<Emphasis Type="Italic">nab</Emphasis>-Paclitaxel Plus Gemcitabine Versus Gemcitabine in Patients with Metastatic Pancreatic Adenocarcinoma: Canadian Subgroup Analysis of the Phase 3 MPACT Trial

Introduction

The phase III MPACT trial in patients with metastatic pancreatic cancer (MPC) demonstrated superior efficacy of nab-paclitaxel (nab-P) plus gemcitabine (Gem) compared with Gem monotherapy, including the primary endpoint of overall survival (OS; median 8.7 vs. 6.6 months; hazard ratio [HR] 0.72; P < 0.001). A significant treatment difference favoring nab-P + Gem over Gem was observed for OS in patients treated in North America. The majority of patients were from the US (88%) with only 12% from Canada. Healthcare systems and treatment patterns are different between the 2 countries, and there is limited published information on outcomes of Canadian patients treated with first-line nab-P + Gem. This analysis evaluated efficacy and safety outcomes in Canadian patients in the MPACT trial.

Methods

Treatment-naive patients with MPC (N = 861) received either nab-P 125 mg/m² + Gem 1000 mg/m² on days 1, 8, and 15 every 4 weeks or Gem 1000 mg/m² weekly for the first 7 of 8 weeks (cycle 1) and then on days 1, 8, and 15 every 4 weeks (cycle ≥2).

Results

The MPACT trial enrolled 63 patients in Canada. Baseline characteristics were well balanced and comparable with those of the intent-to-treat population. Both OS (median 11.9 vs. 7.1 months; HR 0.76; P = 0.373) and progression-free survival (median 7.2 vs. 5.2 months; HR 0.65; P = 0.224) were numerically longer and overall response rate (27% vs. 17%; P = 0.312) was numerically higher with nab-P + Gem vs. Gem. The most common grade ≥3 adverse events with nab-P + Gem vs. Gem were neutropenia (22% vs. 10%), fatigue (34% vs. 33%), and neuropathy (25% vs. 0%).

Conclusion

This subanalysis confirmed that nab-P + Gem is an efficacious treatment option and has a manageable safety profile in patients with MPC treated in Canada.

Trial registration

ClinicalTrials.gov identifier, NCT00844649.

Funding

Celgene Corporation, Summit, NJ, USA.

     

Bioluminescence Imaging of Colonization and Clearance Dynamics of <Emphasis Type="Italic">Brucella Suis</Emphasis> Vaccine Strain S2 in Mice and Guinea Pigs

Purpose

The goal of this study was to develop a plasmid-based lux bio-reporter for use to obtain in vivo images of Brucella suis vaccine strain 2 (B.suis S2) infection with high resolution and good definition.

Procedures

The pBBR-lux (pBBR1MCS-2-lxCDABE) plasmid that carries the luxCDABE operon was introduced into B. suis S2 by electroporation yielding B. suis S2-lux. The spatial and temporal transit of B. suis S2 in mice and guinea pigs was monitored by bioluminescence imaging.

Results

The plasmid pBBR-lux is stable in vivo and does not appear to impact the virulence or growth of bacteria. This sensitive luciferase reporter could represent B. suis S2 survival in real time. B. suis S2 mainly colonized the lungs, liver, spleen, and uterus in mice and guinea pigs as demonstrated by bioluminescence imaging.

Conclusion

The plasmid-based lux bioreporter strategy can be used to obtain high resolution in vivo images of B. suis S2 infection in mice and guinea pigs.

     

<Emphasis Type="Italic">Staphylococcus aureus</Emphasis> Evasion of Host Immunity in the Setting of Prosthetic Joint Infection: Biofilm and Beyond

Purpose of Review

The incidence of complications from prosthetic joint infection (PJI) is increasing, and treatment failure remains high. We review the current literature with a focus on Staphylococcus aureus pathogenesis and biofilm, as well as treatment challenges, and novel therapeutic strategies.

Recent Findings

S. aureus biofilm creates a favorable environment that increases antibiotic resistance, impairs host immunity, and increases tolerance to nutritional deprivation. Secreted proteins from bacterial cells within the biofilm and the quorum-sensing agr system contribute to immune evasion. Additional immunoevasive properties of S. aureus include the formation of staphylococcal abscess communities (SACs) and canalicular invasion. Novel approaches to target biofilm and increase resistance to implant colonization include novel antibiotic therapy, immunotherapy, and local implant treatments.

