A novel blood-based bioassay to monitor adiponectin signaling

The diverse beneficial effects of adiponectin-receptor signaling, including its impact on the regulation of inflammatory processes in vivo, have resulted in development of adiponectin receptor agonists as a treatment for metabolic disorders. However, there are no established non-invasive bioassays for detection of adiponectin target engagement in humans or animal models. Here, we designed an assay using small amounts of blood to assess adiponectin action. Specifically, we tested effects of the small 10-amino acid peptide adiponectin receptor agonist, ALY688, in a sublethal LPS endotoxemia model in mice. LPS-induced pro-inflammatory cytokine levels in serum were significantly reduced in mice treated with ALY688, assessed via multiplex ELISA in flow cytometry. Furthermore, ALY688 alone significantly induced TGF-β release in serum 1 h after treatment and was elevated for up to 24 h. Additionally, using a flow-cytometry panel for detection of changes in circulating immune cell phenotypes, we observed a significant increase in absolute T cell counts in mice after ALY688 treatment. To assess changes in intracellular signaling effectors downstream of adiponectin, phospho-flow cytometry was conducted. There was a significant increase in phosphorylation of AMPK and p38-MAPK in mice after ALY688 treatment. We then used human donor immune cells (PBMCs) treated with ALY688 ex vivo and observed elevation of AMPK and p38-MAPK phosphorylation from baseline in response to ALY688. Together, these results indicate we can detect adiponectin action on immune cells in vivo by assessing adiponectin signaling pathway for AMPK and p38-MAPK, as well as pro-inflammatory cytokine levels. This new approach provides a blood-based bioassay for screening adiponectin action.

The slow-release adiponectin analog ALY688-SR modifies early-stage disease development in the D2.mdx mouse model of Duchenne muscular dystrophy

Fibrosis is associated with respiratory and limb muscle atrophy in Duchenne muscular dystrophy (DMD). Current standard of care partially delays the progression of this myopathy but there remains an unmet need to develop additional therapies. Adiponectin receptor agonism has emerged as a possible therapeutic target to lower inflammation and improve metabolism in mdx mouse models of DMD but the degree to which fibrosis and atrophy are prevented remain unknown. Here, we demonstrate that the recently developed slow-release peptidomimetic adiponectin analog, ALY688-SR, remodels the diaphragm of murine model of DMD on DBA background (D2.mdx) mice treated from days 7-28 of age during early stages of disease. ALY688-SR also lowered interleukin-6 (IL-6) mRNA but increased IL-6 and transforming growth factor-β1 (TGF-β1) protein contents in diaphragm, suggesting dynamic inflammatory remodeling. ALY688-SR alleviated mitochondrial redox stress by decreasing complex I-stimulated H2O2 emission. Treatment also attenuated fibrosis, fiber type-specific atrophy, and in vitro diaphragm force production in diaphragm suggesting a complex relationship between adiponectin receptor activity, muscle remodeling, and force-generating properties during the very early stages of disease progression in murine model of DMD on DBA background (D2.mdx) mice. In tibialis anterior, the modest fibrosis at this young age was not altered by treatment, and atrophy was not apparent at this young age. These results demonstrate that short-term treatment of ALY688-SR in young D2.mdx mice partially prevents fibrosis and fiber type-specific atrophy and lowers force production in the more disease-apparent diaphragm in relation to lower mitochondrial redox stress and heterogeneous responses in certain inflammatory markers. These diverse muscle responses to adiponectin receptor agonism in early stages of DMD serve as a foundation for further mechanistic investigations.NEW & NOTEWORTHY There are limited therapies for the treatment of Duchenne muscular dystrophy. As fibrosis involves an accumulation of collagen that replaces muscle fibers, antifibrotics may help preserve muscle function. We report that the novel adiponectin receptor agonist ALY688-SR prevents fibrosis in the diaphragm of D2.mdx mice with short-term treatment early in disease progression. These responses were related to altered inflammation and mitochondrial functions and serve as a foundation for the development of this class of therapy.

Cardioprotection by the adiponectin receptor agonist ALY688 in a preclinical mouse model of heart failure with reduced ejection fraction (HFrEF)

AIMS

Adiponectin has been shown to mediate cardioprotective effects and levels are typically reduced in patients with cardiometabolic disease. Hence, there has been intense interest in developing adiponectin-based therapeutics. The aim of this translational research study was to examine the functional significance of targeting adiponectin signaling with the adiponectin receptor agonist ALY688 in a mouse model of heart failure with reduced ejection fraction (HFrEF), and the mechanisms of cardiac remodeling leading to cardioprotection.

METHODS AND RESULTS

Wild-type mice were subjected to transverse aortic constriction (TAC) to induce left ventricular pressure overload (PO), or sham surgery, with or without daily subcutaneous ALY688-SR administration. Temporal analysis of cardiac function was conducted via weekly echocardiography for 5 weeks and we observed that ALY688 attenuated the PO-induced dysfunction. ALY688 also reduced cardiac hypertrophic remodeling, assessed via LV mass, heart weight to body weight ratio, cardiomyocyte cross sectional area, ANP and BNP levels. ALY688 also attenuated PO-induced changes in myosin light and heavy chain expression. Collagen content and myofibroblast profile indicated that fibrosis was attenuated by ALY688 with TIMP1 and scleraxis/periostin identified as potential mechanistic contributors. ALY688 reduced PO-induced elevation in circulating cytokines including IL-5, IL-13 and IL-17, and the chemoattractants MCP-1, MIP-1β, MIP-1alpha and MIP-3α. Assessment of myocardial transcript levels indicated that ALY688 suppressed PO-induced elevations in IL-6, TLR-4 and IL-1β, collectively indicating anti-inflammatory effects. Targeted metabolomic profiling indicated that ALY688 increased fatty acid mobilization and oxidation, increased betaine and putrescine plus decreased sphingomyelin and lysophospholipids, a profile indicative of improved insulin sensitivity.

CONCLUSION

These results indicate that the adiponectin mimetic peptide ALY688 reduced PO-induced fibrosis, hypertrophy, inflammation and metabolic dysfunction and represents a promising therapeutic approach for treating HFrEF in a clinical setting.

Association between glomerular filtration rate and plasma N-terminal pro-atrial natriuretic peptide concentration in dogs

OBJECTIVES

To investigate the association between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate in dogs.

MATERIALS AND METHODS

Dogs were classified into four categories by bodyweight. Dogs were divided into four groups (Groups 1 to 4) based on glomerular filtration rate estimates using plasma iohexol clearance per bodyweight category. Generalised linear models were built to explore the relationship between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate and the effect of confounders on plasma N-terminal pro-atrial natriuretic peptide concentration.

RESULTS

Fifty-three dogs were included (Group 1, 25; Group 2, seven; Group 3, five; and Group 4, 16). The medians (interquartile range) N-terminal pro-atrial natriuretic peptide concentrations for Groups 1 to 4 were 7224 pg/mL (4766 to 10,254 mg/dL), 8958 pg/mL (4935 to 11,271 mg/dL), 9280 pg/mL (9195 to 10,384 mg/dL) and 12,683 pg/mL (9133 to 19,217 mg/dL), respectively. Group 4, estimated to have the highest reduction in glomerular filtration rate, had a higher plasma N-terminal pro-atrial natriuretic peptide concentration than Groups 1 to 3. Based on the final generalised linear model, influencing factors for plasma N-terminal pro-atrial natriuretic peptide concentration were plasma iohexol clearance (-0.136; 95% confidence interval, -0.227 to -0.046) and bodyweight (-0.058; 95% confidence interval, -0.098 to -0.018).

CLINICAL SIGNIFICANCE

N-terminal pro-atrial natriuretic peptide concentration is associated with the glomerular filtration rate.

Phase Ⅰ/Ⅱ, Double-Masked, Randomized, Vehicle-Controlled Study of H-1337 Ophthalmic Solution for Glaucoma and Ocular Hypertension

PURPOSE

To perform a phase Ⅰ/Ⅱ evaluation of an H-1337 ophthalmic solution in subjects with primary open-angle glaucoma (POAG) or ocular hypertension (OHT).

DESIGN

This was a phase I/II, randomized, double-masked, vehicle-controlled, dose-response study conducted at 6 private practice sites in the United States. The study was registered with clinicaltrials.gov as NCT03452033.

PARTICIPANTS

Eighty-seven subjects with bilateral POAG or OHT were enrolled.

METHODS

After washout of ocular hypotensive medications as required, the subjects were randomized to receive either the H-1337 ophthalmic solution at 0.06%, 0.2%, and 0.6% or its vehicle twice daily unilaterally in the study eye for the first 3 days and then twice daily in both eyes from day 4 to 28.

