Pharmacokinetics and effect on renal function and average daily gain in lambs after castration and tail docking, of firocoxib and meloxicam

AIMS

To evaluate and compare the pharmacokinetics of IM and oral firocoxib, and IM meloxicam, and detect their effect on renal function and average daily gain (ADG) in lambs undergoing tail docking and castration.

METHODS

Seventy-five male Romney lambs, aged 3-6 weeks, were randomised into five treatment groups (n = 15 per group): IM firocoxib (1 mg/kg); oral firocoxib (1 mg/kg); IM meloxicam (1 mg/kg); normal saline (approximately 2 mL, oral); or sham. Following the treatment administration, hot-iron tail docking and rubber ring castration were performed in all groups except the sham group, which did not undergo the procedures, but the animals were handled in the same manner as castrated and tail docked lambs. Blood samples were collected before and 1, 2, 4, 6, 8, 24, 48, 72, 96 and 120 hours after treatment administration, and drug concentrations in plasma were quantified by liquid chromatography and mass spectrometry. Plasma urea and creatinine concentrations were determined at a commercial laboratory. Lamb body weights were recorded before and 2, 4 and 8 weeks after tail docking and castration. The pharmacokinetic analysis was carried out using a non-compartmental approach. Between-group and between-time-point differences were compared using mixed model analyses.

RESULTS

There was no evidence for a difference in plasma elimination half-life between firocoxib given IM (LSM 18.6 (SE 1.4) hours), firocoxib given orally (LSM 18.2 (SE 1.4) hours), and meloxicam given IM (LSM 17. 0 (SE 1.4) hours). Firocoxib (IM) had a significantly greater volume of distribution (LSM 3.7 (SE 0.2) L/kg) than IM meloxicam (LSM 0.2 (SE 0.2) L/kg). Lambs in the meloxicam group had higher (p < 0.05) plasma urea and creatinine concentrations than those in the firocoxib, saline and sham groups. Lambs' ADG was decreased (p < 0.01) compared to the other treatment groups in the 0-2 week period following meloxicam administration.

CONCLUSIONS AND CLINICAL RELEVANCE

Both formulations of firocoxib had a long plasma elimination half-life and large volume of distribution. There was a transient reduction in ADG in the meloxicam group, possibly due to mild renal toxicity. Comparative studies on dose-response effects of firocoxib and meloxicam in lambs following the procedures are required.Abbreviations: ADG: Average daily gain; Cmax: Maximum concentration; COX: Cyclooxygenase; LOD: Limit of detection; NSAID: Non-steroidal anti-inflammatory drugs; CL: Plasma clearance; T1/2el: Plasma elimination half-life; Tmax: Time to achieve Cmax; Vd: Volume of distribution.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Bi-specific tenascin-C and fibronectin targeted peptide for solid tumor delivery

Oncofetal fibronectin (FN-EDB) and tenascin-C C domain (TNC-C) are nearly absent in extracellular matrix of normal adult tissues but upregulated in malignant tissues. Both FN-EDB and TNC-C are developed as targets of antibody-based therapies. Here we used peptide phage biopanning to identify a novel targeting peptide (PL1, sequence: PPRRGLIKLKTS) that interacts with both FN-EDB and TNC-C. Systemic PL1-functionalized model nanoscale payloads [iron oxide nanoworms (NWs) and metallic silver nanoparticles] homed to glioblastoma (GBM) and prostate carcinoma xenografts, and to non-malignant angiogenic neovessels induced by VEGF-overexpression. Antibody blockage experiments demonstrated that PL1 tumor homing involved interactions with both receptor proteins. Treatment of GBM mice with PL1-targeted model therapeutic nanocarrier (NWs loaded with a proapoptotic peptide) resulted in reduced tumor growth and increased survival, whereas treatment with untargeted particles had no effect. PL1 peptide may have applications as an affinity ligand for delivery of diagnostic and therapeutic compounds to microenvironment of solid tumors.

Untargeted metabolic profiling of dogs with a suspected toxic mitochondrial myopathy using liquid chromatography-mass spectrometry

'Go Slow myopathy' (GSM) is a suspected toxic myopathy in dogs that primarily occurs in the North Island of New Zealand, and affected dogs usually have a history of consuming meat, offal or bones from wild pigs (including previously frozen and/or cooked meat). Previous epidemiological and pathological studies on GSM have demonstrated that changes in mitochondrial structure and function are most likely caused by an environmental toxin that dogs are exposed to through the ingestion of wild pig. The disease has clinical, histological and biochemical similarities to poisoning in people and animals from the plant Ageratina altissima (white snakeroot). Aqueous and lipid extracts were prepared from liver samples of 24 clinically normal dogs and 15 dogs with GSM for untargeted liquid chromatography-mass spectrometry. Group-wise comparisons of mass spectral data revealed 38 features that were significantly different (FDR<0.05) between normal dogs and those with GSM in aqueous extracts, and 316 significantly different features in lipid extracts. No definitive cause of the myopathy was identified, but alkaloids derived from several plant species were among the possible identities of features that were more abundant in liver samples from affected dogs compared to normal dogs. Mass spectral data also revealed that dogs with GSM have reduced hepatic phospholipid and sphingolipid concentrations relative to normal dogs. In addition, affected dogs had changes in the abundance of kynurenic acid, various dicarboxylic acids and N-acetylated branch chain amino acids, suggestive of mitochondrial dysfunction.

Use of test accuracy study design labels in NICE's diagnostic guidance

BACKGROUND

A variety of study designs are available to evaluate the accuracy of tests, but the terms used to describe these designs seem to lack clarity and standardization. We investigated if this was the case in the diagnostic guidance of the National Institute of Care and Health Excellence (NICE), an influential source of advice on the value of tests.

OBJECTIVES

To describe the range of study design terms and labels used to distinguish study designs in NICE Diagnostic Guidance and the underlying evidence reports.

METHODS

We carefully examined all NICE Diagnostic Guidance that has been developed from inception in 2011 until 2018 and the corresponding diagnostic assessment reports that summarized the evidence, focusing on guidance where tests were considered for diagnosis. We abstracted labels used to describe study designs and investigated what labels were used when studies were weighted differently because of their design (in terms of validity of evidence), in relevant sections. We made a descriptive analysis to assess the range of labels and also categorized labels by design features.

RESULTS

From a total of 36 pieces of guidance, 20 (56%) were eligible and 17 (47%) were included in our analysis. We identified 53 unique design labels, of which 19 (36%) were specific to diagnostic test accuracy designs. These referred to a total of 12 study design features. Labels were used in assigning different weights to studies in seven of the reports (41%) but never in the guidance documents.

CONCLUSION

Our study confirms a lack of clarity and standardization of test accuracy study design terms. There seems to be scope to reduce and harmonize the number of terms and still capture the design features that were deemed influential by those compiling the evidence reports. This should help decision makers in quickly identifying subgroups of included studies that should be weighted differently because their designs are more susceptible to bias.

Peritoneal Carcinomatosis Targeting with Tumor Homing Peptides

Over recent decades multiple therapeutic approaches have been explored for improved management of peritoneally disseminated malignancies—a grim condition known as peritoneal carcinomatosis (PC). Intraperitoneal (IP) administration can be used to achieve elevated local concentration and extended half-life of the drugs in the peritoneal cavity to improve their anticancer efficacy. However, IP-administered chemotherapeutics have a short residence time in the IP space, and are not tumor selective. An increasing body of work suggests that functionalization of drugs and nanoparticles with targeting peptides increases their peritoneal retention and provides a robust and specific tumor binding and penetration that translates into improved therapeutic response. Here we review the progress in affinity targeting of intraperitoneal anticancer compounds, imaging agents and nanoparticles with tumor-homing peptides. We review classes of tumor-homing peptides relevant for PC targeting, payloads for peptide-guided precision delivery, applications for targeted compounds, and the effects of nanoformulation of drugs and imaging agents on affinity-based tumor delivery.

