The JNK signaling pathway against titanium-particle-induced osteoclastogenesis and bone resorption in vivo

OBJECTIVE

The c-Jun N-terminal kinases (JNK) signaling pathway may be involved in the regulation of osteoclast development. The purpose of this investigation was to investigate whether SB600125, a JNK inhibitor, could attenuate titanium-particle-induced inflammatory osteolysis in vivo.

MATERIALS AND METHODS

A total of 45 mice were randomly divided into a Sham group, a Titanium group, and a Titanium + JNK inhibitor group, 15 mice per group. After establishing an air pouch bone graft model, we injected phosphate-buffered saline (PBS), titanium particles, or titanium particles + JNK inhibitor into the air pouch of the three groups. The pouch membranes containing bone implants were taken for morphological and molecular analysis 14 days after the mice were sacrificed.

RESULTS

General morphological structure observation results, Hematoxylin and Eosin (H&E)-Stained Sections, anti-tartaric acid phosphatase (TRAP) staining, and the transmission electron microscope showed that SB600125, by inhibiting the expression of JNK, attenuated titanium particle-induced inflammatory osteolysis (p<0.05). Immunohistochemical appearance results and reverse transcription-polymerase chain reaction (RT-PCR) results showed SB600125 reduced expression of IL-6, and TNF-α in osteolytic sites stimulated with wear debris (p<0.05). The Western blot results showed the expression of the p-JNK protein in the titanium particle + SB600125 group was significantly reduced compared to the titanium particle stimulation group (p<0.05).

CONCLUSIONS

Interfering with the JNK signaling pathway may be beneficial in reducing osteolysis, providing a therapeutic target for preventing and treating aseptic loosening caused by debris-induced inflammatory osteolysis.

Thermally modified tourmaline enhances hydrogen production by influencing hydrolysis acidification in two stages during dark fermentation of corn stover

This study investigated the influence of thermally modified tourmaline (Tur) on hydrogen production during the dark fermentation of corn stover. Single-factor experimental results revealed influencing factors of particle size, mass, and temperature. Optimization of the experimental process was achieved using the Box-Behnken design, reaching optimum at conditions of 407 °C, 910-mesh, and 6.2 g. The principle analysis experiment showed that the Tur-enhanced group (Tur_En) amplified cumulative hydrogen production by elevating hydrogen production during the sugar-production stage. The Tur_En group's cumulative hydrogen production was measured at 396.2 ± 40.3 (mL/g VS), marking a 34.2% increase compared to the control group. Analysis of microbial diversity indicated that Firmicutes and Bacteroidota emerged as dominant colonies in both stages. Tur facilitated hydrogen production by stimulating the activity of Firmicutes. This study suggests a highly effective Tur-enhanced technology for hydrogen production from corn stover and elucidates the principles underpinning this method from two stages.

A low-cost edge AI-chip-based system for real-time algae species classification and HAB prediction

Harmful Algal Blooms (HAB) are damaging to ecosystem functions and pose challenges to environmental and fisheries management. The key to HAB management and understanding the complex algal growth dynamics is the development of robust systems for real-time monitoring of algae populations and species. Previous algae classification studies mainly rely on the combination of an in-situ imaging flow cytometer and an off-site lab-based algae classification model such as Random Forest (RF) for the analysis of high-throughput images. An on-site AI algae monitoring system on top of an edge AI chip embedded with the proposed Algal Morphology Deep Neural Network (AMDNN) model is developed to achieve real-time algae species classification and HAB prediction. Based on a detailed examination of real-world algae images, dataset augmentation is first performed: consisting of orientation, flipping, blurring, and Resizing with Aspect ratio Preserved (RAP). The dataset augmentation is shown to significantly improve classification performance which is superior to that of the competitive RF model. And the attention heatmaps show that for relatively regular-shaped algal species (e.g., Vicicitus), the model weights the color and texture information heavily; while the shape-related features are more important for complex-shaped algae (e.g., Chaetoceros). The AMDNN is tested on a dataset of 11,250 algae images containing the 25 most common HAB classes in Hong Kong subtropical waters with 99.87% test accuracy. Based on the fast and accurate algae classification, the AI-chip-based on-site system is applied to a one-month dataset in February 2020; the predicted trends of total cell counts and targeted HAB species counts are in good agreement with observations. The proposed edge AI algae monitoring system provides a platform for the development of practical HAB early warning systems that can effectively support environmental risk and fisheries management.

Circadian nuclear receptor Rev-erbalpha is expressed by platelets and potentiates platelet activation and thrombus formation

Background

Adverse cardiovascular events have day/night patterns with peaks in the morning, potentially related to endogenous circadian clock control of platelet activation. Circadian nuclear receptor Rev-erbα is an essential and negative component of the circadian clock.

Purpose

We aim to investigate the expression profile and biological function of Rev-erbα in platelets.

Methods and results

Here we report the presence and functions of circadian nuclear receptor Rev-erbα in human and mouse platelets. Both human and mouse platelet Rev-erbα showed a circadian rhythm that positively correlated with platelet aggregation. Global Rev-erbα knockout and platelet-specific Rev-erbα knockout mice exhibited defective in hemostasis as assessed by prolonged tail-bleeding times. Rev-erbα deletion also reduced ferric chloride-induced carotid arterial occlusive thrombosis, prevented collagen/epinephrine-induced pulmonary thromboembolism, and protected against microvascular microthrombi obstruction and infarct expansion in an acute myocardial infarction model. In vitro thrombus formation assessed by CD41-labeled platelet fluorescence intensity was significantly reduced in Rev-erbα knockout mouse blood. Platelets from Rev-erbα knockout mice exhibited impaired agonist-induced aggregation responses, integrin αIIbβ3 activation and α-granule release. Consistently, pharmacological inhibition of Rev-erbα by specific antagonists decreased platelet activation markers in both mouse and human platelets. Mechanistically, mass spectrometry and co-immunoprecipitation analyses revealed that Rev-erbα potentiated platelet activation via oligophrenin-1-mediated RhoA/ERM (ezrin/radixin/moesin) pathway.