MAIN OUTCOME MEASURES

The primary efficacy end point was the mean change in intraocular pressure from baseline (day 0) for each group on day 28 at hour 4 compared with the vehicle.

RESULTS

In the primary efficacy end point, i.e., mean change from the baseline on day 28 at hour 4, the mean change from the baseline was - 4.45 ± 3.801, - 5.16 ± 3.114, - 4.93 ± 3.110, and - 0.39 ± 2.355 in the 0.06%, 0.2%, and 0.6% H-1337 and vehicle groups, respectively. The difference between each active group and the vehicle group was statistically significant (P < 0.0001). Treatment-emergent adverse events (TEAEs) occurred in 49% of subjects who received H-1337 (range, 41% [0.2% arm]-64% [0.6% arm] across the H-1337 arms) and 18% of subjects who received the vehicle. The majority of TEAEs were mild in severity; 3 subjects who received H-1337 had a TEAE of moderate intensity (instillation site erythema, blurred vision, and muscle strain).

CONCLUSIONS

The H-1337 ophthalmic solution showed clinically and statistically significant ocular hypotensive activity and was well tolerated, with a relatively low incidence of hyperemia.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

CSF1 receptor inhibition of tenosynovial giant cell tumor using novel disease-specific MRI measures of tumor burden

Aim: Monitoring treatment of tenosynovial giant cell tumor (TGCT) is complicated by the irregular shape and asymmetrical growth of the tumor. We compared responses to pexidartinib by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 with those by tumor volume score (TVS) and modified RECIST (m-RECIST). Materials & methods: MRIs acquired every two cycles were assessed centrally using RECIST 1.1, m-RECIST and TVS and tissue damage score (TDS). Results: Thirty-one evaluable TGCT patients were treated with pexidartinib. From baseline to last visit, 94% of patients (29/31) showed a decrease in tumor size (median change: -60% [RECIST], -66% [m-RECIST], -79% [TVS]). All methods showed 100% disease control rate. For TDS, improvements were seen in bone erosion (32%), bone marrow edema (58%) and knee effusion (46%). Conclusion: TVS and m-RECIST offer potentially superior alternatives to conventional RECIST for monitoring disease progression and treatment response in TGCT. TDS adds important information about joint damage associated with TGCT.

Results from Phase I Extension Study Assessing Pexidartinib Treatment in Six Cohorts with Solid Tumors including TGCT, and Abnormal CSF1 Transcripts in TGCT

PURPOSE

To assess the response to pexidartinib treatment in six cohorts of adult patients with advanced, incurable solid tumors associated with colony-stimulating factor 1 receptor (CSF1R) and/or KIT proto-oncogene receptor tyrosine kinase activity.

PATIENTS AND METHODS

From this two-part phase I, multicenter study, pexidartinib, a small-molecule tyrosine kinase inhibitor that targets CSF1R, KIT, and FMS-like tyrosine kinase 3 (FLT3), was evaluated in six adult patient cohorts (part 2, extension) with advanced solid tumors associated with dysregulated CSF1R. Adverse events, pharmacokinetics, and tumor responses were assessed for all patients; patients with tenosynovial giant cell tumor (TGCT) were also evaluated for tumor volume score (TVS) and patient-reported outcomes (PRO). CSF1 transcripts and gene expression were explored in TGCT biopsies.

RESULTS

Ninety-one patients were treated: TGCT patients (n = 39) had a median treatment duration of 511 days, while other solid tumor patients (n = 52) had a median treatment duration of 56 days. TGCT patients had response rates of 62% (RECIST 1.1) and 56% (TVS) for the full analysis set. PRO assessments for pain showed improvement in patient symptoms, and 76% (19/25) of TGCT tissue biopsy specimens showed evidence of abnormal CSF1 transcripts. Pexidartinib treatment of TGCT resulted in tumor regression and symptomatic benefit in most patients. Pexidartinib toxicity was manageable over the entire study.

CONCLUSIONS

These results offer insight into outcome patterns in cancers whose biology suggests use of a CSF1R inhibitor. Pexidartinib results in tumor regression in TGCT patients, providing prolonged control with an acceptable safety profile.

Recurrent Mutations in Cyclin D3 Confer Clinical Resistance to FLT3 Inhibitors in Acute Myeloid Leukemia

PURPOSE

Biomarkers of response and resistance to FLT3 tyrosine kinase inhibitors (TKI) are still emerging, and optimal clinical combinations remain unclear. The purpose of this study is to identify co-occurring mutations that influence clinical response to the novel FLT3 inhibitor pexidartinib (PLX3397).

EXPERIMENTAL DESIGN

We performed targeted sequencing of pretreatment blasts from 29 patients with FLT3 internal tandem duplication (ITD) mutations treated on the phase I/II trial of pexidartinib in relapsed/refractory FLT3-ITD+ acute myeloid leukemia (AML). We sequenced 37 samples from 29 patients with available material, including 8 responders and 21 non-responders treated at or above the recommended phase II dose of 3,000 mg.

RESULTS

Consistent with other studies, we identified mutations in NRAS, TP53, IDH2, and a variety of epigenetic and transcriptional regulators only in non-responders. Among the most frequently mutated genes in non-responders was Cyclin D3 (CCND3). A total of 3 individual mutations in CCND3 (Q276*, S264R, and T283A) were identified in 2 of 21 non-responders (one patient had both Q276* and S264R). No CCND3 mutations were found in pexidartinib responders. Expression of the Q276* and T283A mutations in FLT3-ITD MV4;11 cells conferred resistance to apoptosis, decreased cell-cycle arrest, and increased proliferation in the presence of pexidartinib and other FLT3 inhibitors. Inhibition of CDK4/6 activity in CCND3 mutant MV4;11 cells restored pexidartinib-induced cell-cycle arrest but not apoptosis.

CONCLUSIONS

Mutations in CCND3, a gene not commonly mutated in AML, are a novel cause of clinical primary resistance to FLT3 inhibitors in AML and may have sensitivity to CDK4/6 inhibition.

Long-term outcomes of pexidartinib in tenosynovial giant cell tumors

Background

The objective of this study was to report on the long‐term effects of pexidartinib on tenosynovial giant cell tumor (TGCT).

Methods

This was a pooled analysis encompassing 3 pexidartinib‐treated TGCT cohorts: 1) a phase 1 extension study (NCT01004861; 1000 mg/d; n = 39), 2) ENLIVEN patients randomized to pexidartinib (1000 mg/d for 2 weeks and then 800 mg/d; n = 61), and 3) ENLIVEN crossover patients (NCT02371369; 800 mg/d; n = 30). Eligible patients were 18 years old or older and had a histologically confirmed TGCT that was unresectable and symptomatic. Efficacy endpoints included the best overall response (complete or partial response) and the duration of response (DOR) by the Response Evaluation Criteria in Solid Tumors (RECIST) and the tumor volume score (TVS). The safety assessment included the frequency of treatment‐emergent adverse events (TEAEs) and hepatic laboratory abnormalities (aminotransferase elevations and mixed/cholestatic hepatotoxicity). The data cutoff was May 31, 2019.

Results

One hundred thirty patients with TGCT received pexidartinib (median treatment duration, 19 months; range, 1 to 76+ months); 54 (42%) remained on treatment at the end of the analysis (26 months after initial data cut of March 2017). The RECIST overall response rate (ORR) was 60%; the TVS ORR was 65%. The median times to response were 3.4 (RECIST) and 2.8 months (TVS), with 48 of the responding patients (62%) achieving a RECIST partial response by 6 months and with 72 (92%) doing so by 18 months. The median DOR was reached for TVS (46.8 months). Reported TEAEs were mostly low‐grade, with hair color changes being most frequent (75%). Most liver abnormalities (92%) were aminotransferase elevations; 4 patients (3%) experienced mixed/cholestatic hepatotoxicity (all within the first 2 months of treatment), which was reversible in all cases (recovery spanned 1‐7 months).

Conclusions

This study demonstrates the prolonged efficacy and tolerability of long‐term pexidartinib treatment for TGCT.

This analysis further illustrates that systemic therapy targeting the CSF1/CSF1R pathway is an effective therapeutic strategy in patients with tenosynovial giant cell tumor. Because of the limited availability of long‐term prospective data for tenosynovial giant cell tumor, these findings are encouraging and demonstrate the overall long‐term benefit of continued treatment with pexidartinib.

Abstract 2020: Identification of abnormal CSF1 transcripts in tenosynovial giant cell tumors and dose-dependent increase in plasma CSF1 levels in response to pexidartinib treatment

Background: Tenosynovial giant cell tumors (TGCTs) are characterized by rearrangements of the colony-stimulating factor 1 (CSF1) gene. Dysregulated CSF1 may attract CSF1 receptor (CSF1R)-bearing mononuclear cells that form the bulk of the tumor. CSF1R inhibitors including pexidartinib have been developed and have proven to be effective therapies.

