Targeting eIF4A triggers an interferon response to synergize with chemotherapy and suppress triple-negative breast cancer

Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A with zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages toward an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 and Fgfr1, and induces an interferon (IFN) response uniformly across models. The induction of an IFN response is partially due to the inhibition of Sox4 translation by zotatifin. A similar induction of IFN-stimulated genes was observed in breast cancer patient biopsies following zotatifin treatment. Surprisingly, zotatifin significantly synergizes with carboplatin to trigger DNA damage and an even heightened IFN response, resulting in T cell-dependent tumor suppression. These studies identified a vulnerability of eIF4A in TNBC, potential pharmacodynamic biomarkers for zotatifin, and provide a rationale for new combination regimens consisting of zotatifin and chemotherapy or immunotherapy as treatments for TNBC.

Targeting EIF4A triggers an interferon response to synergize with chemotherapy and suppress triple-negative breast cancer

Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A by Zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages towards an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that Zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 and Fgfr1, and induces an interferon response uniformly across models. The induction of an interferon response is partially due to the inhibition of Sox4 translation by Zotatifin. A similar induction of interferon-stimulated genes was observed in breast cancer patient biopsies following Zotatifin treatment. Surprisingly, Zotatifin significantly synergizes with carboplatin to trigger DNA damage and an even heightened interferon response resulting in T cell-dependent tumor suppression. These studies identified a vulnerability of eIF4A in TNBC, potential pharmacodynamic biomarkers for Zotatifin, and provide a rationale for new combination regimens comprising Zotatifin and chemotherapy or immunotherapy as treatments for TNBC.

Addressing social polarization through critical thinking: Theoretical application in the “Living Well With Difference” course in secondary schools in England

Responding to international calls for critical thinking programs to address social polarisations and extremism through education, this article examines the cognitive and socio-psychological foundations of a critical thinking programme for secondary schools in England called “Living Well With Difference” (LWWD). The aim of LWWD is to develop critical thinking about issues of social polarisation, prejudice and any kind of extreme thinking. These issues often involve the interaction of emotion and thinking, which is understood using a dual systems framework, illustrated with examples of course methodology and content. The learning process aims to promote more cognitively flexible, complex and integrated thinking, measured by integrative complexity, and is supported by meta-awareness to enable emotion management. The aim is for participants to engage with difficult social issues through structured group activities, while becoming aware of social, emotional, textual, visual and rhetorical influences to increase Media Information Literacy, as a foundation for engaging with differing perspectives in order to reduce barriers between groups in society.

Abstract 1426: Multiomic analysis identifies CPT1A and fatty acid oxidation as a potential therapeutic target in platinum-refractory high grade serous ovarian cancer

Platinum-based DNA cross-linking agents are widely used anti-cancer drugs. Tumor resistance to platinum compounds is a major determinant of patient survival, including in high grade serous ovarian cancer (HGSOC). Remarkably, despite >30 years of literature on platinum responses in human cancer, none of these findings is used clinically as a predictive biomarker to stratify patients for platinum resistance, nor exploited therapeutically to treat platinum-resistant disease. Thus, understanding mechanisms of platinum resistance is an urgent goal, both to identify predictive biomarkers of platinum response (to spare patients with platinum-resistant tumors futile platinum therapy) and to develop efficacious therapies for platinum-resistant disease. To better understand mechanisms underlying platinum resistance in HGSOC, we performed comprehensive, dynamic (+/-carboplatin), multiomic profiling of DNA, RNA, protein and post-translational modifications (phosphorylation, ubiquitination, acetylation) to identify the cellular networks that respond to platinum treatment and associate with platinum resistance in three HGSOC intra-patient cell line pairs (PEA1S/PEA2R, PEO1S/PEO4R, PEO14S/PEO23R). The cell line pairs were derived from ascites or pleural effusions (Langdon et al., 1988) from three patients both before (PEA1S, PEO1S, PEO14S) and after (PEA2R, PEO4R, PEO23R, respectively) their tumors became clinically platinum resistant (i.e., in vivo development of resistance). The molecular profiles revealed extensive responses to carboplatin and differential responses between platinum-sensitive and platinum-resistant cells. Higher oxidative phosphorylation and fatty acid oxidation (FAO) pathway expression were observed in the platinum-resistant cells, which was further validated in patient-derived xenograft (PDX) models. We show that pharmacologic inhibition or CRISPR knockout of CPT1A, which represents a rate limiting step of FAO, sensitize HGSOC cells to platinum. Thus, FAO, and CPT1A in particular, represent a candidate therapeutic target to overcome platinum resistance in HGSOC.