An epidemiological investigation of an idiopathic myopathy in hunting dogs in New Zealand

AIM

To conduct an epidemiological investigation of an idiopathic myopathy, known as "Go Slow" (GSM), which was initially recognised in dogs used for pig hunting. A secondary aim was to describe the hunting activities, diet and health of dogs used for pig hunting in New Zealand.

METHODS

A retrospective cohort study was conducted between June 2014-June 2017. Cases of GSM in dogs were diagnosed by veterinarians using a combination of clinical history, physical examination findings, serum biochemistry and/or skeletal muscle histology. A telephone interview was conducted with the owner or primary veterinarian to provide information regarding the dog's diet and exercise over the 7 days preceding the onset of clinical signs. In August 2015, a separate online survey of owners of dogs used for pig hunting was conducted to characterise the normal hunting activities, diet and health of these dogs.

RESULTS

A total of 86 cases of GSM were recruited, of which 58 (67%) were pig hunting dogs, 16 (19%) pet dogs and 12 (14%) working farm dogs. Cases were most commonly reported in the upper North Island, and 65 (76 (95% CI=67-85)%) were from the Northland region. Processed commercial dog food had been fed to 93 (95% CI=88-98)% of affected dogs. Ingestion of raw, frozen or cooked wild pig in the preceding week was reported for 76 (88 (95% CI=82-95)%) dogs with the myopathy. In the survey of owners of healthy pig hunting dogs, 203 eligible responses were received; pig hunting was reported to most commonly occur in Northland (20.2%), Waikato (22.3%) and Bay of Plenty (23.2%) regions. Commercial dog food was fed to 172 (85 (95% CI=80-90)%) of the dogs included in this survey, and 55 (27 (95% CI=20-33)%) had eaten wild pig in the preceding week. The most common reported health problem in pig hunting dogs was traumatic wounds.

CONCLUSIONS

Cases of GSM were most commonly recognised in dogs used for pig hunting, but also occurred in pet and working farm dogs. The disease was most frequently reported in the upper North Island of New Zealand and ingestion of wild pig was a consistent feature in cases of this myopathy.

CLINICAL RELEVANCE

To minimise the risk of dogs developing this myopathy, it would seem prudent to avoid feeding any tissues from wild pigs to dogs in areas where the disease is known to occur.

Plasma NT-proBNP and Cell-Free DNA Concentrations after Prolonged Strenuous Exercise in Working Farm Dogs

BACKGROUND

Plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration is increased in dogs with myocardial dysfunction, and cell-free DNA (cfDNA) increases in numerous disease states. In humans, both of these biomarkers can be altered after endurance exercise.

OBJECTIVE

To investigate the effect of prolonged strenuous exercise on circulating NT-proBNP and cfDNA concentrations in working farm dogs.

ANIMALS

Six healthy, privately owned working farm dogs (4 Huntaways and 2 heading dogs) from the same hill country farm in New Zealand.

METHODS

Prospective, nonrandomised cohort study. Venous blood samples were collected before and after the dogs worked over 4 days. Plasma NT-proBNP concentrations were measured by a commercially available ELISA assay and cfDNA concentrations were determined by fluorometry without prior DNA extraction.

RESULTS

The baseline (before work, Day 1) median plasma NT-proBNP concentration was 664 pmol/L. A linear mixed-effects model showed that work increased plasma NT-proBNP concentrations by 101 ± 9% (P < 0.001), but with each consecutive day of work, NT-proBNP concentrations declined by 16 ± 4% (P < 0.001). The baseline median plasma cfDNA concentration was 653 ng/mL, and plasma cfDNA concentrations increased by 138 ± 45 ng/mL after work (P = 0.004).

CONCLUSIONS AND CLINICAL IMPORTANCE

The plasma concentration of NT-proBNP in healthy Huntaways and heading dogs after work can exceed the upper limit of the reference range. Results in dogs sampled on the day of prolonged strenuous exercise should be interpreted with caution. Plasma concentrations of cfDNA also increase with exercise, but further studies are needed to establish reference ranges in healthy dogs.

Targeting of p32 in peritoneal carcinomatosis with intraperitoneal linTT1 peptide-guided pro-apoptotic nanoparticles

Gastrointestinal and gynecological malignancies disseminate in the peritoneal cavity - a condition known as peritoneal carcinomatosis (PC). Intraperitoneal (IP) administration can be used to improve therapeutic index of anticancer drugs used for PC treatment. Activity of IP anticancer drugs can be further potentiated by encapsulation in nanocarriers and/or affinity targeting with tumor-specific affinity ligands, such as tumor homing peptides. Here we evaluated a novel tumor penetrating peptide, linTT1 (AKRGARSTA), as a PC targeting ligand for nanoparticles. We first demonstrated that the primary homing receptor for linTT1, p32 (or gC1qR), is expressed on the cell surface of peritoneal carcinoma cell lines of gastric (MKN-45P), ovarian (SKOV-3), and colon (CT-26) origin, and that peritoneal tumors in mice and clinical peritoneal carcinoma explants express p32 protein accessible from the IP space. Iron oxide nanoworms (NWs) functionalized with the linTT1 peptide were taken up and routed to mitochondria in cultured PC cells. NWs functionalized with linTT1 peptide in tandem with a pro-apoptotic [D(KLAKLAK)2] peptide showed p32-dependent cytotoxicity in MKN-45P, SKOV-3, and CT-26 cells. Upon IP administration in mice bearing MKN-45P, SKOV-3, and CT-26 tumors, linTT1-functionalized NWs showed robust homing and penetration into malignant lesions, whereas only a background accumulation was seen in control tissues. In tumors, the linTT1-NW accumulation was seen predominantly in CD31-positive blood vessels, in LYVE-1-positive lymphatic structures, and in CD11b-positive tumor macrophages. Experimental therapy of mice bearing peritoneal MKN-45P xenografts and CT-26 syngeneic tumors with IP linTT1-D(KLAKLAK)2-NWs resulted in significant reduction of weight of peritoneal tumors and significant decrease in the number of metastatic tumor nodules, whereas treatment with untargeted D(KLAKLAK)2-NWs had no effect. Our data show that targeting of p32 with linTT1 tumor-penetrating peptide improves tumor selectivity and antitumor efficacy of IP pro-apoptotic NWs. P32-directed intraperitoneal targeting of other anticancer agents and nanoparticles using peptides and other affinity ligands may represent a general strategy to increase their therapeutic index.

Hyaluronan-binding peptide for targeting peritoneal carcinomatosis

Peritoneal carcinomatosis results from dissemination of solid tumors in the peritoneal cavity, and is a common site of metastasis in patients with carcinomas of gastrointestinal or gynecological origin. Peritoneal carcinomatosis treatment is challenging as poorly vascularized, disseminated peritoneal micro-tumors are shielded from systemic anticancer drugs and drive tumor regrowth. Here, we describe the identification and validation of a tumor homing peptide CKRDLSRRC (IP3), which upon intraperitoneal administration delivers payloads to peritoneal metastases. IP3 peptide was identified by in vivo phage display on a mouse model of peritoneal carcinomatosis of gastric origin (MKN-45P), using high-throughput sequencing of the peptide-encoding region of phage genome as a readout. The IP3 peptide contains a hyaluronan-binding motif, and fluorescein-labeled IP3 peptide bound to immobilized hyaluronan in vitro. After intraperitoneal administration in mice bearing peritoneal metastases of gastric and colon origin, IP3 peptide homed robustly to macrophage-rich regions in peritoneal tumors, including poorly vascularized micro-tumors. Finally, we show that IP3 functionalization conferred silver nanoparticles the ability to home to peritoneal tumors of gastric and colonic origin, suggesting that it could facilitate targeted delivery of nanoscale payloads to peritoneal tumors. Collectively, our study suggests that the IP3 peptide has potential applications for targeting drugs, nanoparticles, and imaging agents to peritoneal tumors.