Methods: Formalin-fixed paraffin-embedded (FFPE) TGCT specimens from the phase 1 first-in-human study of pexidartinib (NCT01004861) were analyzed using a custom sequencing assay to detect CSF1 genetic alterations. The ArcherDX RNA panel (ArcherDX, Inc., Boulder, CO) consisted of 33 gene-specific primer sets specifically designed to target CSF1, including at least 1 primer set to target each exon/exon boundary as well as primer sets to tile the 3′-untranslated region (3′UTR). Plasma samples from 5 phase 1 trials of pexidartinib across multiple tumor types (NCT02777710, NCT01217229, NCT01525602, NCT01790503, NCT02452424) were assayed for CSF1 protein by solid-phase ELISA (Quantikine® Human MCSF, R&D Systems, Inc., Minneapolis, MN) at baseline and following pexidartinib (200-1200 mg).

Results: FFPE TGCT specimens (N=25) were successfully isolated, prepared into libraries, and sequenced; 8 showed evidence of gene rearrangements at the junction of CSF1 exons 5/6, and 15 showed alterations of the CSF1 3′UTR (n=23). All 25 TGCT libraries had higher CSF1 expression, with 24 exceeding 2-fold of the RNA control library. The plasma samples from 132 patients were analyzed for CSF1 protein. Pexidartinib treatment (200-1200 mg) led to a dose-dependent increase in plasma CSF1 by day 8, 15, or 29. Significant (&gt;4-fold) CSF1 elevation was observed at 600 mg or higher doses.

Discussion: All 25 analyzed TGCT study patients had tumor tissue with elevated CSF1 ligand transcripts, and 23 had CSF1 genomic alterations identified, thus confirming the TGCT etiology for which pexidartinib therapy was recently approved. The initial discovery of gross chromosomal aberrations involving the CSF1 locus used break-apart FISH probes (West et al. Proc Natl Acad Sci USA. 2006;103:690-695). Details of the CSF1 gene aberrations were obtained here using a sequencing assay suitable for FFPE specimens having partially degraded RNA. Abnormal CSF1 transcripts identified in our study are similar to those published by others (Ho et al. Genes Chromosomes Cancer. 2019[Epub]; Tsuda et al. Int J Cancer. 2019;145:3276-3284) after completion of our work, including both predicted fusion proteins and loss of 3′UTR microRNA negative regulatory sites. Increased plasma CSF1 is a useful pharmacodynamics marker of CSF1R inhibition. One potential mechanism for CSF1 plasma elevations could be the inhibition of liver macrophages, known to express CSF1R and thought to play an essential role in the normal clearance of CSF1 from circulation.

Citation Format: Paul Severson, Brian L. West, William D. Tap, Zev A. Wainberg, Sandra Tong-Starksen, Henry H. Hsu, Chao Zhang. Identification of abnormal CSF1 transcripts in tenosynovial giant cell tumors and dose-dependent increase in plasma CSF1 levels in response to pexidartinib treatment [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 2020.

Therapeutic Effect of Topical Adiponectin-Derived Short Peptides Compared with Globular Adiponectin in Experimental Dry Eye and Alkali Burn

Purpose: To evaluate the efficacy of adiponectin (APN)-derived short peptides (ADPs) 355 compared with globular APN in a mouse model of experimental dry eye (EDE) and corneal alkali burn. Methods: EDE and chemical burn were induced in C57BL/6 mice by desiccating stress and application of NaOH, respectively. Eye drops consisting of 0.01% globular APN, 0.01% ADPs, 0.1% ADPs, or balanced salt solution (BSS) were applied. Tear volume, tear film break-up time, and corneal staining scores were measured. Concentrations of interleukin (IL)-1β, interferon (IFN)-γ, IL-6, CXCL-9, and CXCL-10 using multiplex immunobead assay were evaluated, and flow cytometry were performed. Corneal epithelial defects and haze degree were analyzed, and enzyme-linked immunosorbent assay for IL-1β and transforming growth factor (TGF)-β levels were observed. Results: All treatment groups showed an improvement in clinical parameters and CD4+CCR5+ T cell and CD11b+ cell infiltrations in the conjunctiva (all P < 0.05). Both ADPs groups had significantly decreased concentrations of IL-1β, IFN-γ, IL-6, CXCL-9, and CXCL-10 in the conjunctiva than the EDE or BSS group. Significantly improved parameters of epithelial defect, degree of haze, and concentrations of IL-1β and TGF-β were observed in all treatment groups. However, no significant differences were noted in clinical or experimental parameters among treatment groups. Conclusion: Topical ADPs could effectively improve clinical signs and inflammation of ocular surface in the EDE or alkali burn, and its efficacy and potency were similar to those of globular APN.

Low-Voltage Metal-Oxide Thin Film Transistors Using P-Type Tin-Oxide Semiconductors

In this paper, the effect of channel annealing and oxygen flow rate in P-type tin-monoxide (SnO) thin film transistor (TFT) was investigated to reach the process compatibility with n-type oxide-based TFT. The optimized P-type SnO TFT with a small threshold voltage of -0.1 V, a high field-effect mobility of 4 cm² V^-1 s^-1 and an on/off current ratio of >10² was proposed. From the experimental results, the 150 °C channel annealing revealed a metallic behavior but a semiconductor-like property at a higher 200 °C that was favorable for transistor rectification. Besides, the higher oxygen flow rate was also helpful for improving device mobility and driving current, but shows a slight increase in off-state leakage, which is unavoidable due to the increase of grain in SnO channel.

Pexidartinib versus placebo for advanced tenosynovial giant cell tumour (ENLIVEN): a randomised phase 3 trial

BACKGROUND

Tenosynovial giant cell tumour (TGCT), a rare, locally aggressive neoplasm, overexpresses colony-stimulating factor 1 (CSF1). Surgery is standard with no approved systemic therapy. We aimed to evaluate pexidartinib, a CSF1 receptor inhibitor, in patients with TGCT to provide them with a viable systemic treatment option, especially in cases that are not amenable to surgical resection.

METHODS

This phase 3 randomised trial had two parts. Part one was a double-blind study in which patients with symptomatic, advanced TGCT for whom surgery was not recommended were randomly assigned via an integrated web response system (1:1) to the pexidartinib or placebo group. Individuals in the pexidartinib group received a loading dose of 1000 mg pexidartinib per day orally (400 mg morning; 600 mg evening) for the first 2 weeks, followed by 800 mg per day (400 mg twice a day) for 22 weeks. Part two was an open-label study of pexidartinib for all patients. The primary endpoint, assessed in all intention-to-treat patients, was overall response at week 25, and was centrally reviewed by RECIST, version 1.1. Safety was analysed in all patients who received at least one dose of the study drug. This study is registered with ClinicalTrials.gov, number NCT02371369.

FINDINGS

Between May 11, 2015, and Sept 30, 2016, of 174 patients assessed for eligibility, 120 patients were randomly assigned to, and received, pexidartinib (n=61) or placebo (n=59). There were 11 dropouts in the placebo group and nine in the pexidartinib group. Emergence of mixed or cholestatic hepatotoxicity caused the data monitoring committee to stop enrolment six patients short of target. The proportion of patients who achieved overall response was higher for pexidartinib than placebo at week 25 by RECIST (24 [39%] of 61 vs none of 59; absolute difference 39% [95% CI 27-53]; p<0·0001). Serious adverse events occurred in eight (13%) of 61 patients in the pexidartinib group and one (2%) of 59 patients in the placebo group. Hair colour changes (67%), fatigue (54%), aspartate aminotransferase increase (39%), nausea (38%), alanine aminotransferase increase (28%), and dysgeusia (25%) were the most frequent pexidartinib-associated adverse events. Three patients given pexidartinib had aminotransferase elevations three or more times the upper limit of normal with total bilirubin and alkaline phosphatase two or more times the upper limit of normal indicative of mixed or cholestatic hepatotoxicity, one lasting 7 months and confirmed by biopsy.

INTERPRETATION

Pexidartinib is the first systemic therapy to show a robust tumour response in TGCT with improved patient symptoms and functional outcomes; mixed or cholestatic hepatotoxicity is an identified risk. Pexidartinib could be considered as a potential treatment for TGCT associated with severe morbidity or functional limitations in cases not amenable to improvement with surgery.

FUNDING

Daiichi Sankyo.

