events were fatigue (38.7%), nausea (29.0%), decreased appetite (19.4%), and constipation (12.9%). Pharmacokinetic/pharmacodynamic data confirmed ORIC-101 achieved exposures necessary for GR target engagement. Overall, for 31 patients treated at the RP2D, there was insufficient clinical benefit based on DCR (25.8%; 80% confidence interval: 15.65-38.52) which did not meet the prespecified target rate, leading to termination of the study. Exploratory subgroup analyses based on baseline GR expression, presence of AR resistance variants, and molecular features of aggressive variant prostate cancer suggested possible benefit in patients with high GR expression and no other resistance markers, although this would require confirmation.

CONCLUSIONS

Although the combination of ORIC-101 and enzalutamide demonstrated an acceptable tolerability profile, GR target inhibition with ORIC-101 did not produce clinical benefit in men with metastatic prostate cancer resistant to enzalutamide.

The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

The implementation and evaluation of a mentoring program for Bachelor of Midwifery students in the clinical practice environment

AIM

To describe the implementation and evaluation of a midwife/midwifery student-mentoring program in one Local Health District in Sydney NSW Australia.

BACKGROUND

Evidence suggests well designed and supported midwife/midwifery student mentorship programs can make a difference to the clinical placement experiences and attrition rates of midwifery students.

DESIGN

In the evaluation of the mentoring program, we used surveys, focus groups and individual interviews.

METHODS

Eighty-six participants, including midwife mentors, midwifery students, non-mentor midwives and midwifery managers participated in the evaluation. Quantitative data were analysed using descriptive statistics and qualitative data, content analysis.

RESULTS

The mentoring program increased midwives' mentoring skills and was beneficial to their professional growth and leadership skills. Students reported positive outcomes including someone to talk to, emotional support and a sense of belonging. Mentoring programs require structure, mentor training, organisational support and transparency.

CONCLUSION

The mentoring program provided benefits to both midwifery mentors and students and demonstrated the value of a structured and supported mentoring program for midwifery students.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Biomarker results supporting selection of RP2D from a phase 1b study of ORIC-101, a glucocorticoid receptor antagonist, in combination with nab-paclitaxel in patients with advanced solid tumors

3110

Background: Preclinical studies have shown that activation of the glucocorticoid receptor (GR) leads to resistance to chemotherapeutics (eg taxanes) and antiandrogens across multiple tumor types, while GR inhibition enhances therapeutic efficacy. ORIC-101 is a potent, selective, and orally bioavailable small molecule GR antagonist undergoing clinical development in combination with nab-paclitaxel in patients with advanced solid tumors and in combination with enzalutamide in patients with metastatic prostate cancer. Methods: 21 patients were enrolled in the dose escalation portion of the phase 1b study, which evaluated both intermittent (5 days on, 2 days off for 21 days) and continuous dosing regimens of ORIC-101 across 5 cohorts (NCT03928314). Tumor tissue was obtained pre-treatment for 19 out of 21 patients, and on study or at the end of treatment for 11 patients. GR protein status was retrospectively evaluated using a proprietary IHC assay optimized for staining nuclear GR in the epithelial compartment of major tumor type tissues. Biopsies were also profiled with RNA-seq to evaluate a proprietary GR activation signature as a potentially predictive and pharmacodynamic (PD) biomarker. Blood-derived peripheral blood mononuclear cells (PBMCs) were collected for 20 patients along with the pre-treatment biopsy, in the morning of days 1, 5 and/or 8 of Cycle 1, and 2.5 or 6 hours after ORIC-101 administration. Blood cortisol levels were also simultaneously measured. PD modulation in PBMCs was assessed by RT-qPCR for biomarkers FKBP5, GILZ and PER1, selected for their consistent stimulation by GR and reversal with ORIC-101 in preclinical studies and observed PD modulation in healthy volunteers administered ORIC-101. Results: Nuclear GR protein was detected in most pre-treatment biopsies regardless of tumor type, and on treatment reduction of GR protein was observed across dose levels. At physiological systemic cortisol levels, ORIC-101 demonstrated PD suppression in PBMCs on days 1, 5 and 8 in the majority of patients. Cortisol levels increased post-dose in these patients due to negative feedback between cortisol and GR. Steady-state target engagement was not consistently demonstrated with the intermittent regimen. In healthy volunteer studies of ORIC-101, steady-state target suppression was consistently achieved after 7 consecutive daily doses of 200 or 350 mg of ORIC-101. Thus, continuous ORIC-101 administration was selected as the recommended phase 2 dose (RP2D) regimen, aimed at achieving sustained GR suppression for optimal chemotherapy re-sensitization. Conclusions: Biomarker data from patients enrolled in the phase 1b study provide evidence of on-target tumor cell eradication and PD modulation and support the RP2D and the tumor types selected for the ongoing dose expansion portion of the study. Clinical trial information: NCT03928314.