Summary

Challenges remain given the diverse mechanisms developed by S. aureus to alter the host immune responses. Further understanding of these processes should provide novel therapeutic mechanisms to enhance eradication after PJI.

     

Effect of sinus rhythm restoration on markers of thrombin generation in atrial fibrillation

Background

Atrial fibrillation (AF) confers a hypercoagulable state; however, it is not clear whether restoration of sinus rhythm is associated with normalisation of markers of thrombogenesis. We studied the impact of sustained sinus rhythm on prothrombotic markers, and their predictive abilities in foreseeing rhythm outcome after cardioversion.

Methods

In a double blind, placebo-controlled study, 171 patients referred for electrical cardioversion of persistent AF were randomised to receive candesartan or placebo for 3-6 weeks before and 6 months after cardioversion. Endogenous thrombin potential (ETP), prothrombin fragment 1?+?2 (F1?+?2) and D-dimer were measured before cardioversion and at end of study. These markers were also measured in a reference group comprising 49 subjects without AF.

Results

The markers remained unchanged in those 28 patients who maintained sinus rhythm. Discontinuation of warfarin treatment in a subset of 13 low-risk patients in sinus rhythm was associated with significantly higher levels of D-dimer and F1?+?2 compared to the reference group; D-dimer (456 ng/mL (276, 763) vs. 279 ng/mL (192, 348), p?=?0.002) and F1?+?2 (700 pmol/L (345, 845) vs. 232 pmol/L (190, 281), p?<?0.001). None of the markers were associated with rhythm outcome after electrical cardioversion.

Conclusions

Sustained sinus rhythm for 6 months after cardioversion for AF had no impact on ETP, F1?+?2 or D-dimer levels. Discontinuation of warfarin in low-risk patients with sustained sinus rhythm was associated with significantly higher levels of D-dimer and F1?+?2 compared to the reference group. Our results suggest persistent hypercoagulability in AF patients despite long-term maintenance of sinus rhythm.

Trial registration

The CAPRAF study was registered at clinicaltrials.gov (NCT00130975) in August 2005.

     

Detection of Enzyme Activity and Inhibition during Studies in Solution, <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> with CatalyCEST MRI

Purpose

The detection of enzyme activities and evaluation of enzyme inhibitors have been challenging with magnetic resonance imaging (MRI). To address this need, we have developed a diamagnetic, nonmetallic contrast agent and a protocol known as catalyCEST MRI that uses chemical exchange saturation transfer (CEST) to detect enzyme activity as well as enzyme inhibition.

Procedures

We synthesized a diamagnetic MRI contrast agent that has enzyme responsive and enzyme unresponsive CEST signals. We tested the ability of this agent to detect the activity of kallikrein 6 (KLK6) in biochemical solutions, in vitro and in vivo, with and without a KLK6 inhibitor.

Results

The agent detected KLK6 activity in solution and also detected KLK6 inhibition by antithrombin III. KLK6 activity was detected during in vitro studies with HCT116 colon cancer cells, relative to the detection of almost no activity in a KLK6-knockdown HCT116 cell line and HCT116 cells treated with antithrombin III inhibitor. Finally, strong enzyme activity was detected within an in vivo HCT116 tumor model, while lower enzyme activity was detected in a KLK6 knockdown tumor model and in the HCT116 tumor model treated with antithrombin III inhibitor. In all cases, comparisons of the enzyme responsive and enzyme unresponsive CEST signals were critical for the detection of enzyme activity.

Conclusions

This study has established that catalyCEST MRI with an exogenous diaCEST agent can evaluate enzyme activity and inhibition in solution, in vitro and in vivo.

     

Quantitative [<Superscript>18</Superscript>F]FMISO PET Imaging Shows Reduction of Hypoxia Following Trastuzumab in a Murine Model of HER2+ Breast Cancer

Purpose

Evaluation of [¹⁸F]fluoromisonidazole ([¹⁸F]FMISO)-positron emission tomography (PET) imaging as a metric for evaluating early response to trastuzumab therapy with histological validation in a murine model of HER2+ breast cancer.