The measurement of physical functioning among patients with Tenosynovial Giant Cell Tumor (TGCT) using the Patient-Reported Outcomes Measurement Information System (PROMIS)

Background

Tenosynovial giant cell tumor (TGCT), a rare, locally aggressive neoplasm of the synovium of joints and tendon sheaths, is associated with joint destruction, pain and swelling. Impacts on physical function (PF) vary depending on tumor size and location. The aim of this study was to identify relevant items, and demonstrate the content validity of custom measures of lower extremity PF from the Patient-Reported Outcomes Measurement Information System Physical Function Physical Function (PROMIS-PF) item bank among patients with TGCT.

Methods

Patients were recruited for qualitative research interviews to identify predominant TGCT symptoms and impacts. Patients completed a checklist to evaluate the relevance of each PROMIS-PF item. The publicly available PROMIS-PF item response theory (IRT) parameters were used to select items representing the range of the latent PF trait.

Results

Participants (n = 20) were 75% female, mean age 42.5 years. TGCTs were located in the knee (n = 15), hip (n = 3), and ankle (n = 2). Fifty-four PROMIS-PF items were identified as relevant by ≥20% of the participants. PF concepts discussed by participants during the qualitative interviews were also used to select relevant items. Selected items (n = 13) were used to create a physical function subscale specific to lower extremity tumors.

Conclusions

We describe a novel method of combining qualitative research and IRT-based item information to select a relevant and content valid subset of PROMIS-PF items to assess heterogeneous impacts on PF in TGCT, a rare disease population.

Electronic supplementary material

The online version of this article (10.1186/s41687-019-0099-0) contains supplementary material, which is available to authorized users.

Abstract B176: Results of a phase I study of PLX8394, a next-generation BRAF inhibitor, in refractory solid tumors

Background: First-generation BRAF inhibitors (BRAFi) such as vemurafenib and dabrafenib demonstrated high response rates and prolonged survival in some BRAFV600-mutated cancers; however, most patients ultimately develop resistance. Furthermore, treatment-emergent skin and other epithelial malignancies present safety concerns. PLX8394 is a next-generation, orally available, small-molecule BRAFi. Unlike first-generation BRAFi, PLX8394 [a] does not induce paradoxical activation of the RAF/MEK/ERK pathway in cells with stimulated RAS signaling, and [b] blocks signaling from both monomeric BRAFV600 and dimeric BRAFnon-V600 mutations. Thus, we hypothesize that PLX8394 may yield improved safety and broader, more durable efficacy than first-generation BRAFi. Methods: Trial protocol PLX120-03 (NCT02428712) incorporates an open-label, multicenter, phase I study using a 3+3 design to determine the recommended phase II dose (RP2D) in patients with refractory or relapsed solid tumors with or without BRAF mutation. Other endpoints are safety, including dermatologic and ophthalmic adverse events (AEs), pharmacokinetics (PK), and response per RECIST1.1. Dose escalation includes cohorts with either PLX8394 monotherapy or PLX8394 coadministered with an oral CYP3A4 inhibitor, cobicistat 150mg, to enhance systemic PK. Enrollment at the RP2D continues in the subsequent phase II study. Results: Of 26 patients who received at least 1 dose of PLX8394, 15 patients (10 with BRAF mutation) were enrolled to cohorts with PLX8394 monotherapy: 450mg BID (n=8), 900mg BID (n=3), 450mg TID (n=4). PK studies demonstrated lower than expected drug exposures; the protocol was amended and 11 additional patients (8 with BRAF mutation) were enrolled in cohorts with PLX8394 coadministered with cobicistat: 450mg BID (n=5) and 900mg BID (n=6). As of 31 May 2017 cutoff, 15 subjects terminated the study: 14 for disease progression, 1 subject withdrawal. Duration of study drug exposure was a median of 56 (22 - 727) days. Reversible Grade (G) 3 transaminitis in a patient treated with PLX8394 900mg BID + cobicistat was the only dose-limiting toxicity (DLT); rechallenge with PLX8394 alone was tolerated without recurrence of transaminitis. PLX8394 900mg BID + cobicistat was declared as RP2D. Treatment-related G&gt;3 AEs other than DLT included G3 diarrhea (n=1), G3 anorexia (n=1), both in PLX8394 monotherapy cohorts and both manageable with supportive care. There were no cutaneous or ocular AEs. Cobicistat coadministration resulted in a 2-3 fold increase in PLX8394 systemic exposure, with RP2D achieving the projected efficacious exposure range based on preclinical models. There were no objective responses in PLX8394 monotherapy cohorts; however, to date 2 (28%) of 7 evaluable BRAF mutant patients treated with PLX8394 + cobicistat achieved partial responses (BRAFV600E-mutated colorectal cancer, 42% and BRAFV600E-mutated glioma, 65%; both BRAFi naive), which were confirmed by 8-wk serial scans. Tumors without BRAF mutation showed no response. Conclusion: PLX8394 with cobicistat was very well tolerated and showed promising activity in refractory solid tumors with BRAF mutation. A phase II study in BRAF-mutated cancers is ongoing.

Citation Format: Filip Janku, Ulka Vaishampayan, Vivek Khemka, Minny Bhatty, Chao Zhang, Henry H. Hsu, Paul S. Lin, Sandra Tong, Sunil Sharma. Results of a phase I study of PLX8394, a next-generation BRAF inhibitor, in refractory solid tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B176.

Patient-reported Symptoms of Tenosynovial Giant Cell Tumors

Purpose

Tenosynovial giant cell tumor (TGCT), a rare locally aggressive neoplasm of the synovium of joints and tendon sheaths, is associated with joint destruction, inflammation, pain, and swelling, in part due to colony-stimulating factor 1 receptor–bearing macrophages recruited to the tumor by genetic elevation of colony-stimulating factor 1 activity. The most common treatment is surgery, although promising pharmacologic treatments are in development. Patient-reported outcome (PRO) instruments are critical end points in demonstrating the clinical relevance of standard oncologic outcome measures and the overall impact of novel pharmacologic therapies in nonmalignant neoplastic conditions such as TGCT. The content validity of PROs relevant to patients with TGCT has not been formally investigated, and instruments to evaluate such outcomes do not exist for this condition.

Methods

PRO instruments of potential relevance were evaluated by using a literature review and by clinical and PRO experts. Patients with TGCT were recruited through clinical sites and the Internet for participation in qualitative research interviews to identify predominant symptoms and to test the relevance and content validity of several PRO measures. Select PRO measures were included in a Phase I clinical trial, and preliminary results of the PRO end points are reported descriptively.

Findings

Of the 22 subjects who participated in qualitative interviews, 73% were female, and their mean age was 42.5 years (range, 27–56 years). The TGCTs (19 diffuse and 3 localized) were located in the knee (n = 15), hip (n = 3), ankle (n = 2), elbow (n= 1), and forearm (n = 1). The most common symptoms cited were pain (82%), swelling (86%), stiffness (73%), reduced range of motion (64%), and joint instability (64%), which were consistent with clinical expert input and with the content of instruments chosen by PRO experts. The worst pain numeric rating scale, Patient Reported Outcomes Measurement Information System physical functioning items, and the Western Ontario and McMaster Universities Osteoarthritis Index, as well as a worst stiffness numeric rating scale developed for TGCT, were confirmed as meaningful measures of TGCT patient symptoms and were well understood in qualitative interviews. Results from the Phase I trial showed trends of improvement in both pain and stiffness over time.

Implications

This study is the first to gather information directly from patients with TGCT regarding their symptom experiences. Pain, stiffness, and physical functioning are important treatment outcomes in patients with TGCT. We have identified content-valid PRO measures of these concepts, which are included in an ongoing Phase III TGCT clinical trial with pexidartinib (PLX3397) (NCT02371369).

Orally administered colony stimulating factor 1 receptor inhibitor PLX3397 in recurrent glioblastoma: an Ivy Foundation Early Phase Clinical Trials Consortium phase II study

BACKGROUND

The colony stimulating factor 1 receptor (CSF1R) ligands, CSF1 and interleukin-34, and the KIT ligand, stem cell factor, are expressed in glioblastoma (GB). Microglia, macrophages, blood vessels, and tumor cells also express CSF1R, and depletion of the microglia reduces tumor burden and invasive capacity. PLX3397 is an oral, small molecule that selectively inhibits CSF1R and KIT, penetrates the blood-brain barrier in model systems, and represents a novel approach for clinical development.

METHODS

We conducted a phase II study in patients with recurrent GB. The primary endpoint was 6-month progression-free survival (PFS6). Secondary endpoints included overall survival response rate, safety, and plasma/tumor tissue pharmacokinetics. Exploratory endpoints included pharmacodynamic measures of drug effect in blood and tumor tissue.