Conclusion

We provide the first evidence that circadian protein Rev-erbα is functionally expressed in platelets and potentiates platelet activation and thrombus formation. Rev-erbα may serve as a novel therapeutic target for managing thrombosis-based cardiovascular disease.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by grants from the National Science Fund for Distinguished Young Scholars (81625002), the National Natural Science Foundation of China (81930007).

Characteristics of US military personnel with atrial fibrillation and associated deployment and retention rates

INTRODUCTION

Atrial fibrillation (AF) is an arrhythmia impacting military occupational performances. Despite being a recognised disqualifying condition, there is no literature describing US military service members with AF. This study aims to describe members with AF diagnoses, the distribution of treatment strategies and associated deployment and retention rates.

METHODS

Active duty service members identified with AF from 2004 to 2019 were investigated. Cardiovascular profiles, AF management strategies and military dispositions were assessed by electronic medical record review.

RESULTS

386 service members (mean age 35.0±9.4 years; 94% paroxysmal AF) with AF diagnoses were identified. 91 (24%) had hypertension followed by 75 (19%) with sleep apnoea. Mean CHA₂DS₂-VASc scores were low (0.39±0.65). Rhythm treatments were used in 173 (45%) followed by rate control strategies in 155 (40%). 161 (42%) underwent pulmonary vein isolation (PVI). In subgroup analysis of 365 personnel, 147 (40%) deployed and 248 (68%) remained active duty after AF diagnosis. Deployment and retention rates did not differ between those who received no medical therapy, rate control or rhythm strategies (p=0.9039 and p=0.6192, respectively). PVI did not significantly impact deployment or retention rates (p=0.3903 and p=0.0929, respectively).

CONCLUSION

Service members with AF are young with few AF risk factors. Rate and rhythm medical therapies were used evenly. Over two-thirds met retention standards and 40% deployed after diagnosis. There were no differences in deployment or retention between groups who receive rate therapy, rhythm medical therapy or PVI. Prospective evaluation of the efficacy of specific AF therapies on AF burden and symptomatology in service members is needed.

Trabecular microstructure is influenced by race and sex in Black and White young adults

Lower fracture rates in Black men and women compared to their White counterparts are incompletely understood. High-resolution imaging specific to trabecular bone may provide insight. Black participants have enhanced trabecular morphology. These differences may contribute to the lower fracture risk in Black versus White individuals.

INTRODUCTION

Lower fracture rates in Black men and women compared to their White counterparts may be explained by favorable bone microstructure in Black individuals. Individual trabecular segmentation (ITS) analysis, which characterizes the alignment and plate- and rod-like nature of trabecular bone using high-resolution peripheral quantitative computed tomography (HR-pQCT), may provide insight into trabecular differences by race/ethnic origin.

PURPOSE

We determined differences in trabecular bone microarchitecture, connectivity, and alignment according to race/ethnic origin and sex in young adults.

METHODS

We analyzed HR-pQCT scans of 184 adult (24.2 ± 3.4 years) women (n = 51 Black, n = 50 White) and men (n = 34 Black, n = 49 White). We used ANCOVA to compare bone outcomes, and adjusted for age, height, and weight.

RESULTS

Overall, the effect of race on bone outcomes did not differ by sex, and the effect of sex on bone outcomes did not differ by race. After adjusting for covariates, Black participants and men of both races had greater trabecular plate volume fraction, plate thickness, plate number density, plate surface area, and greater axial alignment of trabeculae, leading to higher trabecular bone stiffness compared to White participants and women, respectively (p < 0.05 for all).

CONCLUSION

These findings demonstrate that more favorable bone microarchitecture in Black individuals compared to White individuals and in men compared to women is not unique to the cortical bone compartment. Enhanced plate-like morphology and greater trabecular axial alignment, established in young adulthood, may contribute to the improved bone strength and lower fracture risk in Black versus White individuals and in men compared to women.

Abstract P6-12-17: Identifying risk factors and effect modifiers of trastuzumab-induced cardiotoxicity among multi-ethnic women with early-stage HER2-positive breast cancer

Introduction: Trastuzumab-based adjuvant therapy is the current standard of care for early-stage HER2-positive breast cancer. However, trastuzumab has also been associated with an increased risk of cardiotoxicity, especially when given following an anthracycline. Trastuzumab-induced cardiotoxicity (TIC) can present as asymptomatic left ventricular ejection fraction (LVEF) decline or symptomatic heart failure. Our objective was to identify predictors of TIC among multi-ethnic patients with early-stage HER2-positive breast cancer. Unlike prior observational studies, our study included a high representation of racial/ethnic minorities, who are at increased risk of cardiovascular disease (CVD) compared to non-Hispanic whites.

Methods: We conducted a retrospective cohort study in patients with stage I-III HER2-positive breast cancer, diagnosed from 2007 to 2015 at Columbia University Medical Center (CUMC) in New York, NY, who had received adjuvant trastuzumab therapy. Participants had at least two serial echocardiograms or MUGA scans to assess TIC, which was defined as at least a 10% decrease in LVEF from baseline or LVEF &lt;50%. LVEF recovery was defined as at least a 10% increase in LVEF or LVEF &gt;50%. We conducted descriptive statistics and univariate and multivariable logistic regression to estimate the associations between socio-demographic factors, breast tumor and treatment characteristics, and CVD risk factors (including smoking status, body mass index [BMI], hypertension, diabetes, hyperlipidemia, coronary artery disease) and TIC. Interactions between race/ethnicity and CVD risk factors were assessed using a logistic regression model.

Results: In our study population (N=279), the mean age was 52.7 years (standard deviation, 12.1) with 36.6% non-Hispanic white, 18.3% non-Hispanic black, 34.8% Hispanic, and 10.4% Asian patients. There were no differences by race/ethnicity in tumor and treatment characteristics (over half had prior anthracyclines), but racial/ethnic minorities had higher BMI and were more likely to have hypertension compared to non-Hispanic whites. About a third of patients developed TIC and 14.7% had an LVEF decline to &lt;50%, of which 15 (16.1%) experienced LVEF recovery. In multivariable analysis, prior anthracycline use and hypertension were significantly associated with increased odds of developing TIC (odds ratio [OR]: 2.25, 95% confidence interval [CI]: 1.25, 4.06; OR: 2.13, 95% CI: 1.15, 3.93, respectively). There was a significant interaction (p=0.027) between race/ethnicity and hypertension on odds of developing TIC with hypertensive non-Hispanic white patients experiencing 6.05 (95% CI: 2.19, 16.75) times the odds of developing TIC compared to non-hypertensive non-Hispanic whites.