Procedures

Mice with BT474, HER2+ tumors, were imaged with [¹⁸F]FMISO-PET during trastuzumab therapy. Pimonidazole staining was used to confirm hypoxia from imaging.

Results

[¹⁸F]FMISO-PET indicated significant decreases in hypoxia beginning on day 3 (P?<?0.01) prior to changes in tumor size. These results were confirmed with pimonidazole staining on day 7 (P?<?0.01); additionally, there was a significant positive linear correlation between histology and PET imaging (r ² ?=?0.85).

Conclusions

[¹⁸F]FMISO-PET is a clinically relevant modality which provides the opportunity to (1) predict response to HER2+ therapy before changes in tumor size and (2) identify decreases in hypoxia which has the potential to guide subsequent therapy.

     

Novel Approach to Repeated Arterial Blood Sampling in Small Animal PET: Application in a Test-Retest Study with the Adenosine A1 Receptor Ligand [<Superscript>11</Superscript>C]MPDX

Purpose

Small animal positron emission tomography (PET) can be used to detect small changes in neuroreceptor availability. This often requires rapid arterial blood sampling. However, current catheterization procedures do not allow repeated blood sampling. We have developed a procedure which allows arterial sampling on repeated occasions in the same animal.

Procedures

Eleven male Wistar rats were two times catheterized via a superficial branch of a femoral artery and scanned with [¹¹C]MPDX and blood sampling. PET images were co-registered to a magnetic resonance imaging (MRI) template. Regional tracer distribution volumes (V _T) in the brain were calculated by the Logan analysis. The procedure was repeated after 1 week.

Results

Surgery was successful in 90 % of the cases, and discomfort was minor. The V _T data showed small differences between test and retest, low between subject variability, and a strong agreement between and within subjects.

Conclusion

Repeated quantitative imaging with a high reproducibility is possible with this approach.

     

Superselective transcatheter arterial embolization in patients with acute peripancreatic bleeding complications: review of 44 cases

Purpose

To evaluate the efficacy of superselective transcatheter arterial embolization (TAE) in the treatment of acute peripancreatic bleeding complications.

Methods

During a 9-year period, 44 patients with acute bleeding of the peripancreatic arteries underwent TAE in our institution. Thirty-eight patients were treated using microcatheters and 6 patients with a diagnostic catheter. Embolic agents included coils (n = 38), polyvinyl alcohol (PVA) particles (n = 2), isobutyl cyanoacrylate (n = 2), coils plus PVA particles (n = 1), and coils plus isobutyl cyanoacrylate (n = 1). Outcome measures included technical success, clinical success, and the rate of complications.

Results

Identified bleeding sources included gastroduodenal artery (n = 14), splenic artery (n = 9), pancreaticoduodenal artery (n = 6), common hepatic artery (n = 5), superior mesenteric artery branches (n = 4), proper hepatic artery (n = 3), and dorsal/transverse pancreatic artery (n = 3). Technical success with effective control of active bleeding was achieved in 41/44 patients (93 %). Clinical success attributed to TAE alone was documented in 40/44 patients (91 %). The rate of major complications was 2 % including death in one patient.

Conclusions

Superselective TAE allows effective, minimally invasive control of acute peripancreatic bleeding complications with a low rate of therapeutically relevant complications.

     

3D Boolean operations in virtual surgical planning

Purpose

Boolean operations in computer-aided design or computer graphics are a set of operations (e.g. intersection, union, subtraction) between two objects (e.g. a patient model and an implant model) that are important in performing accurate and reproducible virtual surgical planning. This requires accurate and robust techniques that can handle various types of data, such as a surface extracted from volumetric data, synthetic models, and 3D scan data.

Methods

This article compares the performance of the proposed method (Boolean operations by a robust, exact, and simple method between two colliding shells (BORES)) and an existing method based on the Visualization Toolkit (VTK).

Results

In all tests presented in this article, BORES could handle complex configurations as well as report impossible configurations of the input. In contrast, the VTK implementations were unstable, do not deal with singular edges and coplanar collisions, and have created several defects.

Conclusions

The proposed method of Boolean operations, BORES, is efficient and appropriate for virtual surgical planning. Moreover, it is simple and easy to implement. In future work, we will extend the proposed method to handle non-colliding components.