In Vivo Molecular MRI of ICAM-1 Expression on Endothelium and Leukocytes from Subacute to Chronic Stages After Experimental Stroke

Molecular MRI allows in vivo detection of vascular cell adhesion molecules expressed on inflamed endothelium, which enables detection of specific targets for anti-neuroinflammatory treatment. We explored to what extent MR contrast agent targeted to intercellular adhesion molecule-1 (ICAM-1) could detect endothelial- and leukocyte-associated ICAM-1 expression at different stages after experimental stroke. Furthermore, we assessed potential interfering effects of ICAM-1-targeted contrast agent on post-stroke lesion growth. Micron-sized particles of iron oxide (MPIO) functionalized with control IgG (IgG-MPIO) or anti-ICAM-1 antibody (αICAM-1-MPIO) were administrated at 1, 2, 3, 7, and 21 days after unilateral transient middle cerebral artery occlusion in mice, followed by in vivo MRI and postmortem immunohistochemistry. αICAM-1-MPIO induced significant contrast effects in the lesion core on post-stroke days 1, 2, and 3, and in the lesion borderzone and contralesional tissue on post-stroke day 2. αICAM-1-MPIO were confined to ICAM-1-positive vessels and occasionally co-localized with leukocytes. On post-stroke day 21, abundant leukocyte-associated αICAM-1-MPIO was immunohistochemically detected in the lesion core. However, MRI-based detection of αICAM-1-MPIO-labeled leukocytes was confounded by pre-contrast MRI hypointensities, presumably caused by phagocytosed blood remains. IgG-MPIO did not induce significant MRI contrast effects at 1 h after injection. Lesion development was not affected by injection of αICAM-1-MPIO or IgG-MPIO. αICAM-1-MPIO are suitable for in vivo MRI of ICAM-1 expression on vascular endothelium and leukocytes at different stages after stroke. Development of clinically applicable MPIO may offer unique opportunities for MRI-based diagnosis of neuroinflammation and identification of anti-inflammatory targets in acute stroke patients.

A novel oral iron-complex formulation: Encapsulation of hemin in polymeric micelles and its in vitro absorption

Anemia resulting from iron deficiency is one of the most prevalent diseases in the world. As iron has important roles in several biological processes such as oxygen transport, DNA synthesis and cell growth, there is a high need for iron therapies that result in high iron bioavailability with minimal toxic effects to treat patients suffering from anemia. This study aims to develop a novel oral iron-complex formulation based on hemin-loaded polymeric micelles composed of the biodegradable and thermosensitive polymer methoxy-poly(ethylene glycol)-b-poly[N-(2-hydroxypropyl)methacrylamide-dilactate], abbreviated as mPEG-b-p(HPMAm-Lac₂). Hemin-loaded micelles were prepared by addition of hemin dissolved in DMSO:DMF (1:9, one volume) to an aqueous polymer solution (nine volumes) of mPEG-b-p(HPMAm-Lac₂) followed by rapidly heating the mixture at 50°C to form hemin-loaded micelles that remain intact at room and physiological temperature. The highest loading capacity for hemin in mPEG-b-p(HPMAm-Lac₂) micelles was 3.9%. The average particle diameter of the hemin-micelles ranged from 75 to 140nm, depending on the concentration of hemin solution that was used to prepare the micelles. The hemin-loaded micelles were stable at pH 2 for at least 3 h which covers the residence time of the formulation in the stomach after oral administration and up to 17 h at pH 7.4 which is sufficient time for uptake of the micelles by the enterocytes. Importantly, incubation of Caco-2 cells with hemin-micelles for 24 h at 37°C resulted in ferritin levels of 2500ng/mg protein which is about 10-fold higher than levels observed in cells incubated with iron sulfate under the same conditions. The hemin formulation also demonstrated superior cell viability compared to iron sulfate with and without ascorbic acid. The study presented here demonstrates the development of a promising novel iron complex for oral delivery.

First report and histological features of Chlamydia pecorum encephalitis in calves in New Zealand

CASE HISTORY

Between September and October 2013, 40 of 150 crossbred Friesian dairy calves on a farm in the Manawatu region of New Zealand developed neurological signs when between 1 and 3 months of age. Calves were grazed in multiple mobs and calves from each mob were affected. A variable response was observed to initial treatment with thiamine, fluoroquinolone antibiotics and non-steroidal anti-inflammatory drugs.

CLINICAL AND PATHOLOGICAL FINDINGS

Affected calves exhibited a range of neurological signs that included generalised depression, hind limb ataxia with a stiff gait, and knuckling of the fetlocks. In advanced cases, calves became recumbent with opisthotonous. Over a 4-week period, 13 calves died or were subject to euthanasia and a thorough necropsy was performed on three of these calves. Necropsy findings included fibrinous peritonitis, pleuritis and pericarditis, with no gross abnormalities visible in the brain or joints. Histology of the brain was possible in seven of the affected calves, with lesions ranging from lymphocytic and histiocytic vasculitis and meningoencephalitis, to extensive thrombosis and neutrophilic inflammation. Immunohistochemistry using an anti-chlamydial lipopolysaccharide antibody revealed positive immuno-staining in all seven cases, with no brain samples exhibiting immunostaining for Histophilus somni. DNA was extracted from a sample of fresh brain from one case and chlamydial DNA sequences were amplified by PCR and found to be identical to Chlamydia pecorum. PCR was also performed on formalin-fixed brain tissue from three of the other cases, but no chlamydial DNA was amplified.

DIAGNOSIS

Chlamydia pecorum meningoencephalomyelitis (sporadic bovine encephalomyelitis).

CLINICAL RELEVANCE

This is the first time that C. pecorum has been confirmed as a cause of clinical disease in New Zealand. Practitioners should be aware of this disease as a differential in calves with neurological signs, and submit samples of formalin-fixed brain as well as fresh brain to enable confirmation of suspected cases using PCR analysis. Furthermore, these cases illustrate that the histological lesions in the brains of calves with C. pecorum are more variable than previously reported, and pathologists should be aware that histological features may overlap with those traditionally ascribed to other organisms, such as H. somni.

iRGD peptide conjugation potentiates intraperitoneal tumor delivery of paclitaxel with polymersomes

Polymersomes are versatile nanoscale vesicles that can be used for cytoplasmic delivery of payloads. Recently, we demonstrated that pH-sensitive polymersomes exhibit an intrinsic selectivity towards intraperitoneal tumor lesions. A tumor homing peptide, iRGD, harbors a cryptic C-end Rule (CendR) motif that is responsible for neuropilin-1 (NRP-1) binding and for triggering extravasation and tumor penetration of the peptide. iRGD functionalization increases tumor selectivity and therapeutic efficacy of systemic drug-loaded nanoparticles in many tumor models. Here we studied whether intraperitoneally administered paclitaxel-loaded iRGD-polymersomes show improved efficacy in the treatment of peritoneal carcinomatosis. First, we demonstrated that the pH-sensitive polymersomes functionalized with RPARPAR (a prototypic CendR peptide) or iRGD internalize in the cells that express NRP-1, and that internalized polymersomes release their cargo inside the cytosol. CendR-targeted polymersomes loaded with paclitaxel were more cytotoxic on NRP-1-positive cells than on NRP-1-negative cells. In mice bearing peritoneal tumors of gastric (MKN-45P) or colon (CT26) origin, intraperitoneally administered RPARPAR and iRGD-polymersomes showed higher tumor-selective accumulation and penetration than untargeted polymersomes. Finally, iRGD-polymersomes loaded with paclitaxel showed improved efficacy in peritoneal tumor growth inhibition and in suppression of local dissemination compared to the pristine paclitaxel-polymersomes or Abraxane. Our study demonstrates that iRGD-functionalization improves efficacy of paclitaxel-polymersomes for intraperitoneal treatment of peritoneal carcinomatosis.

Abstract 2164: Tenascin-C binding peptides for cancer targeting

Extracellular matrix protein tenascin C (TNC) is strongly overexpressed in the stroma of many solid tumors. TNC expression is upregulated at the invasive front of tumors while being nearly undetectable in normal adult tissues. TNC-targeted humanized antibodies are undergoing clinical development for targeting compounds to solid tumors. Compared to antibodies, homing peptides may have more favorable extravasation and tumor penetration properties.