Citation Format: Hong Wang, Dongqing Hugang, Shrabanti Chowdhury, Sara Savage, Richard Ivey, Jacob Kennedy, Jeffrey Whiteaker, Chenwei Lin, Xiaonan Hou, Catherine Huntoon, Uliana Voytovich, Zahra Shire, Qing Yu, Steven Gygi, Andrew Hoofnagle, Zachary Herbert, Anna Calinawan, Larry Karnitz, S. John Weroha, Scott Kaufmann, Bing Zhang, Pei Wang, Michael Birrer, Amanda Paulovich. Multiomic analysis identifies CPT1A and fatty acid oxidation as a potential therapeutic target in platinum-refractory high grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1426.

Graphene active sensor arrays for long-term and wireless mapping of wide frequency band epicortical brain activity

Graphene active sensors have demonstrated promising capabilities for the detection of electrophysiological signals in the brain. Their functional properties, together with their flexibility as well as their expected stability and biocompatibility have raised them as a promising building block for large-scale sensing neural interfaces. However, in order to provide reliable tools for neuroscience and biomedical engineering applications, the maturity of this technology must be thoroughly studied. Here, we evaluate the performance of 64-channel graphene sensor arrays in terms of homogeneity, sensitivity and stability using a wireless, quasi-commercial headstage and demonstrate the biocompatibility of epicortical graphene chronic implants. Furthermore, to illustrate the potential of the technology to detect cortical signals from infra-slow to high-gamma frequency bands, we perform proof-of-concept long-term wireless recording in a freely behaving rodent. Our work demonstrates the maturity of the graphene-based technology, which represents a promising candidate for chronic, wide frequency band neural sensing interfaces.

Abstract 5118: Proteogenomics characterization of HPV-negative head and neck squamous cell carcinomas

Patients with head and neck squamous cell carcinomas (HNSCCs) are treated with surgery, radiation, chemotherapy, and limited targeted therapies. Compared to human papillomavirus (HPV)-positive HNSCCs, HPV-negative cases have worse treatment response and prognosis and represent an unmet clinical need. We performed comprehensive proteogenomic characterization of tumor specimens, matched normal adjacent tissues (NATs), and blood samples from 109 HPV-negative HNSCC patients. This cohort is dominated by tumors from oral cavity (45, 41%) and larynx (49, 45%). Somatic mutation and somatic copy number analyses validated previously reported genomic aberrations in HPV-negative HNSCC. Proteomics analysis linked p53 loss of heterozygosity to increased expression of EPCAM, a stemness marker. Additionally, FAT1 truncation mutations were associated with increased expression of proteins involved in keratinization, a key feature of SCC differentiation. Deletions of 3p and 9p led to the loss of genes encoding p16, chemokine receptors, and interferon/JAK/STAT signaling pathway proteins, whereas amplifications of 3q and 11q led to overexpression of proteins involved in cell proliferation and anti-apoptosis pathways. Comparative analysis of tumor and NAT proteomes and phosphoproteomes identified putative diagnostic biomarkers and druggable targets, and proteogenomic integration further identified putative neoantigens. Tumor site-specific characterization associated epigenetic silencing of neurofilaments with laryngeal but not oral cavity SCC. Protein targets of FDA approved or investigational drugs for HNSCC treatment showed high inter-tumor heterogeneity in their protein abundances. DNA copy number and RNA expression level were good surrogates of protein abundance for some targets, such as EGFR and PD-L1, but they failed to reflect protein levels or kinase activities for other targets, such as MMP9 and MTOR. Thus, there is a critical need for protein biomarker-driven treatment stratification. Deconvolution of bulk tumor gene expression data revealed an immune-hot subgroup and an immune-cold subgroup. Immune-hot tumors broadly overexpressed multiple immune checkpoints including PD-L1, IDO1, and CTLA4, underscoring the necessity of combination immune checkpoint inhibition to improve treatment efficacy. Immune-cold tumors were characterized by smoking, chromosomal instability, and activation of the CDK4/6-pRb axis, suggesting they could be targeted by CDK4/6 inhibitors. We also noted that EGFR-amplified tumors frequently harbor copy number aberrations of downstream signaling components of the EGFR pathway. This may explain the low response rate of EGFR-amplified tumors to EGFR inhibitors, and targeting multiple pathway components, including EGFR, PIK3CA and STAT3, may be required for these tumors. In summary, our integrative proteogenomic characterization revealed multiple novel insights into the pathogenesis and treatment of HPV-negative HNSCCs.