Initial results from a phase 1b study of ORIC-101, a glucocorticoid receptor antagonist, in combination with nab-paclitaxel in patients with advanced solid tumors

2553

Background: ORIC-101 is a potent and selective, orally bioavailable, small molecule antagonist of the glucocorticoid receptor (GR). Preclinical studies have demonstrated that activation of GR signaling leads to decreased responsiveness to chemotherapeutics (eg, taxanes) and antiandrogens across multiple tumor types. Mechanistically, ORIC-101 inhibits GR transcriptional activity and blocks the prosurvival signals mediated by the activated nuclear hormone receptor. Methods: A 3+3 dose escalation design was used to assess safety, pharmacokinetics (PK), pharmacodynamics (PD), and select the Recommended Phase 2 Dose (RP2D) of ORIC-101 in combination with nab-paclitaxel (nab-pac; NCT03928314). ORIC-101 doses ranging from 80 to 240 mg once daily, given either intermittently or in a continuous dosing regimen, were evaluated in combination with weekly nab-pac at 75 or 100 mg/m2. Plasma PK and PD biomarkers were assessed on day 1 and after repeat dosing. PD modulation in blood-derived peripheral blood mononuclear cells (PBMCs) was assessed by RT-qPCR for GR target genes. Antitumor activity was assessed by RECIST v1.1. Results: 21 patients with 10 different solid tumors, with and without a prior taxane, were treated in 5 cohorts. ORIC-101 exposure increased with dose, with no evidence for drug-drug interaction with nab-pac. In the initial cohort at 240 mg ORIC-101 and 100 mg/m2 nab-pac, 2 patients experienced dose limiting toxicities (DLTs) of Grade 3 fatigue and Grade 4 neutropenia/thrombocytopenia, respectively. No further DLTs were observed in subsequent cohorts and the RP2D was established as 160 mg ORIC-101 dosed once daily continuously for 21 days with nab-pac 75 mg/m2 given on days 1, 8, and 15 of each 28-day cycle, without requirement for prophylactic granulocyte colony-stimulating factor (G-CSF). The most common (> 15%), all grade treatment-related adverse events (AEs) were nausea (38%), diarrhea (33%), fatigue (29%), leukopenia (29%), neutropenia (29%), anemia (24%), and 19% of patients had increased liver function tests and alopecia. Biomarker data demonstrated ORIC-101-induced reduction in GR target gene expression in PBMCs, indicating PD modulation at all dose levels of ORIC-101. Preliminary antitumor activity was observed in 3 taxane-refractory patients with breast, endometrial, and pancreatic cancers. Conclusions: The combination of ORIC-101 and nab-paclitaxel demonstrated an acceptable tolerability profile and does not require prophylactic G-CSF. PK and PD showed no evidence of drug-drug-interaction and demonstrated GR target inhibition. Preliminary antitumor activity was observed in patients with solid tumors that previously progressed on a taxane-containing regimen. Dose expansion is ongoing at the RP2D in dedicated pancreatic, ovarian, triple negative breast cancers, and tissue-agnostic cohorts. Clinical trial information: NCT03928314.

Simultaneous pelvic exenteration and liver resection for primary rectal cancer with synchronous liver metastases: results from the PelvEx Collaborative

AIM

At presentation, 15-20% of patients with rectal cancer already have synchronous liver metastases. The aim of this study was to determine the surgical and survival outcomes in patients with advanced rectal cancer who underwent combined pelvic exenteration and liver (oligometastatic) resection.