     

Potential Effect of Prolonged Sevoflurane Anesthesia on the Kinetics of [<Superscript>11</Superscript>C]Raclopride in Non-human Primates

Purpose

Positron emission tomography (PET) in non-human primates (NHP) is commonly performed under anesthesia, with sevoflurane being a widely used inhaled anesthetic. PET measurement in NHP can be repeated, and a difference in radioligand kinetics has previously been observed between the first and second PET measurement on the same day using sevoflurane anesthesia. In this study, we evaluated the effect of prolonged sevoflurane anesthesia on kinetics and binding potential (BP_ND) of [¹¹C]raclopride in NHP.

Procedures

Three cynomolgus monkeys underwent two to three PET measurements with [¹¹C]raclopride under continuous sevoflurane anesthesia on the same day. The concentration of sevoflurane was adjusted according to the general conditions and safety parameters of the NHP. Time to peak (TTP) radioactivity in the striatum was estimated from time-activity curves (TACs). The BP_ND in the striatum was calculated by the simplified reference tissue model using the cerebellum as reference region.

Results

In each NHP, the TTP became shorter in the later PET measurements than in the first one. Across all measurements (n = 8), concentration of sevoflurane correlated with TTP (Spearman’s ρ = ? 0.79, p = 0.03), but not with BP_ND (ρ = ? 0.25, p = 0.55).

Conclusions

These data suggest that sevoflurane affects the shape of TACs but has no evident effect on BP_ND in consecutive PET measurements.

     

Validation trial for efficacy of ultrasonographic measurement method to predict ascitic volume using virtual ultrasonography

Purpose

The aim of this study was to clarify whether ultrasound quantitative methods were positively correlated with volume of ascites evaluated by whole abdominopelvic CT.

Methods

Sixty-eight patients with cirrhotic ascites were retrospectively analyzed. First, to confirm that virtual ultrasonography (VUS) is an alternative method to conventional ultrasound, 22 patients underwent both conventional ultrasonography and VUS. Second, the efficacy of US quantitative methods (3-point method, 4-point method, 5-point method, and Matsumoto’s method) was confirmed by VUS in 68 patients. We assessed whether the ascites volume predicted by VUS corresponded with that calculated by 3D-CT. Of the 68 patients, 23 patients were analyzed before and after administration of tolvaptan.

Results

The predictive volumes calculated by VUS were remarkably relative to those yielded by conventional US. Correlations between exact volume and those measured by VUS were significantly high (3-point method: r?=?0.882, p?<?0.001; 4-point method: r?=?0.797, p?<?0.001; 5-point method: r?=?0.836, p?<?0.001; Matsumoto’s method: r?=?0.453, p?<?0.001). Correlations between decreasing volume on 3D-CT and that measured by VUS were also significantly high in patients with administration of tolvaptan.

Conclusion

Ascites volume measured by ultrasound was effective, especially the 3-point and 5-point methods. It was useful to assess the efficacy of diuretics in cirrhotic patients.

     

A Randomized Trial Investigating the Pharmacokinetics,Pharmacodynamics, and Safety of Subcutaneous Semaglutide Once-Weekly in Healthy Male Japanese and Caucasian Subjects

Introduction

Semaglutide is a glucagon-like peptide-1 analogue for once-weekly subcutaneous treatment of type 2 diabetes. This trial compared the pharmacokinetics, pharmacodynamics, and safety of semaglutide in Japanese and Caucasian subjects.

Methods

In this single-center, double-blind, parallel-group, 13-week trial, 44 healthy male subjects (22 Japanese, 22 Caucasian) were randomized within each race to semaglutide 0.5 mg (n = 8), 1.0 mg (n = 8), placebo 0.5 mg (n = 3) or 1.0 mg (n = 3). The primary endpoint was semaglutide exposure at steady state [area under the curve (AUC_0–168h)].