Citation Format: Chen Huang, Lijun Chen, Yize Li, Sara Savage, Michael Schnaubelt, Felipe V. Leprevost, Marcin Cieslik, Yongchao Dou, Bo Wen, Jonathan T. Lei, Kai Li, Eric Jaehnig, Zhiao Shi, Meenakshi Anurag, Jianbo Pan, Yingwei Hu, Rodrigo V. Eguez, David J. Clark, Matthew Wyczalkowski, Saravana M. Dhanasekaran, Chandan Kumar, Antonio Colaprico, Karsten Krug, Michael Gillette, D. R. Mani, Seungyeul Yoo, Jiayi Ji, Xiaoyu Song, Weiping Ma, Xi Steven Chen, Alex Pico, Nathan J. Edwards, Scott D. Jewell, Mathangi Thiagarajan, Emily S. Boja, Henry Rodriguez, Andrew Sikora, Pei Wang, Matthew Ellis, Gilbert S. Omenn, Li Ding, Alexey I. Nesvizhskii, Adel K. EI-Naggar, Daniel W. Chan, Hui Zhang, Bing Zhang, Clinical Proteomic Tumor Analysis Consortium. Proteogenomics characterization of HPV-negative head and neck squamous cell carcinomas [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5118.

The role of the NFAT signaling pathway in retinal neovascularization

PURPOSE

The purpose of the present study was to investigate the role of nuclear factor of activated T cells (NFAT), a transcription factor downstream of VEGF, in angiogenic cell behaviors of human retinal microvascular endothelial cells (HRMEC), and to assess the efficacy of NFAT signaling inhibitors in a rat model of oxygen-induced retinopathy (OIR).

METHODS

Human retinal microvascular endothelial cells were treated with VEGF in the presence or absence of the NFAT inhibitor of NFAT-calcineurin association-6 (INCA-6), and NFAT translocation was evaluated using immunocytochemistry (ICC). Human retinal microvascular endothelial cells were treated with increasing doses of INCA-6, and cell proliferation and tube formation were assessed. Rats subjected to OIR were administered increasing doses of INCA-6 or the CN inhibitor FK-506, and the retinal neovascular area was measured.

RESULTS

Nuclear factor of activated T-cells c1 was translocated to the nucleus of HRMEC treated with VEGF, and INCA-6 treatment blocked translocation. Inhibitor of NFAT-calcineurin association-6inhibited HRMEC proliferation and tube formation in a dose-dependent manner. Both INCA-6 and FK-506 treatment significantly reduced pathologic neovascularization in OIR.

CONCLUSIONS

This investigation has demonstrated that in HRMEC, NFATc1 is activated downstream of VEGF signaling and NFAT signaling plays a key role in angiogenic cell behaviors. In addition, NFAT inhibition is shown to be highly efficacious in an OIR model. These findings indicate that the NFAT signaling pathway may serve as a suitable therapeutic target for the treatment of neovascular eye disease.

Dissociation of explicit and implicit long-term memory consolidation in semantic dementia: a case study

We report a case study of a semantic dementia patient, whose episodic memory consolidation was tested over a 2-month period. The results reveal that despite early retention of information, the patient lost all explicit information of the newly learnt material after 2 weeks. By contrast, he retained implicit word information even after a 4-week delay. These findings highlight the critical time window of 2-4 weeks in which newly learnt information should be re-encoded in rehabilitations studies. The results also indicate that learnt information can be still accessed with implicit retrieval strategies when explicit retrieval fails.