METHOD

Data from 20 international institutions that performed simultaneous pelvic exenteration and liver resection between 2007 and 2017 were accumulated. Primarily, we examined perioperative outcomes, morbidity and mortality. We also assessed the impact that margin status had on survival.

RESULTS

Of 128 patients, 72 (56.2%) were men with a median age of 60 years [interquartile range (IQR) 15 years]. The median size of the liver oligometastatic deposits was 2 cm (IQR 1.8 cm). The median duration of surgery was 406 min (IQR 240 min), with a median blood loss of 1090 ml (IQR 2010 ml). A negative resection margin (R0 resection) was achieved in 73.5% of pelvic exenterations and 66.4% of liver resections. The 30-day mortality rate was 1.6%, and 32% of patients had a major postoperative complication. The 5-year overall survival for patients in whom an R0 resection of both primary and metastatic disease was achieved was 54.6% compared with 20% for those with an R1/R2 resection (P = 0.006).

CONCLUSION

Simultaneous pelvic exenteration and liver resection is feasible, with acceptable morbidity and mortality. Simultaneous resection should only be performed where an R0 resection of both pelvic and hepatic disease is anticipated.

A spectrometer for ultrashort gamma-ray pulses with photon energies greater than 10 MeV

We present a design for a pixelated scintillator based gamma-ray spectrometer for non-linear inverse Compton scattering experiments. By colliding a laser wakefield accelerated electron beam with a tightly focused, intense laser pulse, gamma-ray photons up to 100 MeV energies and with few femtosecond duration may be produced. To measure the energy spectrum and angular distribution, a 33 × 47 array of cesium-iodide crystals was oriented such that the 47 crystal length axis was parallel to the gamma-ray beam and the 33 crystal length axis was oriented in the vertical direction. Using an iterative deconvolution method similar to the YOGI code, modeling of the scintillator response using GEANT4 and fitting to a quantum Monte Carlo calculated photon spectrum, we are able to extract the gamma ray spectra generated by the inverse Compton interaction.

Bradykinin receptor blockade restores the baroreflex control of renal sympathetic nerve activity in cisplatin-induced renal failure rats

AIM

This study investigated the effect of renal bradykinin B1 and B2 receptor blockade on the high- and low-pressure baroreceptor reflex regulation of renal sympathetic nerve activity (RSNA) in rats with cisplatin-induced renal failure.

METHODS

Cisplatin (5 mg/kg) or saline was given intraperitoneally 4 days prior to study. Following chloralose/urethane anaesthesia, rats were prepared for measurement of mean arterial pressure (MAP), heart rate and RSNA and received intrarenal infusions of either Lys-[des-Arg⁹ , Leu⁸ ]-bradykinin (LBK), a bradykinin B1 receptor blocker, or bradyzide (BZ), a bradykinin B2 receptor blocker. RSNA baroreflex gain curves and renal sympatho-inhibitory responses to volume expansion (VE) were obtained.

RESULTS

In the control and renal failure groups, basal MAP (89 ± 3 vs. 80 ± 8 mmHg) and RSNA (2.0 ± 0.3 vs. 1.7 ± 0.6 μV.s) were similar but HR was lower in the latter group (331 ± 8 vs. 396 ± 9 beats/min). The baroreflex gain for RSNA in the renal failure rats was 39% (P < 0.05) lower than the control but was restored to normal values following intrarenal infusion of BZ, but not LBK. VE had no effect on MAP or HR but reduced RSNA by some 40% (P < 0.05) in control but not renal failure rats. Intrarenal LBK infusion in the renal failure rats normalized the VE induced renal sympatho-inhibition whereas BZ only partially restored the response.

CONCLUSION

These findings suggest that pro-inflammatory bradykinin acting at different receptors within the kidney generates afferent neural signals which impact differentially within the central nervous system on high- and low-pressure regulation of RSNA.

Routine laparoscopic repair of primary unilateral inguinal hernias--a viable alternative in the day surgery unit?