Discussion: We observed a higher incidence of TIC and lower incidence of LVEF recovery compared to previous clinical trials. Given patient selection for clinical trials, our results may be more representative of clinical practice settings. We found a particularly high risk among non-Hispanic white patients with hypertension. Patients with hypertension may require closer blood pressure monitoring and treatment with anti-hypertensives in order to reduce risk of developing cardiotoxicity.

Citation Format: Yuan A, Topkara V, Hershman DL, Kalinsky K, Accordino MK, Trivedi MS, Yu A, Genkinger JM, Crew KD. Identifying risk factors and effect modifiers of trastuzumab-induced cardiotoxicity among multi-ethnic women with early-stage HER2-positive breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-17.

Oral chronic GVHD outcomes and resource utilization: a subanalysis from the chronic GVHD consortium

OBJECTIVES

This study evaluated the extent to which oral chronic graft-versus-host disease (cGVHD) consensus assessments are predictive of management across institutions with and without oral medicine (OM) centers, and whether ancillary care guidelines are followed within clinical practice.

METHODS

Longitudinal oral cGVHD data were abstracted from the cGVHD Consortium, and additional mouth-specific management data were analyzed across five transplant centers.

RESULTS

Seventy-nine patients with 656 visits were observed for a median of 7.1 months with one visit per follow-up month. Ancillary therapies for oral cGVHD were prescribed for 67% of patients for a median of 0.46 months (per follow-up month) at OM centers and 0.78 months at non-OM centers. Patients treated with ancillary therapy were more likely to have an National Institutes of Health (NIH) mouth score of ≥1 (P < 0.001, odds ratio: 5.1) and mouth pain (P = 0.01, odds ratio: 2.6). The odds ratios of receiving ancillary therapy from OM experts were higher than transplant physicians (53%; P = 0.03).

CONCLUSIONS

Oral cGVHD consensus assessments corresponding with ancillary therapy use were mouth pain and NIH mouth score, with higher odds ratios of receiving therapy from OM experts. Ancillary care guidelines for oral cGVHD are reflected in academic clinical practice with respect to utilization of recommended prescriptions.

Vaginal deployment and tenofovir delivery by microbicide gels

Gels are one of the soft material platforms being evaluated to deliver topically acting anti-HIV drugs (microbicides) to the vaginal environment. For each drug, its loaded concentration, gel properties and applied volume, and frequency of dosing can be designed to optimize PK and, thence, PD. These factors also impact user sensory perceptions and acceptability. Deterministic compartmental modeling of vaginal deployment and drug delivery achieved by test gels can help delineate how multiple parameters characterizing drug, vehicle, vaginal environment, and dosing govern details of PK and PD and also gel leakage from the canal. Such microbicide delivery is a transport process combining convection, e.g., from gel spreading along the vaginal canal, with drug diffusion in multiple compartments, including gel, mucosal epithelium, and stroma. The present work builds upon prior models of gel coating flows and drug diffusion (without convection) in the vaginal environment. It combines and extends these initial approaches in several key ways, including: (1) linking convective drug transport due to gel spreading with drug diffusion and (2) accounting for natural variations in dimensions of the canal and the site of gel placement therein. Results are obtained for a leading microbicide drug, tenofovir, delivered by three prototype microbicide gels, with a range of rheological properties. The model includes phosphorylation of tenofovir to tenofovir diphosphate (which manifests reverse transcriptase activity in host cells), the stromal concentration distributions of which are related to reference prophylactic values against HIV. This yields a computed summary measure related to gel protection ("percent protected"). Analyses illustrate tradeoffs amongst gel properties, drug loading, volume and site of placement, and vaginal dimensions, in the time and space history of gel distribution and tenofovir transport to sites of its anti-HIV action and concentrations and potential prophylactic actions of tenofovir diphosphate therein.

High-throughput screening identifies small molecules that enhance the pharmacological effects of oligonucleotides

The therapeutic use of antisense and siRNA oligonucleotides has been constrained by the limited ability of these membrane-impermeable molecules to reach their intracellular sites of action. We sought to address this problem using small organic molecules to enhance the effects of oligonucleotides by modulating their intracellular trafficking and release from endosomes. A high-throughput screen of multiple small molecule libraries yielded several hits that markedly potentiated the actions of splice switching oligonucleotides in cell culture. These compounds also enhanced the effects of antisense and siRNA oligonucleotides. The hit compounds preferentially caused release of fluorescent oligonucleotides from late endosomes rather than other intracellular compartments. Studies in a transgenic mouse model indicated that these compounds could enhance the in vivo effects of a splice-switching oligonucleotide without causing significant toxicity. These observations suggest that selected small molecule enhancers may eventually be of value in oligonucleotide-based therapeutics.

NanoFerrite particle based radioimmunonanoparticles: binding affinity and in vivo pharmacokinetics