Results

Steady-state exposure of semaglutide was similar for both populations: AUC_0–168h estimated race ratio (ERR), Japanese/Caucasian: 0.5 mg, 1.06; 1.0 mg, 0.99; maximum concentration (C_max) ERR: 0.5 mg, 1.06; 1.0 mg, 1.02. Exposure after the first dose (0.25 mg) was slightly higher in Japanese versus Caucasian subjects (AUC_0–168h ERR 1.11; C_max ERR 1.14). Dose-dependent increases in AUC_0–168h and C_max occurred in both populations. Accumulation was as expected, based on the half-life (t_1/2, ~ 1 week) and dosing interval of semaglutide. Significant body weight reductions were observed with semaglutide 0.5 mg and 1.0 mg in Japanese (both p ≤ 0.05) and Caucasian (both p ≤ 0.05) subjects versus placebo. No new safety issues were identified.

Conclusions

The pharmacokinetic, pharmacodynamic, and safety profiles of semaglutide were similar in Japanese and Caucasian subjects, suggesting that no dose adjustment is required for the clinical use of semaglutide in Japanese subjects.

Funding

Novo Nordisk A/S, Denmark.

Trial registration

ClinicalTrials.gov identifier NCT02146079. Japanese trial registration number JapicCTI-142550.

     

Erythropoietin and renin as biological markers in critically ill patients

Introduction

During sepsis the endocrine, immune and nervous systems elaborate a multitude of biological responses. Little is known regarding the mechanisms responsible for the final circulating erythropoietin (EPO) and renin levels in septic shock. The aim of the present study was to assess the role of EPO and renin as biological markers in patients with septic shock.

Methods

A total of 44 critically ill patients with septic shock were evaluated.

Results

Nonsurvivors had significantly higher serum EPO levels than did survivors on admission (median [minimum–maximum]; 61 [10–602] versus 20 [5–369]). A negative relationship between serum EPO and blood haemoglobin concentrations was observed in the survivor group (r = -0.61; P < 0.001). In contrast, in the nonsurvivors the serum EPO concentration was independent of the blood haemoglobin concentration. Furthermore, we observed significant relationships between EPO concentration and lactate (r = 0.5; P < 0.001), arterial oxygen tension/fractional inspired oxygen ratio (r = -0.41; P < 0.005), arterial pH (r = -0.58; P < 0.001) and renin concentration (r = 0.42; P < 0.005). With regard to renin concentration, significant correlations with lactate (r = 0.52; P < 0.001) and arterial pH (r = -0.33; P < 0.05) were observed.

Conclusion

Our findings show that EPO and renin concentrations increased in patients admitted to the intensive care unit with septic shock. Renin may be a significant mediator of EPO upregulation in patients with septic shock. Further studies regarding the regulation of EPO expression are clearly warranted.

     

Comparison of clinical MRI liver iron content measurements using signal intensity ratios, <Emphasis Type="Italic">R</Emphasis><Subscript>2</Subscript> and <Emphasis Type="Italic">R</Emphasis><Subscript>2</Subscript>*

Purpose

To compare three types of MRI liver iron content (LIC) measurement performed in daily clinical routine in a single center over a 6-year period.

Methods

Patients undergoing LIC MRI-scans (1.5T) at our center between January 1, 2008 and December 31, 2013 were retrospectively included. LIC was measured routinely with signal intensity ratio (SIR) and MR-relaxometry (R ₂ and R ₂*) methods. Three observers placed regions-of-interest. The success rate was the number of correctly acquired scans over the total number of scans. Interobserver agreement was assessed with intraclass correlation coefficients (ICC) and Bland–Altman analysis, correlations between LIC_SIR, R ₂, R ₂*, and serum values with Spearman’s rank correlation coefficient. Diagnostic accuracies of LIC_SIR, R ₂ and serum transferrin, transferrin-saturation, and ferritin compared to increased R ₂* (≥44 Hz) as indicator of iron overload were assessed using ROC-analysis.

Results

LIC MRI-scans were performed in 114 subjects. SIR, R ₂, and R ₂* data were successfully acquired in 102/114 (89%), 71/114 (62%), and 112/114 (98%) measurements, with the lowest success rate for R ₂. The ICCs of SIR, R ₂, and R ₂* did not differ at 0.998, 0.997, and 0.999. R ₂ and serum ferritin had the highest diagnostic accuracies to detect elevated R ₂* as mark of iron overload.

Conclusions

SIR and R ₂* are preferable over R ₂ in terms of success rates. R ₂*’s shorter acquisition time and wide range of measurable LIC values favor R ₂* over SIR for MRI-based LIC measurement.