In September 2004 the NICE institute revised its guidelines on the management of primary inguinal hernias to include laparoscopic repair of unilateral hernias. While published trials have confirmed the equal efficacy of the two approaches, it is not clear what impact a switch to laparoscopic repairs would have on resources and patient throughput in a Day Surgery Unit.

METHOD

All elective hernia repairs performed in a one-year period were considered. Data were obtained from operation notes, discharge summaries and out-patient records. Operating times are routinely documented in theatre.

RESULTS

Of the 351 operations studied, 150 were performed laparoscopically predominantly by an extraperitoneal (TEP)approach. Six required conversion to an open procedure. There was no significant difference in operating times, total theatre time or recovery room times between the two groups (51 min, 75 min and 34 min for the laparoscopic group and 53 min, 74 min and 31 min for the open repair group). Among the laparoscopic repair group there were 48 bilateral hernias and 20 recurrent hernias while 190 of the 201 open repairs were for primary unilateral hernias. Rates of overnight stay and immediate complications were similar between the groups though haematoma was more common following open repair (7 vs 2).

CONCLUSIONS

There is no difference in theatre times, immediate complication rates or rates of overnight stay between open and laparoscopic repair of inguinal hernia. Routine laparoscopic repair of primary unilateral inguinal hernia is a viable alternative within the Day Surgery Unit.

Overlapping CRE and E-box promoter elements can independently regulate COX-2 gene transcription in macrophages

Macrophage cyclooxygenase-2 (COX-2) transcription is mediated through the collaboration of different promoter elements. Here, the role of an overlapping cyclic AMP responsive element (CRE)/E-box was investigated. Nuclear proteins bound both the CRE and E-box, which synergized with other promoter elements to induce COX-2 transcription. Endotoxin induced binding of nuclear proteins to the CRE and E-box and each element independently induced higher COX-2 transcription levels than the overlapping CRE/E-box. Transcription factors associated with the CRE binding complex included c-Jun and CRE binding protein and with the E-box binding complex USF-1; their overexpression significantly induced COX-2 transcription. Therefore, both CRE and E-box promoter elements regulate COX-2 transcription in macrophages.

Cathepsin S regulates the expression of cathepsin L and the turnover of gamma-interferon-inducible lysosomal thiol reductase in B lymphocytes

Loading of antigenic peptide fragments on major histocompatibility complex class II molecules is essential for generation of CD4(+) T cell responses and occurs after cathepsin-mediated degradation of the invariant chain chaperone molecule. Cathepsins are expressed differentially in antigen presenting cells, and mice deficient in cathepsin S or cathepsin L exhibit severely impaired antigen presentation in peripheral lymphoid organs and the thymus, respectively. To determine whether these defects are due solely to the block in invariant chain cleavage, we used cathepsin-deficient B cells to examine the role of cathepsins S and B in the degradation of other molecules important in the class II presentation pathway. Our data indicate that neither cathepsin S nor B is critical for H-2M degradation or processing of precursor gamma-interferon-inducible lysosomal thiol reductase (GILT) to a mature thiol reductase, but suggest a role for cathepsin S in the turnover of mature GILT and in regulating levels of mature cathepsin L protein in B cells. Despite the presence of mature cathepsin L protein, no enzyme activity could be detected in B cells or dendritic cells. These experiments suggest a novel mechanism by which these functionally important enzymes may be regulated.

Breast cancer screening for older women with intellectual disability living in community group homes

Breast cancer is one of the commonest cancers to affect women. Present health service guidelines call for screening and mammography for all women aged between 50 and 65 years in an effort to increase early detection and improve survival rates. Nulliparity is one of the associated risk factors for breast cancer. Women with intellectual disability (ID) are increasing in longevity and are frequently nulliparous, and therefore, they are at increased risk of developing breast cancer. The aim of the present study was to review the uptake and knowledge of women with ID living in the community of breast screening programmes. A postal survey of women aged > or = 50 years with ID living in community group homes was used to gather data. Only one-third of the women carried out regular breast examination and a similar proportion had received invitations to mammography. General practitioners and practice nurses were currently playing very minor roles in breast screening these women. Primary health care professionals may be missing opportunistic health promotion opportunities and the support services for women with ID living in the community could be provided with better training and resources to improve breast cancer screening in this vulnerable group.