Dextran and PEG-coated iron oxide nanoparticles (NP), when suitably modified to enable conjugation with molecular targeting agents, provide opportunities to target cancer cells. Monoclonal antibodies, scFv, and peptides conjugated to 20 nm NP have been reported to target cancer for imaging and alternating magnetic field (AMF) therapy. The physical characteristics of NPs can affect their in vivo performance. Surface morphology, surface charge density, and particle size are considered important factors that determine pharmacokinetics, toxicity, and biodistribution. New NanoFerrite (NF) particles having improved specific AMF absorption rates and diameters of 30 and 100 nm were studied to evaluate the variation in their in vitro and in vivo characteristics in comparison to the previously studied 20 nm superparamagnetic iron oxide (SPIO) NP. SPIO NP 20 nm and NF NP 30 and 100 nm were conjugated to (111)In-DOTA-ChL6, a radioimmunoconjugate. Radioimmunoconjugates were conjugated to NPs using 25 microg of RIC/mg of NP by carbodiimide chemistry. The radioimmunonanoparticles (RINP) were purified and characterized by PAGE, cellulose acetate electrophoresis (CAE), live cell binding assays, and pharmacokinetics in athymic mice bearing human breast cancer (HBT 3477) xenografts. RINP (2.2 mg) were injected iv and whole body; blood and tissue data were collected at 4, 24, and 48 h. The preparations used for animal study were >90% monomeric by PAGE and CAE. The immunoreactivity of the RINP was 40-60% compared to (111)In-ChL6. Specific activities of the doses were 20-25 microCi/2.2 mg and 6-11 microg of mAb/2.2 mg of NP. Mean tumor uptakes (% ID/g +/- SD) of each SPIO 20 nm, NF 30 nm, and 100 nm RINP at 48 h were 9.00 +/- 0.8 (20 nm), 3.0 +/- 0.3 (30 nm), and 4.5 +/- 0.8 (100 nm), respectively; the ranges of tissue uptakes were liver (16-32 +/- 1-8), kidney (7.0-15 +/- 1), spleen (8-17 +/- 3-8), lymph nodes 5-6 +/- 1-2), and lung (2.0-4 +/- 0.1-2). In conclusion, this study demonstrated that 100 nm NF NP could be conjugated to (111)In-mAb so that the resulting RINP had characteristics suitable for AMF therapy. Although 100 nm RINP targeted tumor less than 20 nm SPIO RINP, their heating capacity is typically 6 times greater, suggesting the 100 nm NF RINP could still deliver better therapy with AMF.

Preventable deaths in patients admitted from emergency department

BACKGROUND

There is limited data about how appropriate medical care is in the emergency department (ED).

OBJECTIVES

To investigate the rate and types of preventable deaths among patients with early mortality after emergency admission from the ED.

METHODS

We retrospectively reviewed charts of early mortality (defined as mortality which occurred within 24 hours after admission from the ED) over a 3 year period. Those patients with terminal cancer or out of hospital cardiac arrest (OHCA) at presentation were excluded. Two independent assessors reviewed each eligible chart and determined whether early mortality was preventable. Any disagreements were resolved through discussion between the investigators. A mortality event was considered preventable if actions or missed actions were identified that would have prevented the death. The types of preventability were categorised as misdiagnosis, delayed diagnosis, and inappropriate medical management. Interrater reliability in the initial determination was assessed using Cohen kappa statistic.

RESULTS

Over a 3 year period, 210 early mortality cases were identified. Excluding patients with terminal cancer or OHCA, the rate of preventable deaths was 25.8% (32/124). The types of preventability were inappropriate medical management (17 patients), delayed diagnosis (eight), and misdiagnosis (seven). There was good agreement between assessors with a Cohen kappa statistic of 0.81.

CONCLUSIONS

Preventable deaths in emergency admitted patients with early mortality are not uncommon. Analysis and identification of preventability early mortality by using a chart based method may be used as a quality assurance index in emergency medical care.

Spontaneous pneumothorax associated with ankylosing spondylitis

OBJECTIVE

To review the incidence and clinical characteristics of spontaneous pneumothorax in patients with ankylosing spondylitis (AS).

METHODS

This is a retrospective observational cohort study. Chest radiographs and medical records of patients with a diagnosis of AS from 1993 to 2003 in a tertiary referral centre were reviewed.

RESULTS

A total of 1028 patients with a diagnosis of AS were identified from July 1993 to July 2003. Twenty-two patients had typical apical lung fibrotic changes in the chest radiographs (22/1028, 2.1%). Three of these patients (3/22, 13.6%) with lung disease had pneumothorax. Two patients had recurrences and received video-assisted thoracoscopic surgery (VATS) on the second attack. The third patient received talc pleurodesis on the first attack and did not have a recurrence. The incidence of spontaneous pneumothorax in patients with AS was 0.29% (3/1028) with an incidence density of 64.85/100,000 patient-yr (95% confidence interval: 66.17-63.57/100,000).

CONCLUSION

Spontaneous pneumothorax appears to be exceedingly rare in AS unless there is an underlying fibrocystic lung disease, in which case its occurrence is not uncommon. Cigarette smoking may be an important co-factor. Once developed, recurrences are common even after treatment. Prophylactic procedures should thus be considered for the first attack of spontaneous pneumothorax.

MINERVA: a multi-modality plugin-based radiation therapy treatment planning system

Researchers at the INEEL, MSU, LLNL and UCD have undertaken development of MINERVA, a patient-centric, multi-modal, radiation treatment planning system, which can be used for planning and analysing several radiotherapy modalities, either singly or combined, using common treatment planning tools. It employs an integrated, lightweight plugin architecture to accommodate multi-modal treatment planning using standard interface components. The design also facilitates the future integration of improved planning technologies. The code is being developed with the Java programming language for interoperability. The MINERVA design includes the image processing, model definition and data analysis modules with a central module to coordinate communication and data transfer. Dose calculation is performed by source and transport plugin modules, which communicate either directly through the database or through MINERVA's openly published, extensible markup language (XML)-based application programmer's interface (API). All internal data are managed by a database management system and can be exported to other applications or new installations through the API data formats. A full computation path has been established for molecular-targeted radiotherapy treatment planning, with additional treatment modalities presently under development.

Dissection of K+ currents in Caenorhabditis elegans muscle cells by genetics and RNA interference

GFP-promoter experiments have previously shown that at least nine genes encoding potassium channel subunits are expressed in Caenorhabditis elegans muscle. By using genetic, RNA interference, and physiological techniques we revealed the molecular identity of the major components of the outward K+ currents in body wall muscle cells in culture. We found that under physiological conditions, outward current is dominated by the products of only two genes, Shaker (Kv1) and Shal (Kv4), both expressing voltage-dependent potassium channels. Other channels may be held in reserve to respond to particular circumstances. Because GFP-promoter experiments indicated that slo-2 expression is prominent, we created a deletion mutant to identify the SLO-2 current in vivo. In both whole-cell and single-channel modes, in vivo SLO-2 channels were active only when intracellular Ca2+ and Cl- were raised above normal physiological conditions, as occurs during hypoxia. Under such conditions, SLO-2 is the largest outward current, contributing up to 87% of the total current. Other channels are present in muscle, but our results suggest that they are unlikely to contribute a large outward component under physiological conditions. However, they, too, may contribute currents conditional on other factors. Hence, the picture that emerges is of a complex membrane with a small number of household conductances functioning under normal circumstances, but with additional conductances that are activated during unusual circumstances.