We used in vitro T7 peptide display to identify peptides that bind to the alternatively spliced domain C of the large isoform of Tenascin-C (TNC FnIIIC). The selected phage pool showed 500-fold increase in binding to immobilized TNC FnIIIC. Candidate TNC FnIIIC-binding peptides (designated PL1- 3) were found to bind to TNC FnIII C protein, to the extracellular matrix extracted from PC3 prostate tumors and to cultured tumor cells known to overexpress TNC. To evaluate candidate peptides in vivo, we used mice bearing patient-derived xenografts of P3 glioma (R. Bjerkvig, Bergen, Norway), 4T1 breast tumors, and PC-3prostate carcinoma. A pool of the phages displaying TNC FnIIIC binding peptides, and a panel of phages displaying published tumor homing and control peptides was injected intravenously in tumor-bearing mice, and relative tumor homing and background in control tissues was determined for each phage using high-throughput sequencing (HTS) of phage genomic DNA. These studies demonstrated that among TNC FnIIIC targeting peptides, the PL3 peptide showed the best tumor homing and specificity profile. To evaluate the potential of the synthetic PL3 peptide for tumor targeting of nanoparticles, we coupled PL3 peptide to iron oxide nanoworms (IONW) - paramagnetic nanoparticles that are PEGylated to extend blood half-life, and have because of their elongated shape more effective targeting properties than spherical nanoparticles. 5 hours after intravenous administration of 7.5mg/kg of IONW in mice bearing PC3 prostate cancer xenografts, PL3-IONW but not control IONW showed a robust accumulation in tumor vasculature, and some extravasation into extravascular tumor tissue. Our data suggests that the newly identified TNC FnIIIC targeting peptide, PL3, may be used for payload delivery into tumor stroma. Currently, we are evaluating PL3-targeted IONWs as a MRI contrast agent and as carriers for cytotoxic compounds to TNC expressing tumors.

Citation Format: Prakash Lingasamy, Allan Tobi, Hedi Hunt, Pille Säälik, Markko Salumäe, Tambet Teesalu, Tambet Teesalu. Tenascin-C binding peptides for cancer targeting. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2164.

Abstract 1343: P32-targeting TT1 peptide delivers nanoparticles to intracranial glioblastomas

Targeted delivery of cancer therapeutics using affinity ligands can dramatically improve antitumor efficacy. Over the years a number of homing peptides that upon systemic injection accumulate in solid tumors have been identified by in vivo peptide phage display. In a quest to find homing peptides optimally suited for drug delivery to high-grade gliomas, our laboratories are using advanced mouse models of glioblastoma (GBM) to systematically audit known tumor-homing peptides and to perform new in vivo screens using peptide phage libraries.

P32 is a mitochondrial chaperone that is aberrantly expressed on the cell surface in activated malignant and stromal cells in tumors. P32 is a receptor for widely used LypP-1 peptide and for recently identified TT1 peptide. Here we show that iron oxide nanoworms (IONW) functionalized with linear TT1 peptide (CKRGARST) strongly home to intracranial GBMs grafted in immune deficient mice. IONW are paramagnetic nanoparticles that are PEGylated to extend blood half-life, and have, because of their elongated shape, more effective targeting properties than spherical nanoparticles. Five hours after intravenous injection of IONW (7.5 mg/kg), macroscopic fluorescence imaging demonstrated robust homing of TT1-IONW in GBMs of murine origin (WT GBM and VEGF KO GBM from the G. Berger lab) and in a patient-derived glioma model (P13 model from the Bjerkvig lab). Confocal microscopy confirmed the presence of TT1 but not control IONW in gliomas, with TT1-IONW signal showing partial overlap with blood- and lymphatic vessel markers (CD31 and LYVE-1) in WT GBM and P13 gliomas, whereas lower level of colocalization with these markers was detected for mouse GBM not expressing VEGF. In addition, moderate colocalization between TT1-IONW and the macrophage marker CD11b was detected in the P13 tumors. Detailed phenotyping and functional characterization of TT1-positive macrophages is ongoing.

Our data suggest that TT1 peptide has potential applications as a glioma-targeting vehicle. Currently, we are evaluating TT1-targeted IONWs as a contrast agent for glioma MRI and as carriers for cytotoxic compounds.

Citation Format: Pille Säälik, Hedi Hunt, Allan Tobi, Anne-Mari Anton Willmore, Kadri Toome, Shweta Sharma, Ramana Kotamraju, Gabriele Bergers, Rolf Bjerkvig, Erkki Ruoslahti, Tambet Teesalu, Tambet Teesalu. P32-targeting TT1 peptide delivers nanoparticles to intracranial glioblastomas. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1343.

Use of the Atlantic nut clam (Nucula proxima) and catworm (Nephtys incisa) in a sentinel species approach for monitoring the health of Bay of Fundy estuaries

Designing an effective environmental monitoring system for population responses requires knowledge of the biology of appropriate sentinel species and baseline information on the area's physical and chemical characteristics. This study collected information in Saint John Harbor, NB, Canada, for two abundant marine benthic invertebrates, the Atlantic nut clam (Nucula proxima) and the catworm (Nephtys incisa) to characterize their seasonal and spatial variability, determine the ideal sampling time and methods, and develop baseline data for future studies. We also evaluated whether contamination is impacting invertebrates by comparing sediment metal concentrations to responses of benthic infauna. Metals were generally below sediment quality guidelines except for nickel and arsenic. Clam densities were variable between sites but not seasons, whereas catworm densities were not significantly different between sites or seasons. Overall, these species show potential for environmental monitoring, although investigation at more contaminated sites is warranted to assess their sensitivity.

Abstract PD3-02: Second-generation selective glucocorticoid receptor modulators in triple-negative breast cancer

Triple-negative breast cancer (TNBC) lacks expression of the estrogen receptor (ER), progesterone receptor (PR), and HER2. A subset of primary TNBCs (at least 30%) expresses moderate to strong glucocorticoid receptor (GR) in greater than 10% of invasive tumor cells; in addition, we have reported that increased GR signaling promotes TNBC cell survival. Furthermore, our laboratory recently observed that patients with early stage/high-GR-expressing TNBCs have a relatively poor prognosis. Therefore, GR is being explored as a target for improving outcome in TNBC. Indeed, mifepristone, a well-characterized non-selective steroidal GR/PR antagonist, has shown promise in reversing GR-mediated tumor cell-survival signaling in TNBC. In vivo, increased TNBC xenograft chemosensitivity was observed when mifepristone was added to chemotherapy treatment. Most recently, a Phase I clinical trial demonstrated the safety and potential efficacy of mifepristone added to nab-paclitaxel chemotherapy in Stage IV TNBC patients.

Three highly selective non-steroidal GR antagonists (GRAs) have been investigated, CORT108297. CORT125134 (two aryl pyrazole-fused azadecalins) and CORT118335 (a pyrimidine dione). These new GRAs have 1) far less cross-reactivity than mifepristone with other nuclear receptor family members and 2) lower interaction profiles for drug metabolizing CYP enzymes. We hypothesized that selective GRAs would not only inhibit GR-induced pro-survival gene expression, but also increase TNBC chemosensitivity, and may eventually be a valuable adjunct therapy for treating chemotherapy-resistant TNBC.

To understand how GR modulators interact with the GR ligand-binding domain (LBD), we are employing two approaches: 1) computational modeling of the GRA-GR LBD based on published crystal structures of the GR LBD with mifepristone (in collaboration with UIUC), and 2) crystal structure analysis of the GR LBD with GR modulators. Preliminary computational results indicate that CORT108297 docks into the LBD and antagonizes GR activity by indirectly disordering Helix 12. Experiments are ongoing using various buffer conditions to produce crystals of the GR LBD with CORT108297 and CORT118335 for x-ray crystallography.

Secondly, we are functionally characterizing CORT108297, CORT125134, and CORT118335 for their ability to inhibit glucocorticoid induction of key GR-mediated target genes. Over the course of eight hours, we observed that the compounds exhibited temporal antagonism of the expression of GR target genes encoding anti-apoptotic proteins such as SGK-1, MCL-1, and MKP-1/DUSP1. Lastly, we are examining the selective GRAs' ability to enhance tumor cell cytotoxicity from paclitaxel in cell culture and in TNBC xenograft models. Preliminary results indicate that CORT125134 and CORT108297 significantly increase GR+ TNBC sensitivity to paclitaxel, and are well-tolerated in our in vivo models.