Helicobacter pylori: has the killer escaped from the institution? A possible cause of increased stomach cancer in a population with intellectual disability

Advancing knowledge of the existence of Helicobacter pylori and its association with gastrointestinal tract malignancy, and previous research showing higher-than-expected gastrointestinal tract malignancy in institutionalized adults with intellectual disability (ID) prompted a review of all deaths as a result of cancer in the Stoke Park group of hospitals for people with ID between 1946 and 1996. A 50-year, retrospective case note analysis of all deaths from cancer in an institution for people with ID was undertaken. Death from stomach cancer accounted for up to 48% of all cancer deaths. A further 25 residents had died of perforated stomach ulcers. The higher proportion of deaths specifically caused by stomach cancer in a population with ID has not been noted previously. It is postulated that the high levels of H. pylori infection found in institutionalized populations may be instrumental in this higher mortality rate and that the closure of the institutions without evaluation of H. pylori status transfers the problem unresolved to the community. Existing guidelines for the screening and eradication of H. pylori developed for the general population are inadequate when applied to people with ID, and therefore, the value of population screening and mass eradication programmes is explored.

Recognition and source memory for pictures in children and adults

The present experiment investigated the developmental aspects of source compared to item memory. College students and 7-8-year-old children viewed pictures drawn in red or green during a study phase, and were asked either to remember the pictures for a subsequent recognition test, or to remember both the pictures and their associated colors for a subsequent source memory test. In the test phase, new and old pictures were presented in black. In the recognition task, participants were asked to make binary old/new recognition judgments, while in the source task, they were asked to make trinary old-green/old-red/new source judgements. Performance on all tasks improved with increasing age, but the age difference for source was much larger than that for item memory. It has been suggested that the frontal lobes play a critical role in the retrieval of source information, and that this brain region relative to the medial temporal lobes continues to develop into late adolescence. Thus, it is possible that immaturity of the frontal lobes may be causally related to the children's lower performance on the source memory task.

Prospective evaluation of the morbidity of axillary clearance for breast cancer

BACKGROUND

Axillary clearance, despite its morbidity, retains an essential role in the management of patients with breast cancer. The aim of this prospective study was to document the development of arm swelling and limitation of shoulder movement following complete axillary clearance.

METHODS

One hundred patients who had axillary clearance to level III, for treatment of breast cancer, were followed prospectively for over 1 year. Arm volumes were measured using an optoelectronic volometer and shoulder movements with a goniometer.

RESULTS

Ten patients had significant arm swelling at 1 year. The swelling was mild in eight and moderate in two. No patient developed severe swelling. Reduced arm movements were noted in the first week after operation but had returned to normal at 6 months.

CONCLUSION

This study provided accurate documentation of the morbidity associated with axillary clearance, together with a reproducible method of arm volume measurement.

Helicobacter pylori and the learning disabled

Those with a learning disability previously cared for in institutions have now been discharged into smaller community homes. This has meant that an increased burden has been placed on general practitioners (GPs) to evaluate and treat those who have symptoms that may be difficult to interpret. This report presents the prevalence of Helicobacter pylori in those still awaiting discharge and discusses the possible symptoms that GPs may encounter.

Role of biotin-containing membranes and nuclear distribution in differentiating human endometrial cells

Human Ishikawa endometrial cells form domes when confluent monolayers are stimulated with fresh fetal bovine serum. Extensive structural and biochemical changes have been detected during the approximately 30 h differentiation period. The earliest detectable change involves the formation of multinucleated structures and the appearance of "granules" that stain for biotin within those structures. Nuclei become associated with each other and are ultimately enclosed within a biotin-containing membrane. Aggregated membrane-sheathed nuclei and the cells containing them begin to elevate from the dish as biotin staining becomes apparent in apical membranes. The elevated structures are called predomes and consist of one or more very large cells containing the sheathed nuclei. Apical membranes of these unusual cells extend far out into the medium in structures that resemble endometrial pinopods. A lumen under the elevated cells fills with transcytosed fluid. As differentiation proceeds, highly concentrated chromatin material that was flattened against apical and lateral membranes of the predome cells begins to disperse. Small mononuclear cells evolve from larger predome cells. Apical membranes of predome and dome cells continue to stain for biotin. Gel electrophoresis of SDS-solubilized biotin-containing membranes, followed by Western blot analysis using avidin-linked peroxidase, resulted in three stained bands with molecular weights similar to those of the mitochondrial carboxylases: propionyl carboxylase, methylmalonyl carboxylase, and pyruvate carboxylase.