Enhanced therapeutic index of radioimmunotherapy (RIT) in prostate cancer patients: comparison of radiation dosimetry for 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid (DOTA)-peptide versus 2IT-DOTA monoclonal antibody linkage for RIT

PURPOSE

Radioimmunotherapy delivered by radiometal immunoconjugates and followed by marrow support is dose limited by deposition of radioactivity in normal organs. To increase elimination of radioactivity from the liver and body and, thus, minimize hepatic radiation dose, a peptide having a specific cathepsin B cleavage site was placed between the radiometal chelate DOTA (1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic acid) and the monoclonal antibody m170, and the comparative pharmacokinetics was evaluated in prostate cancer patients.

EXPERIMENTAL DESIGN

(111)In-DOTA-2IT-m170 and (111)In-DOTA-peptide-(GGGF)-m170, representing the same monoclonal antibody and chelate with and without the cleavable linkage, were studied in comparable groups of prostate cancer patients (17 with In-2IT-BAD-m170 and 8 with In-DOTA-peptide-m170). Pharmacokinetics over 7 days, calculated yttrium-90 radiation dosimetry, therapeutic index, and projected maximum tolerated injected yttrium-90 dose were evaluated.

RESULTS

The radioimmunoconjugates pharmacokinetics and calculated tumor and normal organ absorbed radiation dose (rads/mCi) were similar, except for a significant decrease in the mean dose to the liver (31%; P < 0.01) and lungs (31%; P < 0.01) with the DOTA-peptide immunoconjugates. Because mean tumor dose was not statistically different, this peptide linkage provided a significant increase in the therapeutic index for this tumor targeting radiopharmaceutical. If marrow support is adequate, the radiation dose historically tolerated by normal organs other than marrow would allow a 30% increase in the administered dose, resulting in a mean dose of 9500 rads to metastatic prostate cancer.

Diaminoindanes as microsomal triglyceride transfer protein inhibitors

The synthesis and biological activities of biarylamide-substituted diaminoindanes as microsomal triglyceride transfer protein (MTP) inhibitors are described. One of the more potent compounds, 8aR, inhibited both the secretion of apoB from Hep G2 cells and the MTP-mediated transfer of triglycerides between synthetic acceptor and donor liposomes with IC(50) values of 0.7 and 70 nM, respectively. In normolipidemic rats and dogs, oral administration of 8aR dose-dependently reduced both plasma triglycerides and total cholesterol. Moreover, in rats and dogs, 8aR also prevented the postprandial rise in plasma triglycerides following a bolus administration of a fat load. Because MTP inhibitors decrease very low density lipoprotein assembly in the liver, the potential for hepatic lipid accumulation was evaluated. In normolipidemic rats, hepatic cholesterol and triglyceride contents were dose-dependently increased by 8aR. However, hepatic lipid accumulation resulted in negligible change in total liver weight and was reversible after withdrawal of the compound.

Collapsin response mediator protein-1 and the invasion and metastasis of cancer cells

BACKGROUND

Numerous genetic changes are associated with metastasis and invasion of cancer cells. To identify differentially expressed invasion-associated genes, we screened a panel of lung cancer cell lines (CL(1-0), CL(1-1), CL(1-5), and CL(1-5)-F(4) in order of increasing invasive activity) for such genes and selected one gene, collapsin response mediator protein-1 (CRMP-1), to characterize.

METHODS

We used a microarray containing 9600 gene sequences to assess gene expression in the cell panel and selected the differentially expressed CRMP-1 gene for further study. We confirmed the differential expression of CRMP-1 with northern and western blot analyses. After transfecting and overexpressing CRMP-1 in highly invasive CL(1-5) cells, the cells were assessed morphologically and with an in vitro invasion assay. We used enhanced green fluorescent protein-tagged CRMP-1 and fluorescence microscopy to localize CRMP-1 intracellularly. CRMP-1 expression in 80 lung cancer specimens was determined by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). All statistical tests were two-sided.

RESULTS

Expression of CRMP-1 was inversely associated with invasive activity in the cell panel, an observation confirmed by northern and western blot analyses. CRMP-1-transfected CL(1-5) cells became rounded and had fewer filopodia and statistically significantly lower in vitro invasive activity than untransfected cells (all P< .001). During interphase, CRMP-1 protein was present uniformly throughout the cytoplasm and sometimes in the nucleus; during mitosis, CRMP-1 was associated with mitotic spindles, centrosomes, and the midbody (in late telophase). Real-time RT-PCR of lung cancer specimens showed that reduced expression of CRMP-1 was statistically significantly associated with advanced disease (stage III or IV; P = .010), lymph node metastasis (N1, N2, and N3; P =.043), early postoperative relapse (P = .030), and shorter survival (P = .016).

CONCLUSIONS

CRMP-1 appears to be involved in cancer invasion and metastasis and may be an invasion-suppressor gene.

Acute respiratory distress syndrome in a woman with heroin and methamphetamine misuse

Methamphetamine, heroin, and cannabis are three of the most commonly misused drugs in Asia. In Taiwan, cases of misuse of methamphetamine have been increasing. In this paper, we report the case of a 23-year-old woman who had a 10-year history of smoking methamphetamine and intermittent use of heroin for 3 to 4 years. She developed pulmonary toxic effects associated with misuse of heroin and methamphetamine. She was brought to the emergency room because of consciousness disturbance and acute respiratory failure. Her symptoms of rapid progression of refractory hypoxemia, ill-defined densities over both lung fields, and normal pulmonary artery wedge pressure were consistent with acute respiratory distress syndrome. Rapid resolution of infiltrations and improvement of oxygenation were observed after mechanical ventilation with positive end-expiratory pressure support and oxygen therapy. She was discharged on the fifteenth hospital day without any sequela except for mild exertional dyspnea.