Citation Format: West DC, Hosfield DJ, Mayne CG, Skor MN, Styke SC, Pierce CF, Kocherginsky M, Hunt H, Fleming GF, Szmulewitz RZ, Tajkhorshid E, Greene GL, Conzen SD. Second-generation selective glucocorticoid receptor modulators in triple-negative breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD3-02.

Paclitaxel-Loaded Polymersomes for Enhanced Intraperitoneal Chemotherapy

Peritoneal carcinomatosis is present in more than 60% of gastric cancer, 40% of ovarian cancer, and 35% of colon cancer patients. It is the second most common cause of cancer-related mortality, with a median survival of 1 to 3 months. Cytoreductive surgery combined with intraperitoneal chemotherapy is the current clinical treatment, but achieving curative drug accumulation and penetration in peritoneal carcinomatosis lesions remains an unresolved challenge. Here, we used flexible and pH-sensitive polymersomes for payload delivery to peritoneal gastric (MKN-45P) and colon (CT26) carcinoma in mice. Polymersomes were loaded with paclitaxel and in vitro drug release was studied as a function of pH and time. Paclitaxel-loaded polymersomes remained stable in aqueous solution at neutral pH for up to 4 months. In cell viability assay on cultured cancer cell lines (MKN-45P, SKOV3, CT26), paclitaxel-loaded polymersomes were more toxic than free drug or albumin-bound paclitaxel (Abraxane). Intraperitoneally administered fluorescent polymersomes accumulated in malignant lesions, and immunofluorescence revealed an intense signal inside tumors with no detectable signal in control organs. A dual targeting of tumors was observed: direct (circulation-independent) penetration, and systemic, blood vessel-associated accumulation. Finally, we evaluated preclinical antitumor efficacy of paclitaxel-polymersomes in the treatment of MKN-45P disseminated gastric carcinoma using a total dose of 7 mg/kg. Experimental therapy with paclitaxel-polymersomes improved the therapeutic index of drug over free paclitaxel and Abraxane, as evaluated by intraperitoneal tumor burden and number of metastatic nodules. Our findings underline the potential utility of the polymersome platform for delivery of drugs and imaging agents to peritoneal carcinomatosis lesions. Mol Cancer Ther; 15(4); 670-9. ©2016 AACR.

A novel combined glucocorticoid-mineralocorticoid receptor selective modulator markedly prevents weight gain and fat mass expansion in mice fed a high-fat diet

BACKGROUND

We have previously shown that antagonism of the mineralocorticoid receptor (MR) results in a potent antiadipogenic activity, in vitro and in vivo. Excessive glucocorticoid exposure is associated with obesity and related disorders in humans and mice.

METHODS

In this study, responses to a novel combined glucocorticoid receptor (GR)/MR antagonist were investigated in a model of diet-induced obesity. Female 10-week-old C57BL/6J mice were fed with normal chow or a high-fat diet (HFD) for 9 weeks. Mice fed a HFD were concomitantly treated for 9 weeks with the GR antagonist mifepristone (80 mg kg(-1) per day) or the novel combined GR/MR antagonist CORT118335 (80 mg kg(-1) per day). Male, juvenile 6-week-old C57BL/6J mice fed HFD were treated with CORT118335 for 4 weeks.

RESULTS

Mice fed a HFD showed a significant increase in total body weight and white fat mass, with impaired glucose tolerance and increased fat infiltration in livers. Interestingly, only CORT118335 completely prevented the HFD-induced weight gain and white fat deposition, whereas mifepristone showed no effect on body weight and modestly increased subcutaneous fat mass. Importantly, food intake was not affected by either treatment, and CORT118335 dramatically increased PGC-1α protein expression in adipose tissue, without any effect on UCP1. Both CORT118335 and mifepristone produced metabolic benefit, improving glucose tolerance, increasing adiponectin plasma levels, decreasing leptin and reducing mean adipocyte size. When tested in vitro, CORT118335 markedly reduced 3T3-L1 differentiation and reversed MR-mediated pro-adipogenic effects of aldosterone; differently, GR-mediated effects of dexamethasone were not antagonized by CORT118335, suggesting that it mostly acts as an antagonist of MR in cultured preadipocytes.

CONCLUSIONS

Combined GR/MR pharmacological antagonism markedly reduced HFD-driven weight gain and fat mass expansion in mice through the increase in adipose PGC-1α, suggesting that both receptors represent strategic therapeutic targets to fight obesity. The effects of CORT118335 in adipocytes seem predominantly mediated by MR antagonism.

Distinct neuropsychological profiles correspond to distribution of cortical thinning in inherited prion disease caused by insertional mutation

BACKGROUND

The human prion diseases are a group of universally fatal neurodegenerative disorders associated with the auto-catalytic misfolding of the normal cell surface prion protein (PrP). Mutations causative of inherited human prion disease (IPD) include an insertion of six additional octapeptide repeats (6-OPRI) and a missense mutation (P102L) with large families segregating for each mutation residing in southern England. Here we report for the first time the neuropsychological and clinical assessments in these two groups.

METHOD

The cognitive profiles addressing all major domains were obtained for 26 patients (18 6-OPRI, 8 P102L) and the cortical thickness determined using 1.5T MRI in a subset of 10 (six 6-OPRI, four P102L).

RESULTS

The cognitive profiles were different in patients with the two mutations in the symptomatic phase of the disease. The 6-OPRI group had lower premorbid optimal levels of functioning (assessed on the NART) than the P102L group. In the symptomatic phase of the disease the 6-OPRI patients had significantly more executive dysfunction than the P102L group and were more impaired on tests of perception and nominal functions. There was anecdotal evidence of low premorbid social performance in the 6-OPRI but not P102L patients. Cortical thinning distribution correlated with the neuropsychological profile in the 6-OPRI group principally involving the parietal, occipital and posterior frontal regions. The small number of patients in the P102L group precluded statistical comparison between the groups.

CONCLUSIONS

The 6-OPRI patients had more widespread and severe cognitive dysfunction than the P102L group and this correlated with cortical thinning distribution.

A preliminary characterisation of cognition and social cognition in spinocerebellar ataxia types 2, 1, and 7

Over the last decade, studies have implicated the cerebellum not only in motor functioning, but also in cognition and social cognition. Although some aspects of cognition have been explored in the five most common forms of Spinocerebellar Ataxia (SCA), social cognition in these patients has rarely been examined. The present study provides a preliminary characterisation of the severity of cognitive and social cognitive impairments in patients with SCA2, SCA1 and SCA7 using an identical battery to the one previously used in SCA3 and SCA6 patients for comparison. The cognitive profiles of SCA1 and SCA7 patients were comparable to that of SCA6 patients; SCA1 patients had relatively intact profiles, while SCA7 patients demonstrated only some selective deficits. In contrast, SCA2 patients showed the greatest impairments, similarly to SCA3 patients. On tests of social cognition, SCA2 and SCA7 patients were impaired on a task of emotion attribution, whereas one SCA1 patient had a Theory of Mind deficit, which has also been documented in SCA3 and SCA6. We provide preliminary evidence that the neuropsychological profiles of SCA patients correspond well with the severity of pathological and clinical features. Moreover, these patients may also have social cognition impairments. Overall, we suggest that there is a degree of heterogeneity in the types of cognitive and social cognitive impairments in SCA patients.

Erratum: Preliminary Characterisation of Cognition and Social Cognition in Spinocerebellar Ataxia Types 2, 1, and 7

[This corrects the article DOI: 10.3233/BEN-2010-0270.].