A comparison of purging and nonpurging eating-disordered outpatients: mediating effects of weight and general psychopathology

OBJECTIVES

The present study compared purging and nonpurging eating-disordered outpatients on key behavioral and psychological features of their disorder. It also investigated the possible mediating effects of current level of depression, anxiety or general psychopathology, and current weight on differences between purgers and nonpurgers.

METHOD

Seventy-seven patients from an outpatient eating disorder clinic who purged were compared to 48 clinic patients who did not purge on measures of eating behavior disturbances and specific psychopathology while controlling for weight, level of depression, anxiety, and general distress.

RESULTS

Purgers reported significantly more eating behavior disturbance and higher scores on measures of specific psychopathology than the nonpurgers. These differences were unrelated to current weight, level of anxiety, or general distress. However, severity of depression did moderate some of the difference between the groups.

CONCLUSION

These data provide further support for the proposition that purging is a distinctive clinical marker in all types of eating-disordered patients.

The effect of presemantic acoustic adaptation on semantic "satiation"

A decrement in the strength of the meaning of a word after rapid repetition of that word has been called "semantic satiation." This study asked whether this "satiation" might be produced by presemantic acoustic adaptation. Category words were utilized to prime the meaning of target words. The adaptation or "satiation" procedure, 30 rapid repetitions of the primes, was compared with a control condition of 3 repetitions. Participants listened to a series of prime words, each repeated by either the same speaker or many speakers, and then made semantic decisions on target words. When all the repetitions of a prime word are produced by the same speaker, presemantic and semantic repetitions are confounded. When the repetitions are produced by different speakers, presemantic acoustic repetition is abolished. A semantic decrement was detected with single-speaker, but not with multiple-speaker, repetitions of prime words. This study concluded that the semantic "satiation" observed here was a decrement in the activation level of semantic representations induced by presemantic acoustic adaptation.

Released chromatin: linearized DNA for high resolution fluorescence in situ hybridization

Free DNA was prepared from routinely harvested and fixed cells for high resolution FISH mapping using either a sodium hydroxide/ethanol mixture or 70% formamide. Hybridization signals from cosmid probes appeared as extended lines. The average length of signals on DNA prepared with sodium hydroxide was significantly greater than with formamide. A set of overlapping cosmids from the HLA class II region was used to determine how precisely the actual overlap or gap between probes can be calculated from the measured overlap or gap between their signals. Lengths of the probe signals and their known kilobase lengths were used as an internal ruler. The mean values calculated from the measured length from 30 or more signals for each probe pair showed remarkable conformity with the known kilobase lengths of their overlaps and gaps. Immediately adjacent probes could also be ordered on the released DNA. These simple procedures dramatically increase the speed with which relationships between probes can be determined during contig construction.

Epicardial sites for vagal mediation of sinoatrial function

The posterior atrial fat pad (PAFP) has been described as the probable anatomic location of parasympathetic ganglia mediating sinoatrial (SAN) and atrioventricular nodal function in the mammalian heart. This contrasts with recent localizations of such control elements in the pulmonary vein fat pad (PVFP) and in fatty tissues overlying the junction of inferior vena cava-inferior left atrium (IVC-ILA), respectively. Short bursts (5-8 pulses/burst, 3 bursts/train) of electrical current (1-16 Hz, 400 ms, 1-5 mA) applied directly to the ventral right atrial epicardium via a concentric bipolar electrode (separation 0.3-0.6 mm) during the atrial muscle refractory period, activated subepicardial postganglionic pathways from PVFP and entering the SAN; identical stimulation of dorsal right atrial epicardium between PAFP and SAN excited few or no fiber pathways controlling SAN discharge rate or patterns. In a second series of experiments, injection of a neuronal marker (Fast Blue) into and around SAN, with time (5-10 days) allowed for retrograde transport, resulted in staining of many soma in PVFP but none in IVC-ILA or PAFP. These data strongly affirm the primary, and perhaps exclusive, localization of ganglia that mediate parasympathetic regulation of SAN function in PVFP of the dog's heart, with little or no such participation by ganglia within PAFP or IVC-ILA.