[Effects of vascular endothelial growth factor on adhesion molecular expression of hepatocellular carcinoma HepG]

OBJECTIVE

To study the effect of vascular endothelial growth factor (VEGF) on homotypic adhesion and E-cadherin of hepatocellular carcinoma cells.

METHODS

We measured the function of homotypic adhesion with (3)H-TdR infiltration and the expression of E-cadherin with laser scanning confocal microscope.

RESULTS

After 60, 90, 120min, the values (dpm/min) of (3)H-TdR infiltration in HepG(2) cells induced by 1ng/ml, 5ng/ml VEGF were 1758.67+/-289.46, 1380.03+/-328.55, 2657.43 +/- 310.31 and 3124.30+/-262.14, 2245.60+/-273.24, 2091.52+/-213.84. The values by 10ng/ml VEGF were 1232.32+/-201.04, 2337.50+/-333.04, 2236.99 +/- 237.07, which were significantly lower than those in control group (P<0.05 or 0.01). The expression of E-cadherin in hepatocellular carcinoma cells induced by 5ng/ml VEGF was 352+/-56 and much lower than that in control group (757+/-103, P<0.01).

CONCLUSIONS

VEGF can decrease homotopic adhesion of hepatocellular carcinoma HepG(2) cell, which is connected with the less expression of E-cadherin in hepatocellular carcinoma HepG(2) cell.

Evolution tunes the excitability of individual neurons

The relationship between the genome and the evolution of the nervous system may differ between an animal like C. elegans with 302 neurons, and mammals with tens of billions of neurons. Here we report that a class of nonconserved potassium channels highly expanded in C. elegans may play a special role in the evolution of its nervous system. The C. elegans genome contains an extended gene family of potassium channels whose members fall into two evolutionary divergent classes. One class constitutes an ancient conserved "set" of K+ channels with orthologues in both humans and Drosophila and a second larger class made up of rapidly evolving genes unique to C. elegans. Chief among this second class are novel potassium channels having four transmembrane domains per subunit that function as regulated leak conductances to modulate cell electrical excitability. This inventory of novel potassium channels is far larger in C. elegans than in humans or Drosophila. We found that, unlike conserved channel genes, the majority of these genes are expressed in very few cells. We also identified DNA enhancer elements associated with these genes that direct gene expression to individual neurons. We conclude that C. elegans may maintain an exceptionally large inventory of these channels (as well as ligand-gated channels) as an adaptive mechanism to "fine tune" individual neurons, making the most of its limited circuitry.

Radioimmunotherapy with (111)In/(90)Y-2IT-BAD-m170 for metastatic prostate cancer

PURPOSE

Over 31,000 Americans die of androgen-independent metastatic prostate cancer each year. New strategies that do not involve hormonal manipulation but instead recognize the biochemical and molecular characteristics of prostate cancer are needed. Radioimmunotherapy (RIT) uses a tumor-specific monoclonal antibody to deliver systemic, targeted radiation to cancer. The objectives of this Phase I study of (111)In-2IT-BAD-m170 (for imaging) and (90)Y-2IT-BAD-m170 (for therapy) were to determine the toxicity and maximum tolerated dose (MTD), the specificity for targeting metastatic prostate cancer, and the efficacy for palliation of pain.

EXPERIMENTAL DESIGN

M170 is a mouse monoclonal antibody that targets adenocarcinomas. Patients with adequate renal and liver function, rising prostate-specific antigen, and androgen-independent metastatic prostate cancer were eligible. After estimation of dosimetry and pharmacokinetics with (111)In-2IT-BAD-m170, a single dose of (90)Y-2IT-BAD-m170 (0.185, 0.370, 0.555, or 0.740 GBq/m(2)) was administered to cohorts of three patients. Pain was assessed objectively by questionnaires before and for 8 weeks after RIT; weekly prostate-specific antigen levels were obtained for 2 months after RIT.

RESULTS

The MTD of (90)Y-2IT-BAD-m170 was 0.740 GBq/m(2) for patients that had up to 10% of the axial skeleton involved with prostate cancer. Toxicity was almost exclusively confined to reversible myelosuppression. Metastatic prostate cancer was targeted by (111)In-2IT-BAD-m170 in all 17 patients. The mean radiation dose delivered to 39 bone and 18 nodal metastases by (90)Y-2IT-BAD-m170 was 10.5 Gy/GBq (range 2.8-25.1). Thirteen of 17 patients reported pain before (90)Y-2IT-BAD-m170; 7 of these 13 had a partial or complete resolution of pain that lasted an average of 4.3 weeks.

CONCLUSIONS

This study determined the MTD of (111)In/(90)Y-2IT-BAD-m170 in patients with metastatic prostate cancer. The drugs were well tolerated, targeted metastases, and temporarily palliated pain.

Giant vacuoles observed in Dictyostelium discoideum

Large intracellular vacuoles, >4 microm in diameter and either round or oval-shaped, were observed infrequently in Dictyostelium discoideum amoebae of axenically-grown strain AX2 (only 1 in 10(6)-10(8)cells). These previously unreported single or multiple 'giant' vacuoles were more common, however, in newly germinated KAX3 cells (0.55% of the population) and AT-K(neg), a strain that lacks an esterase (0.47% of the population). A vacuolar H(+)-ATPase was enriched in their membranes of intracellular giant vacuoles, indicating that the vacuoles were related possibly to both endosomes and the contractile vacuole compartment. When monitored over time, giant vacuoles protruded from, and retracted back into cells under hyperosmotic conditions, suggesting an osmoregulatory role for these vacuoles. Some of the intracellular and protruded giant vacuoles harbored a fluid-phase marker, fluorescein-labeled dextran, implying a pinocytotic origin for the vacuoles.