     

Correlation between the combination of apparent integrated backscatter–spectral centroid shift and bone mineral density

Purpose

To introduce a new diagnostic parameter: the linear combination of apparent integrated backscatter and spectral centroid shift.

Methods

Ultrasonic backscatter measurements were performed at the calcanei of 1262 volunteers in vivo. The hip and spine bone mineral densities of the volunteers were measured using dual X-ray absorptiometry. The apparent integrated backscatter and spectral centroid shift were calculated. A new diagnostic parameter, i.e., the linear combination of apparent integrated backscatter and spectral centroid shift, was introduced and its correlation to bone mineral density was analyzed.

Results

The results show that the combination of apparent integrated backscatter and spectral centroid shift is significantly correlated to bone mineral density (R = 0.73–0.84, n = 1262, p < 0.05), and that this correlation is more significant than the correlation between the apparent integrated backscatter and bone mineral density or the correlation between spectral centroid shift and bone mineral density (R = 0.48–0.69, p < 0.05).

Conclusion

The combination of apparent integrated backscatter and spectral centroid shift can provide the complementary information of attenuation of the two parameters and predict more information about cancellous bone, and may be employed to assess cancellous bone status.

     

Predictive Value of Asphericity in Pretherapeutic [<Superscript>111</Superscript>In]DTPA-Octreotide SPECT/CT for Response to Peptide Receptor Radionuclide Therapy with [<Superscript>177</Superscript>Lu]DOTATATE

Purpose

The purpose of this study was to assess the value of the spatial heterogeneity of somatostatin receptor (SSR) volume, quantified as asphericity (ASP), and to predict response to peptide receptor radionuclide therapy (PRRT) in patients with metastatic gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN).

Procedures

From June 2011 to May 2013, patients suffering from GEP-NEN who underwent pretherapeutic [¹¹¹In-DTPA⁰]octreotide scintigraphy (Octreoscan®) prior to [¹⁷⁷Lu-DOTA⁰-Tyr³]octreotate ([¹⁷⁷Lu]DOTATATE)-PRRT were enrolled in this retrospective evaluation. SSR expression in 20 NEN patients was qualitatively and quantitatively assessed using the Krenning score, the metastasis to liver uptake ratio (M/L ratio), and ASP at baseline. Response to PRRT was evaluated based on lesions, which were classified as responding lesions (RL) and non-responding lesions (NRL) after 4- and 12-month follow-ups. The values of the Krenning score, M/L ratio, and ASP for response prediction were compared by using the Mann-Whitney U test, Kruskal-Wallis test, and receiver operating characteristic (ROC) curves.

Results

Seventy-seven metastases (liver, n = 40; lymph node, n = 24; bone, n = 11; pancreas, n = 2) showed SSR expression. A higher ASP level was significantly associated with poorer response at both time points. ROC analyses revealed the highest area under the curve (AUC) for discrimination between RL and NRL for ASP after 4 months (AUC 0.97; p = 0.019) and after 12 months (AUC 0.96; p < 0.001), followed by the Krenning score (AUC 0.74; p = 0.082 and AUC 0.85; p < 0.001, respectively) and M/L ratio (AUC 0.77; p = 0.107 and AUC 0.82; p < 0.001). The optimal cutoff value for ASP was 5.12 % (sensitivity, 90 %; specificity, 93 %).

Conclusion

Asphericity of SSR-expressing lesions in pretherapeutic single-photon emission computed tomography with integrated computed tomography (SPECT/CT) is a promising parameter for predicting response to PRRT in gastroenteropancreatic neuroendocrine neoplasms.

     

Safety and tolerability of a single administration of AR-301, a human monoclonal antibody,in ICU patients with severe pneumonia caused by <Emphasis Type="Italic">Staphylococcus aureus</Emphasis>: first-in-human trial

Purpose

Hospital-acquired bacterial pneumonia (HABP) is a critical concern in hospitals with ventilator-associated bacterial pneumonia (VABP) remaining the most common infection in the ICU, often due to Staphylococcus aureus, an increasingly difficult to treat pathogen. Anti-infective monoclonal antibodies (mAb) may provide new, promising treatment options. This randomized, double-blinded, placebo-controlled study aimed at assessing the safety and pharmacokinetics of AR-301, an S. aureus alpha toxin-neutralizing mAb, and exploring its clinical and microbiologic outcomes when used adjunctively with standard-of-care antibiotics.