RESULTS

A total of 37 patients were enrolled, with 13 treated prior to a planned surgical resection (Cohort 1) and 24 treated without surgery (Cohort 2). PLX3397 was given at an oral dose of 1000 mg daily and was well tolerated. The primary efficacy endpoint of PFS6 was only 8.6%, with no objective responses. Pharmacokinetic endpoints revealed a median maximal concentration (Cmax) of 8090 ng/mL, with a time to attain Cmax of 2 hour in plasma. Tumor tissue obtained after 7 days of drug exposure revealed a median drug level of 5500 ng/g. Pharmacodynamic changes included an increase in colony stimulating factor 1 and reduced CD14(dim)/CD16+ monocytes in plasma compared with pretreatment baseline values.

CONCLUSION

PLX3397 was well tolerated and readily crossed the blood-tumor barrier but showed no efficacy. Additional studies are ongoing, testing combination strategies and potential biomarkers to identify patients with greater likelihood of response.

Structure-Guided Blockade of CSF1R Kinase in Tenosynovial Giant-Cell Tumor

BACKGROUND

Expression of the colony-stimulating factor 1 (CSF1) gene is elevated in most tenosynovial giant-cell tumors. This observation has led to the discovery and clinical development of therapy targeting the CSF1 receptor (CSF1R).

METHODS

Using x-ray co-crystallography to guide our drug-discovery research, we generated a potent, selective CSF1R inhibitor, PLX3397, that traps the kinase in the autoinhibited conformation. We then conducted a multicenter, phase 1 trial in two parts to analyze this compound. In the first part, we evaluated escalations in the dose of PLX3397 that was administered orally in patients with solid tumors (dose-escalation study). In the second part, we evaluated PLX3397 at the chosen phase 2 dose in an extension cohort of patients with tenosynovial giant-cell tumors (extension study). Pharmacokinetic and tumor responses in the enrolled patients were assessed, and CSF1 in situ hybridization was performed to confirm the mechanism of action of PLX3397 and that the pattern of CSF1 expression was consistent with the pathological features of tenosynovial giant-cell tumor.

RESULTS

A total of 41 patients were enrolled in the dose-escalation study, and an additional 23 patients were enrolled in the extension study. The chosen phase 2 dose of PLX3397 was 1000 mg per day. In the extension study, 12 patients with tenosynovial giant-cell tumors had a partial response and 7 patients had stable disease. Responses usually occurred within the first 4 months of treatment, and the median duration of response exceeded 8 months. The most common adverse events included fatigue, change in hair color, nausea, dysgeusia, and periorbital edema; adverse events rarely led to discontinuation of treatment.

CONCLUSIONS

Treatment of tenosynovial giant-cell tumors with PLX3397 resulted in a prolonged regression in tumor volume in most patients. (Funded by Plexxikon; ClinicalTrials.gov number, NCT01004861.).

The Role of Oxygen Vacancies on Switching Characteristics of TiO(x) Resistive Memories

Using oxygen vacancy rich (VO-rich) TiO(x) dielectric with high work function Ni electrode, large resistance window of > 10x and narrow current distribution were realized in the Ni/VO-rich TiO(x)/TaN resistive random access memory (RRAM) device. It can be ascribed to the formation and rupture of conducting filaments by the percolation of VOs and Ti interstitials. Moreover, the effects of annealing treatment and top electrode on resistive switching properties were investigated. The device with VO-deficient TiO(x) after annealing reduces the defects and exhibits small window and low switching currents. The device with low work function Ti top electrode provides low barrier to increase reset currents and the randomly distributed filamentary paths forms near the Ti causes wide current distribution.

Characterizing and Overriding the Structural Mechanism of the Quizartinib-Resistant FLT3 "Gatekeeper" F691L Mutation with PLX3397

Tyrosine kinase domain mutations are a common cause of acquired clinical resistance to tyrosine kinase inhibitors (TKI) used to treat cancer, including the FLT3 inhibitor quizartinib. Mutation of kinase "gatekeeper" residues, which control access to an allosteric pocket adjacent to the ATP-binding site, has been frequently implicated in TKI resistance. The molecular underpinnings of gatekeeper mutation-mediated resistance are incompletely understood. We report the first cocrystal structure of FLT3 with the TKI quizartinib, which demonstrates that quizartinib binding relies on essential edge-to-face aromatic interactions with the gatekeeper F691 residue, and F830 within the highly conserved Asp-Phe-Gly motif in the activation loop. This reliance makes quizartinib critically vulnerable to gatekeeper and activation loop substitutions while minimizing the impact of mutations elsewhere. Moreover, we identify PLX3397, a novel FLT3 inhibitor that retains activity against the F691L mutant due to a binding mode that depends less vitally on specific interactions with the gatekeeper position.

SIGNIFICANCE

We report the first cocrystal structure of FLT3 with a kinase inhibitor, elucidating the structural mechanism of resistance due to the gatekeeper F691L mutation. PLX3397 is a novel FLT3 inhibitor with in vitro activity against this mutation but is vulnerable to kinase domain mutations in the FLT3 activation loop.

Low-Voltage InGaZnO Thin Film Transistors with Small Sub-Threshold Swing

We demonstrate a low-voltage driven, indium-gallium-zinc oxide thin-film transistor using high-κ LaAlO3 gate dielectric. A low VT of 0.42 V, very small sub-threshold swing of 68 mV/dec, field-effect mobility of 4.1 cm2/Ns and low operation voltage of 1.4 V were reached simultaneously in LaAlO3/IGZO TFT device. This low-power and small SS TFT has the potential for fast switching speed and low power applications.

The first record, tagging and release of a neonatal whale shark Rhincodon typus in Taiwan

On 27 October 2013, a Rhincodon typus was apparently chased by a group of Caranx ignobilis into nearshore waters near Green Island (Ludao), east of Taiwan. A fisherman brought it back to port where it was kept in a small sea pen until release. The R. typus was 78 cm total length, and was tagged and released on 29 October 2013.

Rational scale-up of a baculovirus-insect cell batch process based on medium nutritional depth

We have developed a serum-free cell culture process utilizing a recombinant baculovirus (AcNPV) expression vector to infect Trichoplusia ni insect cells for the production of the human lysosomal enzyme, glucocerebrosidase. The enzyme, which is harvested as a secreted protein in this process, can serve as a replacement therapy for the genetic deficiency Gaucher disease. In the course of pilot scale-up of a batch glucocerebrosidase process from 25-mL working volume shaker flask units to 25-L working volume stirred bioreactor units, a semi-empirical model was developed for the rational determination of scaleable process parameters, including host cell density at infection, multiplicity of infection (MOI), and harvest time. A key assumption of the model is that maximum protein production is limited by the serum-free medium's nutritional capacity, which can, in turn, be determined from the growth of uninfected cells. For the host cell/medium combination used in this study, the nutritional limit was determined to be 1.3 x 10(7) to 1.7 x 10(7) viable-cell-days/mL. Based on this, the model predicts that optimal protein expression is consistent with a 4-day batch process where the host cell density at the time of infection is 1.5 x 10(6) to 2.0 x 10(6) cells/mL and the MOI is 0.09-0.3. These parameters were empirically confirmed to give the highest achievable batch product yield, first in shaker flasks and then at larger scales. The low MOI allows at least one population doubling to take place post viral addition, so that the effective infected cell density producing product generally exceeds 4 x 10(6) cells/mL. It was also interesting to note that this process consistently achieved the same level of maximum protein production at the 25-L bioreactor scale in 4 days compared to 5 days at the shaker flask scale. This may be attributable to better control of the culture environment in the bioreactor. Unlike some other lepidopteran insect cells, such as Sf-9, T. ni cells were found to produce significant levels of the inhibitory metabolites ammonia and lactate. Our results suggest that reduction and/or removal of inhibitory metabolites might be beneficial for infection of high-density cultures of these cells and might also facilitate application of more sophisticated culture strategies, including fed-batch. (c) 1996 John Wiley & Sons, Inc.

Incremental backpropagation learning networks

How to learn new knowledge without forgetting old knowledge is a key issue in designing an incremental-learning neural network. In this paper, we present a new incremental learning method for pattern recognition, called the "incremental backpropagation learning network", which employs bounded weight modification and structural adaptation learning rules and applies initial knowledge to constrain the learning process. The viability of this approach is demonstrated for classification problems including the iris and the promoter domains.

Fisheries, management and conservation of the whale shark Rhincodon typus in Taiwan

The Taiwanese government introduced a catch-and-report system for the whale shark Rhincodon typus in 2001, and in the following year limited the total allowable catch (TAC) to 80 individuals. This limit was reduced over the following years, reaching a low of 30 individuals in 2007. In November 2007, a comprehensive ban on R. typus fishing came into effect and protection measures were adopted for the species. This study measured and recorded the total length (L(T) ), body mass and sex of 810 R. typus, using fisheries and other released data for the period 1995-2008. The mean L(T) of individuals caught from June to October was smaller than that for individuals caught from November to May. Mean annual catches in set nets were higher in south-western Taiwan than in other regions of Taiwan. The sex ratio showed that males were caught more frequently than females in Taiwanese waters, indicating sex segregation. For the first time, the stock structure, conservation and management regulation of R. typus in the north-west Pacific Ocean have been reviewed. The results provide a useful resource for future assessment of the possible development of R. typus ecotourism in Taiwan.