Evaluation of copper sulphate, formalin and peracetic acid in footbaths for the treatment of digital dermatitis in cattle

The efficacy of three non-antibiotic products (copper sulphate, formalin and peracetic acid) was compared with the efficacy of erythromycin, when the four substances were applied in footbaths for the treatment of cows with digital dermatitis. The cows were divided into four groups on the basis of their current housing and randomly allocated to one of the four treatments. Cattle allocated to the non-antibiotic treatments were footbathed daily for seven days, but the cattle treated with erythromycin were footbathed for two days only. Complete records were obtained for 252 lesions from 169 cows. There were significant reductions in the lesion scores of all four groups, but there was no significant effect of treatment and no significant interaction between treatment and time.

Development and characterization of monoclonal antibodies to subgroup J avian leukosis virus

In an attempt to develop a specific diagnostic test for avian leukosis virus (ALV) subgroup J (ALV-J) strain Hc1, four monoclonal antibodies (MAbs), JE9, G2, 145, and J47, were generated that are specific for ALV-J envelope glycoprotein, gp85. Polymerase chain reaction (PCR) was used to amplify genomic pro-viral DNA of Avian Disease and Oncology Laboratory (ADOL)-Hc1 and ADOL-4817 envelope genes. Both open reading frames encoding glycoproteins gp85 and gp37 were cloned into baculoviruses. Abundant expression of gp85 and gp37 was detected in the recombinant viruses with specific antibody to Hc1 strain of the ALV-J. The expressed proteins were used for immunization of mice to produce hybridoma cell lines secreting MAbs specific to ALV-J envelope protein. A panel of MAbs was generated by fusing NS1 myeloma cells and spleen cells from mice immunized with the recombinant baculoviruses. With the use of an immunofluorescence assay, three MAbs (JE9, G2, 145) reacted with ALV-J but not with subgroups A, B, C, D, or E of ALV. MAb J47 reacted with all exogenous subgroups of ALV including A, B, C, D, and J but not with endogenous subgroup E viruses. Western blot analysis was performed with all four MAbs against recombinant baculovirus and Hc1-infected chicken embryo fibroblast (CEF) lysates. A major band with a molecular weight about 90 kD corresponding to the size of ALV-J envelope was consistently obtained. With these MAbs, we detected the Hc1 antigen in CEFs infected with several ALV-J viruses isolated in the United States and also in tissue sections from chickens infected with Hc1 strain of ALV-J. These MAbs will be useful reagents for the diagnosis of ALV-J infection because they recognize a common antigenic epitope in six isolates tested thus far.

Identification and characterization of recombinant subgroup J avian leukosis viruses (ALV) expressing subgroup A ALV envelope

Three recombinant avian leukosis subgroup J viruses, ADOL 5701A, ADOL 5701ADelta, and ADOL 6803A, carrying a subgroup A envelope have been isolated and characterized. These viruses were identified by their ability to replicate in DF-1/J, a recombinant chicken embryo fibroblast (CEF) cell line expressing the subgroup J envelope that is resistant to subgroup J replication. Flow cytometric analysis of DF-1/J cells infected with ADOL 5701 and ADOL 6803, two subgroup J isolates, indicated cross-reactivity with subgroup A chicken polyclonal serum. Based on published sequences of subgroups A and J isolates, we designed a series of primers to PCR amplify the envelope and LTR of these viruses. PCR products were obtained when the forward primer was specific for subgroup A gp85 envelope protein gene and the reverse primer was specific for subgroup J LTR. Sequence analysis of the PCR products indicated that these viruses had a subgroup A gp85, a subgroup E gp37, and a subgroup J LTR. Interestingly, these viruses had previously been propagated in CEF from the alv6 chicken line, a line that carries a replication defective recombinant endogenous virus expressing a subgroup A envelope (RAV 0-A(1)). Sequence analysis of RAV 0-A(1) gp85 and gp37 envelope proteins indicated that they were almost identical to those of the recombinants ADOL 5701A and ADOL 6803A. These results indicate that these three recombinant viruses arose by recombination between exogenous subgroup J isolates and a recombinant defective endogenous virus with subgroup A envelope.

Glucocorticoid receptor down-regulation in neutrophils of periparturient cows

OBJECTIVE

To determine effects of parturition on glucocorticoid receptor (GR) expression in neutrophils, serum cortisol concentration, and total blood leukocyte and neutrophil counts in periparturient dairy cows.

ANIMALS

23 Holstein cows.

PROCEDURE

Blood samples were collected from 8 multiparous and 5 primiparous periparturient cows at various times from 28 days before parturition until 14 days after parturition. Glucocorticoid receptor expression in neutrophils, serum cortisol concentration, and total blood leukocyte and neutrophil counts were determined. Results were compared with results from control samples obtained from 5 multiparous and 5 primiparous Holstein cows in midpregnancy.

RESULTS

Neutrophils from periparturient cows had 49% reduction in GR expression at calving, compared with GR expression 2 to 4 weeks before calving, and 39% reduction, compared with neutrophils from cows in midpregnancy. Reduction in neutrophil GR expression began 1 week before calving and was most severe at calving and 24 hours after calving; a significant difference in GR expression was detected between primiparous and multiparous cows. Serum cortisol concentrations and total leukocyte and neutrophil counts were significantly increased at calving and returned to baseline values by 24 hours after calving. Significant negative correlations were detected between neutrophil GR expression and serum cortisol concentration, total leukocyte count, and neutrophil count.

CONCLUSIONS AND CLINICAL RELEVANCE

Reduced GR expression in blood neutrophils of periparturient dairy cows was associated with increased serum cortisol concentrations, leukocytosis, and neutrophilia. Thus, GR down-regulation in neutrophils may be involved in periparturient neutrophil dysregulation and may cause increased susceptibility to mastitis.

Glucocorticoid receptor expression profiles in mononuclear leukocytes of periparturient Holstein cows

Cortisol-activated glucocorticoid receptors modulate cellular responses to stress by translocating from the cytosol to the nucleus and enhancing or repressing the transcription of target genes. The functional capacity of mononuclear leukocytes is inhibited in parturient dairy cows at a time when blood cortisol concentrations are high. Because the glucocorticoid receptor is autoregulatory in many cell types, the hypothesis of the current study was that glucocorticoid receptor expression by mononuclear leukocytes is altered around parturition in association with elevated blood cortisol. If true, the glucocorticoid receptor could be involved in suppressed functions of mononuclear leukocytes in parturient cows. The objectives of this study were to determine effects of parturition on lymphocyte and monocyte glucocorticoid receptor expression and to correlate expression with serum cortisol concentrations. Objectives were achieved by using fluorescence staining and flow cytometric analyses to monitor glucocorticoid receptors in peripheral blood mononuclear leukocytes collected multiple times from 13 periparturtient test cows (eight multi- and five primiparous) and 10 midgestation control cows (five multi- and five primiparous). Serum cortisol concentrations were determined by radioimmunoassay. Based on intensity of the fluorescent glucocorticoid receptor stain, parturition caused 42 and 47% reductions in lymphocyte and monocyte glucocorticoid receptor expression, respectively, compared with mean expression in corresponding cells from control cows. When mean prepartum values were compared with nadir values at parturition in the test cows, glucocorticoid receptor expression was reduced by 67% in lymphocytes and by 54% in monocytes. Mononuclear cell expression of glucocorticoid receptors was negatively correlated with serum cortisol concentrations. Results suggest that glucocorticoid receptors are down-regulated in bovine mononuclear leukocytes in association with increased adrenal secretion of cortisol at calving. It is possible that glucocorticoid receptor down-regulation is also associated with altered phenotype or function (or both) of lymphocytes and monocytes. This possibility should be substantiated because it could explain increased disease susceptibility in periparturient dairy cows.

Comparison of specialized and standard enteral formulas in trauma patients

STUDY OBJECTIVE

To compare selected nutrition and immunologic markers and infection in trauma patients receiving a specialized enteral formula with those receiving standard enteral therapy.

DESIGN

Prospective, randomized clinical trial.

SETTING

Level 1 trauma center at a county government hospital.

PATIENTS

Forty-one consecutive patients with major trauma who required enteral nutrition support. Thirty-seven patients completed the study. Four patients (two in each group) were excluded, as additional operative procedures prevented initiation of enteral feedings within 7 days of injury.