Cholinergic denervation attenuates phencyclidine-induced c-fos responses in rat cortical neurons

The cortical cholinergic innervation, which is important for memory and cognition, has been implicated in schizophrenia. To experimentally analyze such a possible role of the cholinergic system, we have used the dissociative drug phencyclidine (PCP), known to produce schizophrenia-like psychosis in humans, to model aspects of schizophrenia in rats. We previously showed that induced cortical cholinergic hypofunction leads to enhanced PCP-induced locomotor activity and attenuated social interaction. After PCP, rats lacking cortical cholinergic innervation also show impaired declarative memory. To directly study the role of the basalo-cortical cholinergic projections for PCP-induced neural activation in different cortical areas, we have now monitored the rapid (30 and 60 min) effects of low doses of PCP (2 and 3mg/kg) on neural activation as reflected by transcriptional activation of c-fos in cortical areas, using quantitative in situ hybridization. We find an almost pan-cortical neural induction of c-fos mRNA with doses of PCP low enough not to alter levels of either BDNF or Nogo receptor mRNA levels. Specific unilateral lesioning of the uncrossed cholinergic projections to the cortical mantle by 192-IgG-saporin immunotoxin delivery to nc basalis (NBM) caused a striking ipsilateral decrease of the PCP-induced cortical c-fos mRNA induction, restricted to areas which had become effectively denervated. Because PCP at low doses is unlikely to directly influence cortical neurons, we suggest that it acts by activation of the cholinergic input, which in turn leads to cortical c-fos mRNA increases. Our results are compatible with a role for the cholinergic system in symptoms of schizophrenia, by showing that the basalo-cortical cholinergic projections are needed in order for PCP to have full activating effects on cortical neurons.

Orbitofrontal dysfunction discriminates behavioral variant frontotemporal dementia from Alzheimer's disease

BACKGROUND

Behavioral variant frontotemporal dementia (bvFTD) patients show prefrontal cortex dysfunction and atrophy.

METHODS

We investigated whether executive function in conjunction with prefrontal cortex atrophy discriminates bvFTD and Alzheimer's disease (AD) patients efficiently at presentation.

RESULTS

AD and bvFTD patients were distinguishable by 89.5% on their performance of 3 executive tasks: the Hayling Test of Inhibitory Control, Digit Span Backward and Letter Fluency. Similarly, scan ratings showed that orbitofrontal cortex (OFC) and dorsolateral prefrontal cortex regions distinguish both patient groups. More importantly, employing the Hayling error score in conjunction with the OFC atrophy rating showed that 92% of patients can be correctly classified into bvFTD and AD.

CONCLUSION

A combination of OFC and disinhibition measures appears to be a powerful diagnostic tool in differentiating bvFTD from AD patients in this preliminary study.

Use of independent genome-wide assays to discover HOXA signature in colon and rectal cancers and validate a role in tumorigenesis

e15014

Background: Rectal cancer differs from colon cancer in terms of prognosis. Here we present genome-wide expression analysis of 79 colon and rectal tumors and gene dosage analysis of 34 archival colorectal tumors in paraffin (FFPE). Methods: Expression data were acquired ( http://expo.intgen.org/geo/home.do ) from Affymetrix experiments analyzed with GeneSpring software version 7.3 (Silicon Genetics, CA). Expression data were normalized ’per chip’ normalized to the 50th percentile of all values; and ’per gene’ normalized to the median expression level across all samples. Expression Project for Oncology (expO) samples included colon (n=50) and rectum (n=29). Differentially expressed genes were identified by parametric test for which variances were not assumed equal (Welch ANOVA). Array comparative genomic hybridization (aCGH) were performed separately on an independent set of FFPE colorectal tumors (n=34) by 244 K microarrays for CGH, Agilent Technologies, CA and with platform embedded analyses tools of CGH Analytics software and ADM-1 bioinformatics. Functional assay by knockout of HOXA9 promoter by lentiviral sh-RNAi construct was performed on colon cancer cell lines shown to have increased HOXA9 dosage and expression. Results: The analysis of expO colon and rectal cancers generated 42 genes with significant differential expression, 26 showed an increased expression of > 2 fold in colon versus rectal samples. Transcription factor family HOXA9 was the most highly expressed (3.8 fold) in colon versus rectal cancer. The aCGH data showed a low level gain of the HOXA gene to be the most frequent dosage alteration (38%). Validation by IHC and qRT-PCR showed 80% and 76% concordance, respectively. Functional assay by sh-RNAi in cell lines (compared to vehicle only) showed marked decrease in cellular viability (40 to 60%), marked morphologic change and a significantly increased apoptotic rate. Conclusion: Multiple genome-wide assays have identified HOXA9 as differentially dosed and expressed in colon and rectal tumors. Compelling functional data from sh-RNAi experiments suggests a tumorigenic role for HOXA9 in altered apoptosis.