Topical mecamylamine for diabetic macular edema

PURPOSE

Stimulation of nicotinic acetylcholine (nACh) receptors on vascular endothelial cells promotes angiogenesis and vascular permeability in animal models. The safety and bioactivity of topical mecamylamine, an antagonist of nACh receptors, was tested in patients with diabetic macular edema.

DESIGN

A multicenter phase I/II clinical trial.

METHODS

Twenty-three patients with chronic diabetic macular edema received 1% mecamylamine topically twice daily for 12 weeks, the primary end point. Patients underwent safety assessments, measurement of best-corrected visual acuity (BCVA), and measurement of foveal thickness using optical coherence tomography at baseline, 1, 4, 8, 12, and 16 weeks.

RESULTS

Mecamylamine drops were well tolerated and there were no drug-related safety problems. Mean improvement in BCVA at 1, 4, 8, 12, and 16 weeks was 2.8, 1.9, 2.4, 0.8, and 3.1 letters, respectively. There was little change in mean excess foveal thickness. There was substantial heterogeneity in response, because 8 patients showed convincing improvement in BCVA, foveal thickness, or both, 9 patients showed equivocal or no substantial changes, and 4 patients showed worsening. Five patients showed a substantial improvement in BCVA, foveal thickness, or both between their last visit while receiving mecamylamine and 1 month after stopping mecamylamine.

CONCLUSIONS

This study suggested that administration of topical mecamylamine, a nonspecific nACh receptor blocker, may have heterogeneous effects in patients with diabetic macular edema. Variable expression of nACh receptor subtypes on endothelial cells that have different effects on permeability would provide an explanation for these results and should be investigated, because more specific nACh receptor blockers may dissociate antipermeability and propermeability effects.

A large chest wall tumour in an asymptomatic 15-year-old girl

A 15-year-old asymptomatic girl was found to have a large left lower chest wall mass associated with chest wall invasion on an opportunistic chest radiograph. The tumour was excised and shown to be a clear cell sarcoma. Adjuvant chemotherapy was administered and she was disease free at her 10 month follow up.

Randomized study of adding inhaled iloprost to existing bosentan in pulmonary arterial hypertension

RATIONALE

Small, open-label studies suggest that combinations of existing therapies may be effective for pulmonary arterial hypertension (PAH).

OBJECTIVE

To evaluate the safety and efficacy of adding inhaled iloprost, a prostacyclin analog, to the endothelin receptor antagonist bosentan in patients with PAH.

METHODS

In a randomized, multicenter, double-blind trial, inhaled iloprost (5 mug) or placebo was added to stable monotherapy with bosentan for 12 wk. Efficacy endpoints included change from baseline in 6-min-walk distance (6-MWD), modified New York Heart Association (NYHA) functional class, hemodynamic parameters, and time to clinical worsening.

MEASUREMENTS AND MAIN RESULTS

A total of 67 patients with PAH (55% idiopathic PAH, 45% associated PAH, 94% NYHA class III, and mean baseline 6-MWD of 335 m) were randomized. At Week 12, patients receiving iloprost had a mean increase in 6-MWD of 30 m (p = 0.001); placebo patients had a mean 6-MWD increase of 4 m (p = 0.69), with a placebo-adjusted difference of +26 m (p = 0.051). NYHA status improved by one class in 34% of iloprost versus 6% of placebo patients (p = 0.002). Iloprost delayed the time to clinical worsening (p = 0.0219). Improvements were noted in postinhalation placebo-adjusted change in mean pulmonary artery pressure (-8 mm Hg; p < 0.001) and pulmonary vascular resistance (-254 dyn x s x cm(-5); p < 0.001). Combination therapy was well tolerated.

CONCLUSIONS

Within the limitations of a relatively small sample size, results of this study demonstrate that the addition of inhaled iloprost in patients with PAH with reduced exercise capacity on bosentan monotherapy is safe and efficacious.

Iloprost inhalation solution for the treatment of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a condition that is characterised by increased pulmonary arterial pressure and vascular resistance that can lead to right ventricular failure and death. A variety of disturbances in pulmonary vascular endothelial and smooth muscle function are present in PAH, including reduced production of vasodilator and antiproliferative substances, such as nitric oxide and prostacyclin, and an overproduction of mitogens, such as endothelin. As a result of these observations, therapies have been developed for PAH that specifically target these pathogenic processes, including prostacyclin analogues and endothelin receptor antagonists. This article reviews iloprost inhalation solution, the most recently approved form of prostacyclin therapy that is delivered directly to the lungs by inhalation.

Pilot study of interferon gamma for chronic hepatitis C

BACKGROUND/AIMS

Currently, there are no effective therapies available for patients with chronic hepatitis C who have failed to respond to optimal interferon alfa-based regimens. The aims of this pilot study were to assess the antiviral activity and safety of interferon gamma in chronic hepatitis C.

METHODS

Patients with chronic hepatitis C, genotype 1, who had not responded to or who had relapsed after therapy with interferon alfa and ribavirin were enrolled in a trial of interferon gamma 1b given in doses of 100, 200 or 400 microg subcutaneously three times weekly for 4 weeks. Frequent blood samples were obtained for HCV RNA levels.

RESULTS

Fourteen patients were enrolled. Geometric mean HCV RNA levels remained unchanged. Serum aminotransferase levels also did not change, while there were significant decreases in neutrophil counts (-41% from baseline) and hematocrit (-5%). Low grade fever and malaise were common with the first injection of interferon gamma, but no serious side effects were encountered.

CONCLUSIONS

Although relatively well tolerated, interferon gamma in doses of 100-400 microg thrice weekly had no effect on HCV RNA levels in patients with chronic hepatitis C who had failed to achieve a sustained response to interferon alfa-based therapies.

Solitary fibrous tumors of the pleura: clinical, radiological, surgical and pathological evaluation

AIMS

To report a clinicopathological series of cases of solitary fibrous tumor of the pleura from Taiwan.

METHODS

Clinical data was collected from a review of medical records and telephone interviewing for follow-up.

RESULTS

Eight patients, three men and five women aging from 34 to 71 years, underwent tumor resection and were followed in a period from 7 months to 13.5 years. Six patients underwent standard thoracotomy and two had VATS for tumor excision. Tumors were pathologically benign in seven patients and malignant in one. Patients were all alive with no evidence of tumor recurrence at the time of this report.

CONCLUSIONS

One should always consider SFTPs as potentially malignant tumors. Complete resection remains the mainstay of cure. Standard thoracotomy should always be considered when a high suspicion of malignancy is raised, whereas VATS may be a preferred approach for smaller tumors.

Effects of Anoectochilus formosanus Hayata extract and glucocorticoid on lung maturation in preterm rats

We investigated the effects of maternal administration of Anoectochilus formosanus extract and dexamethasone on lung maturation in preterm rats. A. formosanus group mothers were tube-fed A. formosanus extract (300 mg/kg body wt./day) for 7 days from days 12-18 of gestation. Dexamethasone group mothers were injected intraperitoneally with dexamethasone (0.2 mg/kg body wt.) in saline on day 18 of gestation. Control group mothers were similarly injected with saline alone. On day 19 of gestation, fetuses were delivered by cesarean section. A. formosanus treatment significantly increased the fetal lung/body weight ratio, as compared to dexamethasone treatment. Saturated phosphatidylcholine levels in fetal lung tissue and growth hormone levels in maternal serum were significantly increased in the A. formosanus- and dexamethasone-treated groups as compared to controls. The histological appearance of preterm rat lungs revealed extensive branching of intermediate airways, denser mesenchyme, and more epithelial tubules in the dexamethasone and A. formosanus groups as compared with the control group. These results suggest that antenatal A. formosanus treatment may play a role in accelerating fetal rat lung maturation.