Calcium requirement for efficient phagocytosis by Dictyostelium discoideum

Extracellular EDTA suppressed in a dose-dependent manner the phagocytosis of yeast particles by Dictyostelium discoideum cells. Activity was restored fully by the addition of Ca(2+), and partially by the addition of Mn(2+)or Zn(2+), but Mg(2+)was ineffective. The pH-sensitive, Ca(2+)-specific chelator EGTA also inhibited phagocytosis at pH 7.5, but not at pH 5, and Ca(2+)restored the inhibited phagocytosis. In contrast, pinocytosis was unaffected by EDTA. Consistent with the idea that Ca(2+)was required for phagocytosis, D. discoideum growth on bacteria was inhibited by EDTA, which was then restored by the addition of Ca(2+). It is concluded that Ca(2+)was needed for efficient phagocytosis by D. discoideum amoebae. A search for Ca(2+)-dependent membrane proteins enriched in phagosomes revealed the presence of p24, a Ca(2+)-dependent cell-cell adhesion molecule-1 (DdCAD-1) that could be the target of the observed EDTA and EGTA inhibition. DdCAD-1-minus cells, however, had normal phagocytic activity. Furthermore, phagocytosis was inhibited by EDTA and rescued by Ca(2+)in the mutant just as in wild type. Thus, DdCAD-1 was not responsible for the observed Ca(2+)-dependence of phagocytosis, indicating that one or more different Ca(2+)-dependent molecule(s) was involved in the process.

Value of chest sonography in the diagnosis and management of acute chest disease

PURPOSE

The aim of this study was to investigate the value of chest sonography in the diagnosis and management of patients with chest radiograph opacities in an emergency department.

METHODS

Seventy-eight patients with acute chest complaints whose chest radiographs showed opacities underwent chest sonography. The initial diagnosis (based on clinical manifestations and the chest radiograph), the sonographic diagnosis (before any invasive procedures), and the final diagnosis were compared. The impact of chest sonography on the management of patients with chest opacities was also analyzed.

RESULTS

The initial diagnosis was in concordance with the final diagnosis in 60 (77%) of the 78 patients, while the sonographic diagnosis was in concordance with the final diagnosis in 75 (96%) of the patients. Chest sonography therefore significantly increased the rate of correct diagnoses from 77% (95% confidence interval, 67-87%) to 96% (95% confidence interval, 92-100%; p < 0.0001). Sonography provided new information in 52 patients (67%): a different diagnosis from the initial diagnosis in 18 patients and additional diagnostic information in 34 patients. New information gained from sonography affected the management of 35 patients. Sonography also provided help in guiding 42 (70%) of 60 invasive diagnostic procedures and 22 (73%) of 30 invasive therapeutic procedures for which chest radiography and physical examination had failed to or were unsuitable to provide guidance. Overall, sonography assisted in the management of 64 (82%) of 78 patients. Sonography was of no benefit in 14 patients (18%).

CONCLUSIONS

We conclude that chest sonography can complement chest radiography and is of value in the diagnosis and management of emergency department patients with acute chest diseases presenting as opacities on chest radiographs.

Vascular endothelial growth factor 189 mRNA isoform expression specifically correlates with tumor angiogenesis, patient survival, and postoperative relapse in non-small-cell lung cancer

PURPOSE

The purpose of this study was to evaluate the correlation between the expression of four different vascular endothelial growth factor (VEGF) mRNA isoforms (VEGF121, VEGF165, VEGF 189, and VEGF206) and the clinicopathologic characteristics, tumor angiogenesis, and outcome of patients with non-small-cell lung cancer.

PATIENTS AND METHODS

We examined the expression of four different VEGF mRNA isoforms in 57 non-small-cell lung cancers using reverse transcriptase polymerase chain reaction and the tumor angiogenesis using immunohistochemical staining.

RESULTS

All 57 lung cancer samples expressed the VEGF121, VEGF165, and VEGF189 mRNA isoforms, and three expressed the VEGF206 mRNA isoform. A high tumoral VEGF189 mRNA isoform expression ratio was associated with a high intratumoral microvessel count (P = .013), short survival (< 24 months; P = .001), and early postoperative relapse (< 12 months; P = .001). Survival and postoperative relapse time were significantly shorter in patients with a high compared with a low tumor VEGF189 mRNA isoform expression ratio (P = .0001 and P = .0086, respectively, log-rank test). In contrast, the VEGF165 and VEGF 206 mRNA isoform expression ratios showed no statistical correlation with tumor angiogenesis, postoperative relapse time, or survival. A high VEGF121 mRNA isoform expression ratio was associated with short survival (< 24 months) and early relapse (< 12 months). Multivariate analysis showed that VEGF 189 mRNA isoform expression, microvessel count, and nodal status were the most important independent prognostic factors for patient survival and postoperation recurrence.

CONCLUSION

The VEGF189 mRNA isoform expression ratio shows a greater correlation with tumor angiogenesis, postoperative relapse time, and survival than do the expression ratios for the VEGF121, VEGF165, and VEGF206 mRNA isoforms and can be used as a prognostic indicator for patients with non-small-cell lung cancers.

Correlation of total VEGF mRNA and protein expression with histologic type, tumor angiogenesis, patient survival and timing of relapse in non-small-cell lung cancer

We have quantified the expression of all 4 isoforms of vascular endothelial growth factor (VEGF) mRNA in non-small-cell lung cancer (NSCLC) using a new kinetic quantitative PCR method, real-time quantitative (RTQ) RT-PCR, and investigated the association between VEGF expression at the mRNA and protein levels and the clinicopathologic variables, tumor angiogenesis, patient survival and timing of relapse. Surgical tumor specimens from 72 NCSLC patients (37 squamous-cell carcinomas, 35 adenocarcinomas) were examined. Twenty-eight patients had stage I, 10 stage II and 34 stage IIIA or IIIB disease. Total VEGF mRNA (all 4 isoforms) was quantified by RTQ RT-PCR, while VEGF protein expression and microvessel number in tumors were assessed immunohistochemically. VEGF mRNA was detected in all 72 tumor samples at significantly higher levels than in adjacent normal tissue. Tumoral VEGF mRNA levels correlated strongly with the VEGF protein staining score and microvessel count. Adenocarcinomas showed significantly higher VEGF mRNA expression and a higher protein staining score than squamous-cell carcinomas. High tumoral VEGF mRNA expression was associated with advanced (IIIA or IIIB) tumor stage, lymph node metastasis, high tumoral microvessel counts, short patient survival (<24 months) and early relapse (<12 months), while a high VEGF protein staining score was associated with high tumoral microvessel counts, short patient survival and early relapse. Patients with high tumoral levels of both VEGF mRNA and protein had significantly shorter survival and earlier relapse. In multivariate analysis, the VEGF protein staining score and nodal status were the most important independent predictors of survival and recurrence. We conclude that RTQ RT-PCR is a sensitive method for detecting and quantifying VEGF mRNA expression in NSCLC and that the expression levels of total VEGF mRNA and protein in NSCLC are strongly associated with histologic type, tumor angiogenesis, survival and timing of relapse. High VEGF expression in adenocarcinomas may contribute to their greater metastatic potential.