No significant financial relationships to disclose.

Clinical evaluation of nitric oxide responses to anti-VEGF therapy with bevacizumab

14039

Background: Anti-vascular endothelial growth factor (anti-VEGF) therapy has been linked to hypertension (HTN) and arterial thrombo-embolic events that may involve changes in nitric oxide (NO) bioavailability. Methods: 25 patients (pts) with advanced cancer, normal renal function and blood pressure (BP), no increased risks for anti-VEGF toxicities, and not on medications known to confound biomarker studies (including anti-hypertensives) were treated with bevacizumab (BV) 15mg/kg d1, then 10mg/kg q2 week. Prior to biomarker assessment, all patients were placed on a calorie-, nitrate-, and salt-restricted diet for 72 hr. All measures were taken pre-treatment (preRx) and on day 28 of treatment (onRx). Dependant variables included; a) Brachial artery reactivity (BAR) following hyperemic flow stimulus (endothelium-dependent) and sub-lingual nitroglycerine (NTG; endothelium-independent); b) exhaled and plasma/urine total NO2/NO3 using chemiluminescence (Sievers 280NOA) with either KI or VCl3 in HCl as the reductants; c) blood pressure. Additionally, we measured multiple regulators of vascular tone and injury. Comparisons were analyzed using Spearman signed rank tests. Results: Of 25 pts (16 F, 9 M) treated, 21 patients were fully evaluable. Significant changes or strong trends were observed upon comparing preRx vs. onRx for BP (SBP +12.4, DBP +5.6, MAP +7.9 mm Hg), and flow-mediated BAR (-2.0%) with no changes in hyperemic flow/shear stimulus or smooth muscle function (BAR NTG), indicating a decrease in brachial artery endothelial responsiveness. Exhaled NO decreased (-0.8% d1vs d28 and -0.6% pre/post infusion day1). Measurement and data analysis of urinary/plasma NO2/NO3, as well as angiogenic markers, are almost complete and will be reported. Conclusions: After one month of treatment, BV increased BP and decreased endothelium- dependent BAR and exhaled NO, suggesting potentially broad, mechanism-based effects on NO bioavailability in patients.

[Table: see text]

A phase I, open-label study of the safety and pharmacokinetics (PK) of pazopanib (P) and lapatinib (L) administered concurrently

3088

Background: P is a potent tyrosine kinase inhibitor of VEGF-R1, -R2, and R3, PDGF-α/β, and c-Kit. L is a potent inhibitor of ErbB1 and ErbB2 tyrosine kinases. Several lines of evidence support combined inhibition of VEGFR and Erb in the treatment of malignancies. Methods: Patients (pts) with solid tumors received P and L daily. Safety, limited PK, biomarkers, and clinical activity were evaluated. Dose escalation occurred in cohorts of 3–6 pts based on DLT. Results: Thirty-three pts received L/P doses of 750/250 (n=4), 750/500 (n=6), 1000/250 (n=3), 1000/400 (n=2), 1000/500 (n=4), 1250/250 (n=6), 1250/400 (n=5) and 1500/200 (n=3) mg once daily (qd). Preliminary mean plasma P concentrations 24 h after administration (C24) on Day 22 were ∼19 μg/mL and 23 μg/mL after administration of 250 mg and 500 mg, respectively. These values are similar to mean C24 values observed after administration of 800 mg P alone (23.1 μg/mL). Plasma L concentrations at 750 - 1500 mg qd were similar to those observed after monotherapy. The most frequent AE’s were diarrhea (Grade (G)1 n=10, G2 n=2, G3 n=3), fatigue (G1: n=7, G2 n=5, G4 n=1), nausea (G1 n=9, G2 n=2), anorexia (G1 n=8, G2 n=3), vomiting (G1 n=9), hair depigmentation (n=7), rash (G1 n=6, G2 n=1) and abdominal cramps (G1 n=3, G2 n=2, G3 n=1). Prolonged disease stabilization of > 16 wks (median 21.5 wks) occurred in 10 pts (RCC n=3, CRC n=3, GIST n=1, mesothelioma n=1, adenocarcinoma GE junction n=1, aggressive fibromatosis n=1). 3 pts (renal cancer n=2, and giant cell tumor of the bone n=1) demonstrated tumor shrinkage of < 30% (i.e. SD by RECIST). Conclusions: Concurrent administration of pazopanib and lapatinib was generally well tolerated. Coadministration of lapatinib may alter the PK of pazopanib.