Recombinant Interferon‐γ1b as Adjunctive Therapy for AIDS‐Related Acute Cryptococcal Meningitis

We conducted a phase 2, double-blind, placebo-controlled study to evaluate the safety and antifungal activity of adjuvant recombinant interferon (rIFN)- gamma 1b in patients with acquired immunodeficiency syndrome and acute cryptococcal meningitis. Patients received 100 or 200 microg of rIFN- gamma 1b or placebo, thrice weekly for 10 weeks, plus standard therapy with intravenous amphotericin B, with or without flucytosine, followed by therapy with fluconazole. End points included conversion of cerebrospinal fluid fungal cultures from positive to negative at 2 weeks, resolution of symptoms, and survival. Among 75 patients, 2-week culture conversion occurred in 13% of placebo recipients, 36% of rIFN- gamma 1b (100 microg) recipients, and 32% of rIFN- gamma 1b (200 microg) recipients. There was a trend toward improved combined mycologic and clinical success in rIFN- gamma 1b recipients (26% vs. 8%; P=.078). Therapy with rIFN- gamma 1b was well tolerated, and there was no apparent influence on serial CD4 cell counts and human immunodeficiency virus load measurements. Adjunctive therapy with rIFN- gamma 1b holds promise for patients with acute cryptococcal meningitis and warrants further study.

Imaging findings of intradiaphragmatic bronchogenic cyst: a case report

Isolated intradiaphragmatic bronchogenic cysts are extremely rare. Here, we report a case of intradiaphragmatic bronchogenic cyst with calcifications in a 34-year-old man presenting with no clinical symptoms. Imaging studies of the chest, including chest roentgenogram and computerized tomography (CT), revealed a left posterior mediastinal mass that abutted onto the left diaphragmatic crus with multiple calcifications and showed no enhancement after contrast administration on CT. The patient underwent surgical resection of the mass. Intradiaphragmatic bronchogenic cyst with calcifications was diagnosed by pathology. The patient was discharged 10 days after the operation, and no complication was found 3 months later at follow-up.

An enormous abdominal mass associated with acute renal failure

We report a 67-year-old man with acute uric acid nephropathy, secondary to spontaneous tumor lysis syndrome, that presented itself as a huge intra-abdominal tumor that led to acute renal failure, hyperuricemia, and azotemia. Initial finding of hydronephrosis detected by ultrasonography led us to believe that the azotemia and decreasing amount of urine resulted from obstructive uropathy, a common complication of malignancy, caused by either a direct renal invasion or a urinary outflow tract compression because of a tumor mass effect. However, clinical observations and the response to therapeutic intervention confirmed the diagnosis of spontaneous tumor lysis syndrome, which is a rare cause of acute uric acid nephropathy.

Photon radiation dose enhancement at material interfaces

Experimental radiation dose-effect studies at a material's interface require high-resolution dose measurements resulting from the exposure of mounted samples on a supporting substrate. Reflections of photons and electrons from the substrate increase the effective dose to the sample relative to dose from the direct beam incident on the unbacked sample. This difficult-to-measure enhancement of effective dose can be calculated easily with Monte Carlo transport codes. We have used the Monte Carlo code, CYLTRAN, to carry out radiation transport and dose calculations in very thin water layers backed by different substrate materials. We present cases with an incident photon beam (15-100 keV) on a water medium with five different substrates--mylar, aluminum, copper, silver, and gold.

Diffuse leiomyomatosis of the esophagus

BACKGROUND

Leiomyomas are rare esophagus neoplasms. They are usually solitary, and the diffuse lesion is extremely rare.

CASE REPORT

A 19-year-old male presented with a 3-year history of occasional dysphagia and postprandial regurgitation. The chest radiographs showed a huge mass in the posterior mediastinum. Barium esophagograms showed narrowing of the middle third esophagus with proximal dilatation. The fibroesophagoscopy demonstrated multiple submucosal nodules below a level 22 cm from the incisor and covered with intact mucosa. CT scans of the chest showed a long segment of circumferential soft tissue in the posterior mediastinum which encircled and involved the upper two thirds of the esophagus. An intrathoracic esophagectomy with cervical esophagogastrostomy via the substernal route was performed. Grossly, multiple confluent myomatous nodules circumferentially involved the upper and middle third of the esophagus. Histologic findings showed diffuse leiomyomatosis of the esophagus.

CONCLUSION

Esophageal leiomyomatosis should be considered in a young patient with long-standing dysphagia in whom smooth, tapered esophageal narrowing on barium study and circumferential esophageal wall thickening on CT scan are seen. An esophagectomy combined with a reconstruction procedure is indicated.

Outcomes and APACHE II predictions for critically ill patients with acute renal failure requiring dialysis

BACKGROUND

Despite the widespread availability of dialytic and intensive care unit technology, the probability of early mortality in critically ill patients with acute renal failure (ARF) is still high, and the evaluation of the patients' prognosis has been difficult. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is a reliable indicator of severity of illness and likelihood of survival in critically ill patients with ARF. We have attempted to determine whether the APACHE II scoring system can be used to predict prognosis.

METHODS

A retrospective cohort study evaluated the medical records of 100 consecutive patients in intensive care units with acute renal failure who required dialysis from January 1997 through December 1998.

RESULTS

Of the 100 patients studied, 65 were men and 35 were women. The mean age of survivors and nonsurvivors was 59.4 +/- 20.3 years and 58.3 +/- 20.0 years. The overall mortality rate was 71%. There were no significant differences between survivors and nonsurvivors in age, gender, or indication for dialysis. The cause of death in the majority of patients was related to higher APACHE II score during the 24 hours immediately preceding the initiation of acute hemodialysis, and carry mortality rates exceeding 85% with an APACHE II score of 24 or higher.

CONCLUSION

We conclude that mortality rate for acute renal failure in intensive care unit patients continues to be high. The use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival. There is a significant trend with APACHE II score for outcome.

Isolation of calcifiable vesicles from aortas of rabbits fed with high cholesterol diets

Advanced arterial wall calcification in atherosclerosis imposes a serious rupturing effect on the aorta. However, the mechanism of dystrophic calcification linked to hyperlipidemia, that causes atherosclerosis remains unknown. Emerging morphological and biochemical evidence reveals that calcifiable vesicles may have a role in plaque calcification. To determine whether a high cholesterol diet can induce arterial calcification and produce or activate calcifiable vesicles in aortas, a rabbit model was used. After 2 months of daily high lipid feeding (supplemented with 2% cholesterol and 6% peanut oil), typical atherosclerotic lesions developed. However, the mineral, if present in aortas, was insufficient to be detected by Fourier transform-infrared spectroscopy (FT-IR) or alizarin red staining, indicative of a non-calcifying stage of atherosclerosis. Small segments of thoracic aortas were digested in a crude collagenase solution to release calcifiable vesicles. Vesicles were also isolated from normal aortas as control to consider the possibility that membrane vesicles may be produced by crude collagenase digestion, which could cause the degradation of some cells. Calcifiable vesicles were precipitated at 300,000 x g after subcellular particles were removed by centrifugation at 30,000 x g. Calcifiability of isolated vesicles was then tested using calcifying media containing physiological levels of Ca2+ and Pi and 1 mM ATP. Electron microscopic observations showed that the isolated vesicles were heterogeneous in size and shape and capable of depositing electron dense particles. Fourier transform infrared spectroscopic analysis of the deposited particles revealed the presence of an amorphous mineral phase. The spectroscopic mineral to matrix ratios, related to the amount of mineralization, indicated that vesicles from cholesterol-fed rabbits produced more minerals than control vesicles obtained from the normal aortas. Alizarin red staining for mineral further demonstrated substantially higher calcifiability of the experimental vesicles. A 3-5 h exposure of the vesicles to calcifying media caused significant deposition of 45Ca and 32Pi in a vesicle protein-concentration dependent manner. Similar to previously reported observations with human atherosclerotic aorta vesicles, rabbit vesicles were enriched in ATP-hydrolyzing enzymes including Mg2+- or Ca2+-ATPase and NTP pyrophosphohydrolase that are implicated in normal and pathological calcification. Altogether, these observations suggest that accumulation of the released calcifiable vesicles, as a result of high cholesterol diets, may have a role in dystrophic calcification in hyperlipidemia-related atherosclerosis.

Unicentric Castleman's disease associated with hydronephrosis

We describe a patient with an unusual case of unicentric Castleman's disease, which bore a malignant appearance and was located in the pararenal space. She initially presented with hydronephrosis. Two years after surgical removal of the tumor, no recurrence was evident. To our knowledge, only 2 additional cases of this uncommon disease entity associated with hydronephrosis have been reported. Furthermore, our patient was the first to receive conservative surgery. On the basis of our experience, owing to the benign clinical course of this tumor and its excellent response to limited resection, radical surgery may be avoided.