INTERVENTIONS

Nineteen patients fed the specialized enteral formula received supplemental arginine, linolenic acid, beta-carotene, and hydrolyzed protein for up to 10 days. Eighteen control patients received standard enteral nutrition.

MEASUREMENTS AND MAIN RESULTS

After study entry, patients who received the specialized enteral formula had fewer infections than those receiving standard enteral nutrition (3/19 vs 10/18; p < 0.05). The change in nitrogen balance was significantly better (p < 0.05) from day 1 (-11.8 +/- 1.8 g/day) to day 5 (-5.9 +/- 2.0 g/day) for the group who received the specialized formula compared with the group who received standard enteral nutrition (-7.3 +/- 1.7 g/day to -7.4 +/- 2.8 g/day). Similarly, the change in C-reactive protein serum concentration was significantly better (p < 0.05) from day 1 (18.0 +/- 2.1 mg/dl) to day 5 (11.8 +/- 1.5 mg/dl) in the group who received the specialized formula compared with the group who received standard enteral nutrition (17.6 +/- 1.2 mg/dl to 14.4 +/- 1.7 mg/dl). The CD4:CD8 ratio increased more in the group who received the specialized formula, although this difference did not reach statistical significance.

CONCLUSION

Trauma patients who received the specialized enteral formula demonstrated a decreased incidence of infection and increased improvements in nitrogen balance and other indexes of stress. Additional clinical trials demonstrating positive patient outcomes are necessary before these specialized enteral formulas are used as the standard of practice in critically ill patients.

Dreams of Freud and Jung: reciprocal relationships between social relations and archetypal/transpersonal imagination

Phenomenological and quantitative comparisons of the dreams of Freud and Jung become the basis for a more extended understanding of the relation between the psychodynamic and transpersonal/archetypal perspectives. Winnicott's distinction between the dimensions of being and doing/relating offers a developmental model of these perspectives based on a dialectic between two lines of growth-each with its own forms of health/pathology and its own primitive/advanced expressions. These dimensions, in both their positive and negative forms, are shown to be densely intertwined throughout the dreams (and characters) of Freud and Jung, whose theories emerge as reasonable reflections of their complementary ways of being in the world.

Static threshold variability in the peripheral visual field in normal subjects

We assessed the variability of point-wise static threshold values and the components of fluctuation outside the central 30 degrees field in 20 normal individuals tested on the Humphrey field analyzer. We found a mean short-term fluctuation of 2.37 dB, a long-term heterogeneous fluctuation of 5.28 dB, and a long-term homogeneous fluctuation of 1.10 dB. All components of fluctuation were greatest superiorly. Point-wise variation was highest superiorly and nasally and increased with greater eccentricity from fixation in all but the temporal quadrant. Also, point-wise variation was greater between individuals than between tests in a single individual. This study suggests that outside the central 30 degrees field, changes in individual threshold measurements in the superior and nasal quadrants should be greater than those in the temporal or inferior quadrants before they can be distinguished from normal variation.

A cognitive-psychological perspective on Gillespie's "Lights and lattices": some relations among perception, imagery, and thought

George Gillespie's valuable observations on light and lattice imageries are played in the context of current research and theory on cognitive imagery (Kosslyn, Pylyshyn), ordinary and lucid dreaming, representational geometric imagery in scientific thought, the author's previous writings on altered states of consciousness, and Gibson's views on perception and imagery. Gillespie's reports show categories of imagery deconstruction and abstraction that link these areas and suggest an integrative model of the varieties of symbolic imagery.

Influence of avian pancreatic polypeptide on pancreatic and biliary secretion in laying hens

White Leghorn hens, 14 to 29 wk of age, were surgically prepared with cannulae for collecting secretions from the cystic duct and the duct draining the ventral pancreatic lobe and for infusing the jugular vein with avian pancreatic polypeptide (aPP) or saline. A plasma infusion rate that produced a plasma level of 15 ng of aPP/mL was used. A comparison of values obtained during saline infusion with those obtained during aPP infusion indicated that pancreatic and biliary secretory volumes and pancreatic total protein concentration were significantly depressed by aPP. The pH of pancreatic and biliary secretions were not significantly affected by aPP. Because aPP also depresses gastric secretion and motility in hens, it is proposed that its physiological role may be to oppose or modulate the actions of other, stimulatory gastrointestinal hormones.

Reduction in myocardial acidosis using blood cardioplegia

The composition of the ideal cardioplegic solution is controversial. Blood cardioplegia is an attractive alternative to standard crystalloid solutions, though its superiority in preserving myocardial metabolism has not been demonstrated. Using a new pH electrode system, this study contrasts the effects of blood and crystalloid solutions upon the generation of myocardial acidosis during global ischemia. Thirty-eight mongrel dogs underwent a 120-min period of aortic cross clamping using systemic hypothermia. To maintain myocardial temperature below 15 degrees C, 19 dogs received multiple doses of a bicarbonate containing crystalloid cardioplegic solution (Group I), while 19 dogs received multiple doses of blood cardioplegia (Group II). Myocardial pH and temperature were continuously monitored in the subendocardial region of the left ventricle. There was no difference in baseline pH between Group I (7.13 +/- 0.05) and Group II (7.17 +/- 0.05, P:NS). With systemic cooling and the initial bolus of cardioplegia, myocardial pH rose to 7.42 +/- 0.04 in Group I and 7.42 +/- 0.06 in Group II (P:NS). After 120 min of global ischemia, myocardial pH decreased to 6.61 +/- 0.05 in Group I and 7.07 +/- 0.05 in Group II (P less than 0.001). Blood cardioplegia was most effective during the first hour of aortic cross clamp when myocardial pH rose by 0.13 +/- 0.04 pH units. In contrast, myocardial pH in Group I during the first hour of global ischemia fell -0.35 +/- 0.08 pH units (P less than 0.001 compared to Group II). During the second hour of cross clamp, myocardial pH declined both in Group I (0.26 +/- 0.03 pH units) and in Group II (0.24 +/- 0.05 pH units, P:NS). However, the accumulation of hydrogen ion during the second hour was significantly greater in Group I (+128.0 +/- 21.4 nm/liter) than in Group II (+36.6 +/- 9.0 nm/liter, P less than 0.001). Thus, myocardial acidosis was reduced during the administration of blood cardioplegia when compared to a bicarbonate-buffered crystalloid solution. The salutary effects of blood cardioplegia on myocardial metabolism stem from blood's significant buffering capacity and its ability to deliver oxygen.

The influence of cholecystokinin, vasoactive intestinal peptide and secretin on pancreatic and biliary secretion in laying hens

White Leghorn hens, 14-29 weeks old, were surgically fitted with cannulas for collecting pancreatic and biliary secretions, and a jugular cannula for continuous infusion of either cholecystokinin (CCK), vasoactive intestinal peptide (VIP), or secretin. As compared to secretory levels during saline infusion, CCK significantly stimulated biliary flow and biliverdin concentration in bile; VIP significantly depressed biliverdin concentration but enhanced bicarbonate secretion in both pancreatic and biliary secretions, and also increased total pancreatic flow. Secretin depressed biliary flow and increased pancreatic bicarbonate release. The principal hormonal regulator of biliary secretion appears to be CCK, and that of pancreatic secretion to be VIP.

Chemical denervation of the myenteric plexus of the muscular stomach of turkeys

1. The thin caudoventral muscle (TCM) of the muscular stomach of domestic turkeys was surgically exposed and painted with solutions of saline or 0.1, 0.25, 0.5, and 1.0% benzalkonium chloride (BC), a cationic surfactant shown to irreversibly damage neurons but not muscle tissue in mammals. 2. Following fluoroscopic observations of gastric motility for 2 weeks, turkeys were euthanized, the entire muscular stomach was excised and weighed, and serial frozen sections of the TCM were taken for evaluation of the number and size of neurons in the myenteric plexus. 3. Treatment with 0.5 and 1.0% BC resulted in loss of motility in the TCM, significant hypertrophy (P less than 0.001) of the CTM, a 70% decrease in number and 60% decrease in size of myenteric neurons, and a 4-fold increase in thickness of the serosa, compared with saline-treated controls.