Role of esterase gp70 and its influence on growth and development of Dictyostelium discoideum

Gp70 is an esterase originally called crystal protein because of its presence in crystalline structures in aggregation-competent Dictyostelium discoideum cells. Although postulated to break down spore coats, the function of gp70 in vivo was incompletely investigated. Our immunolocalization and biochemical studies of vegetative D. discoideum amoebae show that gp70 was recruited to phagosomes and found in lysosomes. Purified gp70 was effective at hydrolyzing naphthyl substrates with acyl chains typical of lipids and lipopolysaccharides, indicating that the gp70 was involved in digesting endocytosed molecules. The activity of purified gp70 was inhibited by reductants that retarded its electrophoretic mobility and verified the presence of intramolecular disulfide bonds predicted by its amino acid sequence. Compared to wild-type cells, cells overexpressing gp70 were more phagocytically active, had shorter generation times, and produced more fruiting bodies per unit area, while cells lacking gp70 were phagocytically less active with longer doubling times, developed more slowly, and had significantly fewer fruiting bodies per unit area. Consistent with the phenotype of a disrupted metabolism, one-third of the gp70-minus cells were large and multinucleated. Together, these results indicated that despite its crystalline appearance, gp70 was an active esterase involved in both the growth and the development of D. discoideum.

131I-Lym-1 in mice implanted with human Burkitt's lymphoma (Raji) tumors: loss of tumor specificity due to radiolysis

Preliminary evaluations of 125I-labeled Lym-1, an anti-lymphoma mouse IgG2a monoclonal antibody, demonstrated favorable tumor uptake in mice bearing human Burkitt's lymphoma (Raji) tumors. In this study, the pharmacokinetics of 125I- and 131I-Lym-1, and the dosimetry, efficacy, and toxicity of 131I-Lym-1 in Raji-tumored mice were evaluated.

METHODS

Lym-1 was radioiodinated by the chloramine-T method and analyzed for monomeric fraction and immunoreactivity (antigen cell binding, relative to unmodified Lym-1). Nude mice bearing Raji tumors (20-500 mm3) received 1.5 MBq (40 microCi) 125I-Lym-1, or 1.5, 7.4, 14.8, or 18.5 MBq (40, 200, 400, or 500 microCi) 131I-Lym-1. Pharmacokinetic data (total body and blood clearance and biodistribution) were used to estimate radiation dosimetry. Mini-thermoluminescent dosimetry (TLD) was also used to measure radiation dosimetry directly for 7 days after injection of 131I-Lym-1. Tumor size, survival, body weight, and blood counts were monitored for 60 days to evaluate therapeutic efficacy and toxicity of 131I-Lym-1.

RESULTS

At the time of injection, the mean quality assurance (QA) values for 125I-Lym-1 were 100% monomer and 100% relative immunoreactivity; the corresponding values for 131I-Lym-1 were 73% and 66%, indicating that radiolysis had occurred during the interval between radiolabeling and injection. 125I-Lym-1 exhibited high and sustained concentration in tumors relative to normal organs, whereas 131I-Lym-1 did not. Assuming identical pharmacokinetic behavior to 125I-Lym-1, 131I-Lym-1 would deliver radiation doses of 3.45, 0.83, 1.03, 0.34, and 0.56 Gy per MBq injected (12.8, 3.1, 3.8, 1.3, and 2.1 rad/microCi), to tumor, liver, lungs, total body, and marrow, respectively. When the actual pharmacokinetic data for 131I-Lym-1 (1.5 MBq) were used to estimate dosimetry, corresponding values of 0.51, 0.72, 0.49, 0.31, and 0.41 Gy/MBq (1.9, 2.7, 1.8, 1.1, and 1.5 rad/microCi) were obtained. Similar values were obtained for mice receiving 7.4 or 14.8 MBq of 131I-Lym-1. Similarly, TLD data indicated little preferential radiation dosimetry to tumor. Response rates (cure + CR + PR) for mice receiving 0, 7.4, 14.8, and 18.5 MBq of 131I-Lym-1 were 8%, 7%, 21%, and 45%, respectively. The LD50/30 dose of 131I-Lym-1 was 12.7 MBq (343 microCi).

CONCLUSIONS

125I-Lym-1 exhibited high and sustained concentration in Raji tumors in mice, indicating excellent therapeutic potential for 131I-Lym-1. However, in vitro QA results for 131I-Lym-1 indicated that radiolysis had occurred, and 131I-Lym-1 demonstrated little accumulation in tumor, or preferential radiation dosimetry to tumor in the same model.

Tubulin and neurofilament proteins are transported differently in axons of chicken motoneurons

1. We previously showed that actin is transported in an unassembled form with its associated proteins actin depolymerizing factor, cofilin, and profilin. Here we examine the specific activities of radioactively labeled tubulin and neurofilament proteins in subcellular fractions of the chicken sciatic nerve following injection of L-[35S]methionine into the lumbar spinal cord. 2. At intervals of 12 and 20 days after injection, nerves were cut into 1-cm segments and separated into Triton X-100-soluble and particulate fractions. Analysis of the fractions by high-resolution two-dimensional gel electrophoresis, immunoblotting, fluorography, and computer densitometry showed that tubulin was transported as a unimodal wave at a slower average rate (2-2.5 mm/day) than actin (4-5 mm/day). Moreover, the specific activity of soluble tubulin was five times that of its particulate form, indicating that tubulin is transported in a dimeric or small oligomeric form and is assembled into stationary microtubules. 3. Neurofilament triplet proteins were detected only in the particulate fractions and transported at a slower average rate (1 mm/day) than either actin or tubulin. 4. Our results indicate that the tubulin was transported in an unpolymerized form and that the neurofilament proteins were transported in an insoluble, presumably polymerized form.