Safety and immunogenicity of adjuvanted and unadjuvanted subunit influenza vaccines administered intranasally to healthy adults

Antigen-specific mucosal immunity is thought to be important for protection against influenza virus infection. Currently licensed parenteral influenza vaccines stimulate the production of serum antibodies, but are poor inducers of mucosal immunity. The adjuvant MF59 has been shown to enhance the humoral immune response to parenteral influenza vaccine in humans and the mucosal immune response to intranasally-administered influenza vaccine in mice. We conducted an open-label safety study followed by an observer-blind, randomized trial comparing the immune response to intranasally-administered subunit influenza vaccine adjuvanted with MF59, unadjuvanted subunit influenza vaccine, and placebo. Adverse reactions did not occur significantly more frequently in vaccinees than placebo recipients. Of 31 subjects receiving 2 doses of MF59-adjuvanted influenza vaccine, 19 (61%), 8 (26%), and 11 (35%) developed a mucosal IgA response to influenza A/H1N1, A/H3N2, and B, respectively. The percentage of subjects with a serum antibody response was slightly lower. The immune responses to adjuvanted vaccine were not significantly different from those to unadjuvanted vaccine. Both vaccines gave more frequent responses than seen in placebo recipients, indicating the potential of intranasal inactivated vaccines to stimulate local IgA responses.

Thymus size and its relationship to perinatal events

A retrospective study was conducted to assess radiographically the thymus size in well and sick neonates and to search for a possible relationship to perinatal events. Thymus size was expressed as cardiothymic:thoracic ratio (CT/T) by measuring the width of the cardiothymic shadow at the level of carina and dividing it by the width of the thorax at the costophrenic angles. The CT/T was measured on chest radiographs obtained on day 1 in well term neonates consecutively born in our nursery and sick neonates with meconium staining of the amniotic fluid, meconium aspiration syndrome or respiratory distress syndrome (RDS). Neonates with congenital anomalies, congenital heart disease or intrauterine growth retardation were excluded. There were no significant relationships between CT/T and sex, birth route, birthweight or gestational age in well and sick term neonates. The CT/T were comparable among well and sick term neonates and were significantly greater in the preterm neonates with RDS than in the preterm neonates without RDS. The CT/T was correlated to the birth route only in the preterm neonates. We conclude that thymus involution in the perinatal period is a complex process and the response is different between term and preterm neonates.

WENDI: an improved neutron rem meter

Neutron rem meters are routinely used for real-time field measurements of neutron dose equivalent where neutron spectra are unknown or poorly characterized. These meters are designed so that their response per unit fluence approximates an appropriate fluence-to-dose conversion function. Typically, a polyethylene moderator assembly surrounds a thermal neutron detector, such as a BF3 counter tube. Internal absorbers may also be used to further fine-tune the detector response to the shape of the desired fluence conversion function. Historical designs suffer from a number of limitations. Accuracy for some designs is poor at intermediate energies (50 keV-250 keV) critical for nuclear power plant dosimetry. The well-known Andersson-Braun design suffers from angular dependence because of its lack of spherical symmetry. Furthermore, all models using a pure polyethylene moderator have no useful high-energy response, which makes them inaccurate around high-energy accelerator facilities. This paper describes two new neutron rem meter designs with improved accuracy over the energy range from thermal to 5 GeV. The Wide Energy Neutron Detection Instrument (WENDI) makes use of both neutron generation and absorption to contour the detector response function. Tungsten or tungsten carbide (WC) powder is added to a polyethylene moderator with the expressed purpose of generating spallation neutrons in tungsten nuclei and thus enhance the high-energy response of the meter beyond 8 MeV. Tungsten's absorption resonance structure below several keV was also found to be useful in contouring the meter's response function. The WENDI rem meters were designed and optimized using the Los Alamos Monte Carlo codes MCNP, MCNPX, and LAHET. A first generation prototype (WENDI-I) was built in 1995 and its testing was completed in 1996. This design placed a BF3 counter in the center of a spherical moderator assembly, whose outer shell consisted of 30% by weight WC in a matrix of polyethylene. A borated silicone rubber (5% boron by weight) absorber covered an inner polyethylene sphere to control the meter's response at intermediate energies. A second generation design (WENDI-II) was finalized and tested in 1999. It further extended the high-energy response beyond 20 MeV, increased sensitivity, and greatly facilitated the manufacturing process. A 3He counter tube is located in the center of a cylindrical polyethylene moderator assembly. Tungsten powder surrounds the counter tube at an inner radius of 4 cm and performs the double duty of neutron generation above 8 MeV and absorption below several keV. WENDI-II is suitable for field use as a portable rem meter in a variety of work place environments, and has been recently commercialized under license by Eberline Instruments, Inc. and Ludlum Measurements, Inc. Sensitivity is about a factor of 12 higher than that of the Hankins Modified Sphere (Eberline NRD meter) in a bare 252Cf field. Additionally, the energy response for WENDI-II closely follows the contour of the Ambient Dose Equivalent per unit fluence function [H'(10)/phi] above 0.1 MeV. Its energy response at 500 MeV is approximately 15 times higher than that of the Hankins and Andersson-Braun meters. Measurements of the energy and directional response of the improved meter are presented and the measured response function is shown to agree closely with the predictions of the Monte Carlo simulations in the range from 0.144 MeV to 19 MeV.

Effects of lectins on calcification by vesicles isolated from aortas of cholesterol-fed rabbits

Advanced vascular calcification in atherosclerosis weakens arterial walls, thereby imposing a serious rupturing effect. However, the mechanism of dystrophic calcification remains unknown. Although accumulating morphological and biochemical evidence reveals a role for calcifiable vesicles in plaque calcification, the mechanism of vesicle-mediated calcification has not been fully explored. To study whether vesicles' membrane components, such as carbohydrates, may have a role in vesicle-mediated calcification, the effect of sugar-binding lectins on calcification was investigated. Atherosclerosis was developed by feeding rabbits with a diet supplemented with 0.5% cholesterol and 2% peanut oil for 4 months. Calcifiable vesicles were then isolated from thoracic aortas by collagenase digestion. The histological examination of aortas with hematoxylin counter-staining indicated abnormal formation of large plaques enriched with macrophage-derived foam cells. Fourier transform spectroscopy revealed mild calcification in aortas indicating that advanced stages of heavy calcification have yet to be reached. However, vesicles isolated from the aortas were capable of calcification in the presence of physiological levels of Ca(2+), Pi, and ATP. Thus, at this stage of atherosclerosis, aortas may start to produce calcifiable vesicles, but at a level insufficient for substantial formation of mineral in aortas. The assessments by FT-IR analysis and Alizarin red staining indicated that concanavalin A (Con A) substantially increased mineral formation by isolated vesicles. Con A also exerted a marked stimulatory effect on (45)Ca and (32)Pi deposition in a dose-dependent fashion with a half-maximal effect at 6-10 microg/ml. Either alpha-methylmannoside or alpha-methylglucoside, but not mannitol, at 10 mM abolished the stimulation. Con A stimulation was abolished after Con A was removed from calcifying media, suggesting that covalent binding may not be involved in the effect. Galactosides appear to also be implicated in (45)Ca and (32)Pi deposition since Abrus precartorius agglutinin, which specifically binds galactosides, enhanced the deposition. Neither wheat-germ agglutinin that binds N-acetylglucoside nor N-acetylgalactoside-specific Helix pomatia agglutinin was effective, suggesting that the acetylated forms of carbohydrate moieties are either absent in vesicles or may not be involved in calcification. None of these lectins exerted an effect on ATPase. Thus, the effects of lectins appeared to be mediated through interactions with carbohydrate moieties of calcifiable vesicles. Whether stimulation of vesicle-calcification by lectins is of pathological significance in atherosclerotic calcification requires further investigation.

Perspectives for a vaccine against hepatitis C virus

There is no vaccine for HCV and the only available treatment, IFNalpha alone or in combination with ribavirin, has proven efficacious in less than 50% of patients. Given that approximately 200 million chronic HCV infections have been estimated worldwide, there is a pressing need to develop vaccination strategies aimed at preventing and possibly eradicating HCV infection. However, several major practical and scientific problems arise in designing an HCV vaccine. First, HCV is only readily detected as RNA by PCR. Second, the only species that can be infected by HCV are humans and chimpanzees. Third, the virus does not replicate efficiently in vitro. Fourth, some viral proteins have very high mutability. Last, there is little information on correlates of immunity. Although an ideal vaccine should protect from infection, in that it should elicit sterilizing immunity, this is quite an ambitious goal in the PCR era. In the case of HCV, where acute HCV infection is a very limited health problem and infection can only be assessed by PCR, a more realistic goal might be to look for vaccines capable of protecting from chronic infection. We have preliminary evidence in chimpanzees that an HCV vaccine consisting of recombinant envelope proteins can elicit antibodies and inflammatory CD4+ T cell responses which can prevent chronic infection in the majority of vaccinees. Although the scientific and clinical challenges that need to be addressed are still substantial, advances in recombinant protein technology, novel adjuvants, and DNA vaccines, will be key in developing strategies to generate protective immunity against chronic HCV infection.