[Table: see text]

Upper urinary tract metastases from adenocarcinoma of the colon

An unusual presentation of colorectal metastasis to the upper urinary tract is reported. The metastasis manifested as a filling defect seen during antegrade pyelography. Cytologic evaluation of aspirated material demonstrated metastatic colonic adenocarcinoma. A dilated collecting system may be caused by intraluminal material including tumor and blood clots. Whenever fixed filling defects are encountered, urine cytology should be sent even in the absence of renal parenchymal involvement by tumor. The cytological evaluation may allow for prompt diagnosis and treatment.

Exploring distributive justice in health care

The allocation of resources to providers and the way in which the resources are then prioritised to specific service areas and patients remain the critical ethical decisions which determine the type of health system a community receives. Health care providers will never be given enough resources to satisfy all the demands placed upon them by a community that is becoming increasingly informed and demanding. This paper discusses the matter of justice as it relates to the distribution of health resources. It translates the theoretical constructs of distribution into a practical situation that arose at The Geelong Hospital. It is important to emphasise that the aim of giving the example is not necessarily to provide the right answer but rather to assist in determining what ought to be the questions.

The effects of collagen hydrolysat on symptoms of chronic fibromyalgia and temporomandibular joint pain

Twenty (20) people who had medically diagnosed fibromyalgia for two to 15+ years participated in and completed a 90-day evaluation to determine effects of collagen hydrolysat on symptoms of chronic fibromyalgia, with twelve reporting temporomandibular joint pain. Collagen hydrolysat is a food supplement that is available without prescription, with no known side effects. Participants were evaluated initially and then at 30-, 60-, and 90-day periods. Final results were obtained and comparisons made. The average pain complaint levels decreased significantly in an overall group average, and dramatically with some individuals. It was concluded that patients with fibromyalgia and concurrent temporomandibular joint problems may gain symptomatic improvement in their chronic symptoms by taking collagen hydrolysat.

Improving credibility of instructions in the balanced placebo design: a misattribution manipulation

Research using the balanced placebo design seeks to differentiate the physiological and psychological effects of drinking alcohol. Questions regarding the validity of the design center about experimenter instructions, particularly in the antiplacebo cell at higher blood alcohol content (BAC) levels. This study tested the plausibility of two misattribution strategies designed to reduce the conflict between experimenter instructions and internal cues of drunkenness. Forty-two participants (BAC = .055) were told that they received no alcohol, with internal cues of drunkenness said to be produced by a (sham) second drug, a (placebo) tachistoscopic display, or no misattribution given. The placebo drug group reported less alcohol intoxication without reporting less physical impairment than the control or tachistoscopic groups. Doubt of instructions was expressed more frequently in the control group than in the placebo drug group. Mean time to first reported doubt of experimenter instructions was longer for the placebo drug group. A manipulation check designed to account for demand effects indicated that instituting the pharmacologic misattribution increased the success of the manipulation over the control group. Providing a credible attribution for internal symptoms of drunkenness makes experimenter's instructions more credible, improving the validity of the antiplacebo cell of the balanced placebo design.

Increased complications in noninsulin-dependent diabetic patients treated with insulin versus oral hypoglycemic agents: a population study