Surgical interruption of postganglionic innervation of the sinoatrial nodal region

Recent experiments have revealed synapses that selectively mediate right and left vagal regulation of sinoatrial function in the fat pad overlying and surrounding the right pulmonary vein complex. However, precise vagal postganglionic pathways to the sinoatrial region have remained obscure. Such pathways, including critically important neural inputs to sinoatrial and atrioventricular nodal regions, may be vulnerable to surgical approaches to atrial or intracardiac repair. The present experiments seek to delineate specific autonomic pathways to the sinoatrial region of the canine heart. The distal ends of the cut right and left cervical vagi and the right and left ansae subclaviae were electrically stimulated (10 to 20 Hz, 1 msec, 2 to 3 V) before and after surgical incisions were placed. Cut No. 1 was made longitudinally along the ventral caval surface from the pericardial reflection caudally to the pulmonary vein fat pad, cut No. 2 was made from the caudal end of cut No. 1 transversely across the sulcus terminalis to a point midway across the anterior (ventral) surface of the right atrium. Each incision was closed with 4-0 silk, with care being taken to avoid injury to either the sinoatrial nodal or the pulmonary fat pad regions. In four of seven animals, these two incisions totally interrupted vagal input to the sinoatrial node, whereas in the remaining three dogs a residual inhibitory influence remained. These residual fibers were surgically ablated by excision of globular fat pads situated on the rostrodorsal surfaces of the right superior pulmonary vein, suggesting a dorsorostral route into the interatrial septum and thence to the sinoatrial node. There was little or no interruption of either right or left vagal input to the atrioventricular nodal region; sympathetic supplies to both sinoatrial nodal and atrioventricular nodal regions remained essentially intact after the two incisions. Thus the major parasympathetic postganglionic projections to the sinoatrial node in the dog heart are by way of the free wall of the right atrium and are vulnerable to surgical interventions in this portion of the heart.

Assessing cultured colonies automatically

The number of colonies formed by macrophage colony-forming cells and high proliferation potential colony-forming cells was assessed by an image processor. The processor counted and sized colonies accurately, reproducibly, rapidly (2 s/dish) and objectively. The processor also measured the amount of light (in grey levels) the colonies transmitted. The optical density of a colony (the sum of its grey levels) was related to its cellularity. Thus the image processor compared both the number of colonies in samples and their cellularity. Samples of marrow containing high proliferation potential colony-forming cells of different proliferative capacity were prepared by injecting fluorouracil into mice and collecting their marrow 2-10 days later (marrow samples called FU2-FU10). These samples were cultured with one of three sources of synergistic factor titrated over seven dilutions. Colonies contained approx. 5 X 10(4) cells after 11 days culture but the way that FU2-FU10 marrow grew depended on the interval between treating donors with fluorouracil and collecting their marrow. Samples collected 2-4 days after fluorouracil formed more colonies containing more cells with small increases of synergistic factor whereas samples collected after 8-10 days did neither. It was important to culture samples of marrow with the appropriate synergistic factor for the interval after fluorouracil. Factor(s) derived from the 5637 cell line acted optimally on high proliferation potential colony-forming cells in samples collected 2-8 days after fluorouracil, and factor(s) derived from Wehi 3B cells on high proliferation potential colony-forming cells in samples collected 6-10 days after fluorouracil. Factor(s) derived from placental conditioned medium acted well on samples collected between 2 and 10 days. The proliferative capacity of samples of marrow could also be compared by estimating growth curves for high proliferation potential colony-forming cells in samples collected at successive intervals after fluorouracil.