Intraoperative assessment of the physiologic significance of coronary stenosis in humans

Coronary angiography is generally considered the gold standard in assessing the significance of coronary stenosis. The inadequacy of coronary angiography has frequently been demonstrated by intraoperative findings that differ from those projected by the catheterization report. To better assess the physiologic significance of coronary stenosis, we measured intramyocardial pH intraoperatively in 50 myocardial segments supplied by stenotic coronary arteries before and after revascularization in 42 patients undergoing coronary artery bypass grafting. The hemodynamic, electrocardiographic, and pH responses to atrial pacing were recorded intraoperatively before and after revascularization. The coronary angiograms, performed within 3 months before bypass grafting, were reviewed by a single independent observer. Preoperative and postoperative radionuclide ventriculograms were performed and also reviewed by an independent observer. In response to atrial pacing, a fall exceeding 0.02 pH units was considered to represent ischemia and was observed in 28 segments. Patients exhibiting this response comprised Group I. Twenty-two segments demonstrated a fall of less than 0.02 pH units or a rise in pH in response to atrial pacing. Patients having this response comprised Group II. Segments in Group I responded dramatically to revascularization, with the pH during atrial pacing rising from -0.09 +/- 0.01 to -0.02 +/- 0.01 (p less than 0.001). Nine patients demonstrated ischemic S-T changes during atrial pacing, all in Group I. Pre-pacing hemodynamic parameters were similar in both groups. Group I patients, however, demonstrated a significant fall in mean arterial pressure during atrial pacing, from 92.0 +/- 3.0 to 78.4 +/- 3.3 mm Hg (p less than 0.001) whereas Group II patients did not. Twelve segments that angiograms indicated were supplied by critically stenotic vessels (greater than 75%) failed to demonstrate a significant fall in their pH during atrial pacing. In these segments, intraoperative findings and postoperative results corroborated the metabolic findings. Coronary angiography, therefore, was only 45% specific in assessing physiologically significant obstructions. The degree of segmental wall motion abnormalities likewise correlated poorly with the pH changes. Unlike coronary angiography, the response of intramyocardial pH to pacing is an accurate metabolic tool to assess myocardial ischemia in humans.

Influence of cholecystokinin, vasoactive intestinal peptide and secretin on plasma concentration of avian pancreatic polypeptide in laying hens

The influence of saline infusion (i.v.) followed by infusion of either cholecystokinin, vasoactive intestinal peptide, or secretin on plasma concentration of avian pancreatic polypeptide (aPP) was studied in sixteen 18-26-week old Single Comb White Leghorn hens. Three concentrations were used for each hormone. Blood was drawn after both saline and hormone infusions and assayed for aPP content. No significant influence of any of the three hormones on plasma aPP level was found in either fed or fasted hens.

Behavioural methods in the treatment of sleep disorders--a pilot study

The efficacy of behavioural methods of treatment for severe sleep disorders was examined in a pilot study involving 35 children aged 1-5 years. Improvement occurred in 77%. Methodological issues concerning the selection of children for treatment, selecting adequate controls and outcome measures, and using parents as therapists, are discussed.

The influence of avian pancreatic polypeptide on gastric secretion and motility in laying hens

The effects of pancreatic polypeptide (PP) on digestive functions have been studied extensively in mammals. The only two previous studies on the effects of PP on avian (aPP) gastrointestinal function employed bolus injections (i.v.) of the hormone, which may have resulted in nonphysiological plasma levels of aPP. The present study was to determine the effect of aPP infused (iv) at levels simulating postprandial plasma concentrations. Young laying hens were prepared with chronic proventricular and jugular cannulas and with strain gauge transducers sutured to the serosa of the gizzard. In each experiment, a control saline infusion was followed by infusion sufficient to achieve either 7.5 or 15 ng aPP/ml of plasma. Volume, pH, and pepsin content of gastric secretions and frequency and amplitude of gastric contractions were determined. At 15 ng aPP/ml of plasma, secretory volume (P less than .01) and contractile frequency (P less than .001) were significantly depressed as compared to similar data during the saline infusion. At 7.5 ng aPP/ml of plasma, only contractile frequency (P less than .01) was depressed.

Observations on 100 patients with continuous intraoperative monitoring of intramyocardial pH. The adverse effects of ventricular fibrillation and reperfusion

Intramyocardial pH and temperature data recorded in 100 patients undergoing cardiac operations were analyzed to elucidate the effects of ventricular fibrillation and reflow. All patients underwent a single period of aortic clamping. Systemic hypothermia (25 degrees C) and intermittent cold crystalloid K+ cardioplegia were employed for myocardial protection. Baseline myocardial pH was 6.88 +/- 0.03 at a temperature of 36.5 degrees +/- 0.2 degree C. During the period of hypothermic ventricular fibrillation prior to aortic clamping, ventricular fibrillation did not affect myocardial pH in 45 patients (Group 1). In 21 patients (Group 2), it caused a significant drop in intramyocardial pH despite cooling. Group 2 patients had a higher incidence of valvular heart disease and left ventricular hypertrophy. They also exhibited low intramyocardial pH values during the subsequent periods of aortic clamping and reflow, indicating inadequate myocardial protection. During the period of reflow, reperfusion acidosis (pH less than 6.8 at 32 degrees C) was encountered in 39 patients (Group B) as opposed to 37 patients (Group A) whose pH remained well above 6.8 during that period. Group B patients had a higher incidence of valvular heart disease and left ventricular hypertrophy, tended to have more ischemic anterior walls prior to cardiopulmonary bypass, sustained longer periods of aortic clamping, had intramyocardial pH evidence of suboptimal protection during aortic clamping, were affected more adversely by ventricular fibrillation during reflow, and tended to have a higher operative mortality. Thus: Depending on the underlying myocardial disease, the adequacy of protection during aortic clamping, and the conditions of reflow, intramyocardial pH in man can fall significantly during ventricular fibrillation and reflow. The metabolic correlate of injury with reflow is a reperfusion acidosis that can reach as low as pH 5.98. When encountered, reperfusion acidosis can be minimized by prompt defibrillation.

Discriminant validity of the MMPI for borderline personality disorder

This study explores the discriminant validity of the MMPI in relationship to the DSM-III and the Diagnostic Interview for Borderlines (DIB) constructs of Borderline Personality Disorder (BPD). A two-way analysis of variance model assessed differences between inpatients (n = 42) and outpatients (n = 42) and between BPD and nonBPD patients. We compare the best discriminant model for the current samples with previous BPD discriminant functions. The present study assesses a wider range of psychopathology in which the MMPI appears to be relatively insensitive to the BPD construct while retaining the high specificity reported in previous studies. Implications for the use of the MMPI as a diagnostic instrument are discussed.

Delayed-onset heparin-induced thrombocytopenia. A potentially malignant syndrome

Delayed-onset thrombocytopenia developed in 12 patients while they were receiving either prophylactic or therapeutic heparin. Five of the patients had thrombocytopenia alone, and seven had thromboembolic complications which contributed to the death of one patient. These complications included deep venous thrombosis (four patients), pulmonary embolism (three patients), myocardial infarction (one patient), sagittal sinus thrombosis (one patient), and femoral artery occlusion (one patient). The diagnosis of heparin-induced thrombocytopenia was delayed for between one and 13 days after the initial complicating event. All patients had heparin-dependent platelet-aggregating factor in their plasma. The characteristics of the heparin-dependent platelet-aggregating reaction were the same in all patients, but the nadir of thrombocytopenia was lower in patients with delayed-onset heparin-induced thrombocytopenia and complicating thromboembolism. These findings highlight the necessity for early recognition of this syndrome and for the prompt withdrawal of heparin to prevent considerable patient morbidity.

Alcoholism among Aboriginal people

Much has been spoken and written about alcohol problems in Aboriginal communities, but little has been achieved in dealing with these problems effectively, as is clearly illustrated by the statistics in this article, which summarizes the over-all situation in New South Wales, analyses its historical development, and shows its present catastrophic proportions. An approach, based on 13 years of active and intensive involvement in this particular field, is presented which if properly implemented, could greatly alleviate this pressing problem.