A cross-sectional population study was performed in a cohort of 890 non-insulin-dependent diabetes mellitus (NIDDM) patients residing in the greater Denver metropolitan region. Its purpose was to evaluate the relationship between insulin and oral hypoglycemic agents (OHAs) with regard to metabolic control and diabetic complications. The mean glycosylated hemoglobin for patients treated with insulin was 12.0 +/- 0.15% versus 11.4 +/- 0.14% (p < .03) for OHA. The difference in fasting blood sugar for the insulin-treated group (195.0 +/- 3.5 mg/dl) versus the OHA-treated group (194.0 +/- 2.9 mg/dl) was not statistically significant. Categorical increases in urinary albumin excretion were associated positively within insulin versus OHA therapy (p < .0001). Patients treated with insulin therapy had a higher frequency of peripheral vascular disease (insulin therapy, 14%; OHA therapy, 10%; p < .05); neuropathy (insulin therapy, 55%; OHA therapy, 37%; p < .0001); and retinopathy (insulin therapy, 71%; OHA therapy, 45%; p < .0001). The frequency of cardiovascular disease was equivalent in the two groups (17% versus 13%). In protocols correcting for diabetes duration, glycosylated hemoglobin, and gender in a multivariate model, the use of insulin still was related significantly to increases in urinary albumin excretion (p < .01), retinopathy (p < .0001), and neuropathy (p < .0008). In a subgroup of individuals with diabetes duration > 10 years (n = 211 for insulin treatment, n = 118 for OHA treatment), the frequency of neuropathy still was significantly higher in the insulin group (63% vs 49%; p < .016) as was retinopathy (85% vs 58%; p < .0001). Overt albuminuria also was more significant in the insulin-treated patients (p < .04). In summary, the NIDDM patients treated with insulin had more nephropathy, retinopathy, and neuropathy than did NIDDM patients treated with OHA, independent of duration of diabetes, fasting blood glucose, glycosylated hemoglobin, age, and blood pressure level. These results in NIDDM patients may be due to contributions from worse blood glucose control at an earlier stage in the patients' diabetes and/or the mitogenic, atherogenic, thrombogenic, and vascular permeability effects of insulin.

Exercise and exhaustion effects on glycogen synthesis pathways

Female Sprague-Dawley rats were infused with [1-13C]glucose to measure the effect of endurance training and the effect of various metabolic conditions on pathways of hepatic glycogen synthesis. Four metabolic states [sedentary (S), trained (T), sedentary exhausted (SE), and trained exhausted (TE)] were studied. T and TE rats were trained on a motor-driven treadmill (30 m/min, 15% grade, 1.0 h/day, 5 days/wk) for 8-10 wk. After a 24-h fast, SE and TE rats were run to exhaustion (sedentary average = 78 min, trained average = 155 min) at a training pace and immediately infused with labeled glucose for 2 h. S and T rats were infused after a 24-h fast. After infusion, tissues were removed and glycogen was isolated and hydrolyzed to glucose. The glucose was measured for distribution of 13C by using nuclear magnetic resonance. Glycogen was synthesized predominantly by the indirect pathway for all metabolic states, indicating that infused glucose was first metabolized primarily in the peripheral tissue. The direct-pathway utilization was greater in rested S than in rested T animals (30 vs. 14%); however, for exhausted animals, the trained use of the direct pathway was greater (22 vs. 9%). Both TE and rested T animals utilize the indirect pathway a comparable amount. Sedentary animals, on the other hand, dramatically decreased utilization of the direct pathway, with exhaustive exercise changing from 30 to 9%. The results indicate that endurance training modifies glucose utilization during glycogen synthesis after fasting and exhaustive exercise.

Urinary albumin excretion as a predictor of diabetic retinopathy, neuropathy, and cardiovascular disease in NIDDM

OBJECTIVE

The relationship between urinary albumin excretion (UAE) and diabetic complications in NIDDM has not been studied in a large American population. The demonstrated relationship between increased UAE and the development of retinopathy, nephropathy, and neuropathy in IDDM makes this an important issue to also be studied in NIDDM patients.

RESEARCH DESIGN AND METHODS

A large population study of 947 NIDDM patients living predominantly in a metropolitan area was undertaken. Three categories of UAE, namely, normal albuminuria (< 20 micrograms/min), microalbuminuria (20-200 micrograms/min), and overt albuminuria (> 200 micrograms/min) were compared with 1) retinopathy as assessed by stereoscopic fundus photographs; 2) cardiovascular disease as assessed by a history of cardiac disease or stroke; ischemic changes on exercise treadmill testing; Q wave myocardial infarction; Estes, Sokolow, or Cornell criteria for left ventricular hypertrophy; positive Rose questionnaire for angina; and an abnormal Doppler exam for peripheral vascular disease; and 3) neuropathy as assessed by neurological symptom and disability scores, autonomic function testing, and quantitative sensory exams involving thermal and vibratory sensation. Selected patient characteristics were then evaluated to determine their effects on the presence of diabetic complications using univariate analyses. Multiple logistic regression analyses were then performed to determine the independent effect of UAE on these diabetic complications.

RESULTS

chi 2 analyses revealed that UAE was significantly associated with the presence of retinopathy (P < 0.001), neuropathy (P < 0.001), and cardiovascular disease (P < 0.001). In the multiple logistic regression analyses, UAE had strong independent associations with retinopathy, neuropathy, and cardiovascular disease.

CONCLUSIONS

Thus, increasing UAE in this large NIDDM population in the U.S. was associated with an increased prevalence of diabetic retinopathy, neuropathy, and cardiovascular disease. This suggests that UAE may be more than an indicator of renal disease in NIDDM patients and, in fact, may reflect a state of generalized vascular damage occurring throughout the body. Prospective studies in NIDDM patients are needed to determine the predictive effect of UAE and the effect of decreasing UAE on future diabetic micro- and macrovascular complications.

Baseline characteristics of participants in the Appropriate Blood Pressure Control in Diabetes trial

The ABCD (Appropriate Blood Pressure Control in Diabetes) trial is a large, prospective, randomized clinical trial designed to compare the effects of intensive with moderate blood pressure control on the prevention and progression of diabetic nephropathy, retinopathy, cardiovascular disease, and neuropathy in non-insulin-dependent diabetes (NIDDM). The secondary objective is to determine equivalency of the effects of a calcium channel blocker (nisoldipine) and of an angiotensin-converting enzyme inhibitor (enalapril) as a first-line antihypertensive agent in the prevention and/or progression of these diabetic vascular complications. The study consists of two study populations: a hypertensive one (diastolic blood pressure of > or = 90.0 mm Hg at the time of randomization) and a normotensive one (diastolic blood pressure of 80.0-89.0 mm Hg at the time of randomization). A total of 950 men and women aged 40-74 years were randomized and are being followed for 5 years at a single center. There were 470 randomized participants in the hypertensive population and 480 randomized participants in the normotensive population. This report summarizes the demographic, biochemical, and clinical characteristics of the randomized patients at the time of entry into the trial and evaluates the balance between the treatment groups within each population.

Effect of risk factors on exercise capacity in NIDDM

Exercise capacity has been used as a noninvasive parameter for predicting cardiovascular events. It is known that diabetic patients have an impaired exercise capacity when compared with nondiabetic age-matched control subjects, but the risk factors associated with this impairment have not been thoroughly analyzed. A total of 453 male and female NIDDM patients who underwent graded exercise testing with expired gas analysis were studied to determine the possible influences of demographic and cardiac risk factors on exercise capacity. Univariate and multiple linear regression analyses were performed on baseline patient characteristics with respect to peak oxygen consumption (VO2). In the regression analyses, African-American race was strongly associated with a decrease in peak VO2; the difference in means between African-Americans and other subjects for men was -2.50 ml.kg-1.min-1 (-4.28, -0.07, 95% CI) (P < 0.006) and for women was -2.96 ml.kg-1.min-1 (-4.45, -1.47) (P < 0.0002). Univariate analyses revealed that African-American subjects had increased prevalence, longer duration, and higher systolic and diastolic hypertension than the non-Hispanic and Hispanic whites. Other independent predictors of peak VO2 (reported as change in peak VO2 in milliliters per kilogram per minute) were BMI (men: -0.39 kg/m2 [-0.52, -0.29], P < 0.0001; women: -0.39 kg/m2 [-0.48, -0.31], P < 0.0001), age (men: -0.16/year [-0.23, -0.09], P < 0.0001; women: -0.17/year [-0.24, -0.11], P < 0.0001), baseline resting systolic blood pressure (men: -0.03/mmHg [-0.06, -0.01], P < 0.05; women: -0.03/mmHg (-0.06, -0.01)f1p4< 0.05), and pack-years smoking (men: -0.04/pack-years [-0.04, -0.01], P < 0.01; women: -0.04/pack-years [-0.07, -0.01], P < 0.0001). Thus, in this large NIDDM study, weight loss, smoking cessation, and aggressive blood pressure control, particularly in African-Americans with NIDDM, would appear to be important in improving exercise capacity and potentially improving the increased cardiovascular mortality associated with an impaired exercise capacity.