Methods

Eligibility in this trial required microbiologically confirmed severe S. aureus pneumonia, including HABP, VABP or CABP, treated in the ICU and an APACHE II score ≤?30. Standard-of-care antibiotics selected by the investigators were administered to all patients in the study following clinical and microbiologic confirmation of S. aureus pneumonia. Adjunctive treatment of AR-301 was to start <?36 h after onset of severe pneumonia. AR-301 was administered to four sequentially ascending dose cohorts. The placebo cohort received antibiotics and a placebo buffer. Clinical outcomes were adjudicated by a blinded committee. S. aureus eradication was declared based on a negative follow-up culture and presumed to be negative when no culture was obtained in the presence of clinical improvement.

Results

Thirteen ICUs enrolled 48 patients, with pneumonia attributable to MRSA in six subjects. The study drug displayed a favorable safety profile: Of 343 AEs reported, 8 (2.3%) were deemed related, none serious. In a post hoc subgroup analysis of VABP patients receiving AR-301, ventilation duration was shorter for AR-301-treated patients compared with the placebo group. Overall, there was a trend toward a better and faster microbiologic eradication at day 28. The PK profile of AR-301 is consistent with that of a human IgG1 mAb, with a plasma half-life of about 25 days.

Conclusions

Adjunctive treatment of severe S. aureus HABP with anti-staphylococcal mAbs appears feasible and suggests some clinical benefits, but larger randomized studies are needed to better define its safety and efficacy.

     

Bioluminescence Imaging for Monitoring miR-200c Expression in Breast Cancer Cells and its Effects on Epithelial-Mesenchymal Transition Progress in Living Animals

Purpose

Dysregulation of microRNAs (miRNAs) are not only involved in the formation of malignant tumors but also in the processes of differentiation and aggressiveness. However, current methods for detecting miRNA expression have major disadvantages, such as being invasive and non-reproducible. The epithelial-mesenchymal transition (EMT) has been implicated as a pivotal event in the metastasis, stemness, and chemoresistance of malignant tumors.

Procedures

In our study, we constructed a new reporter gene, Luc2/tdT_miR200c_3TS, to examine the in vitro and in vivo expression of miR-200c, an EMT-associated miRNA. Quantitative real-time PCR was used to measure the expression levels of miR-200c and EMT-related mRNA, and luciferase assay and bioluminescence imaging were used to measure the luciferase activities in vitro and in vivo, respectively.

Results

We found that the expression level of miR-200c was negatively associated with cell migration and invasion. Luciferase activities were regulated by the differential expression levels of miR-200c and EMT process.

Conclusions

Our results demonstrate that Luc2/tdT_miR200c_3TS may be a useful tool for monitoring the expression level of miR-200c at both the cellular level and in living animals, thereby providing a potential high-throughput approach for anticancer drug screening.

     

The usefulness of a computer-aided diagnosis scheme for improving the performance of clinicians to diagnose non-mass lesions on breast ultrasonographic images

Purpose

The purpose of this study was to evaluate the usefulness of a computer-aided diagnosis (CAD) scheme for improving the performance of clinicians to diagnose non-mass lesions appearing as hypoechoic areas on breast ultrasonographic images.

Methods

The database included 97 ultrasonographic images with hypoechoic areas: 48 benign cases [benign lesion with benign mammary tissue or fibrocystic disease (n = 20), fibroadenoma (n = 11), and intraductal papilloma (n = 17)] and 49 malignant cases [ductal carcinoma in situ (n = 17) and invasive ductal carcinoma (n = 32)]. Seven clinicians, three expert breast surgeons, and four general surgeons participated in the observer study. They were asked their confidence level concerning the possibility of malignancy in all 97 cases with and without the use of the CAD scheme. Receiver operating characteristic (ROC) analysis was performed to evaluate the usefulness of the CAD scheme.

Results

The areas under the ROC curve (AUC) improved for all observers when they used the CAD scheme and increased from 0.649 to 0.783 (P = 0.0167). Notably, the AUC for the general surgeon group increased from 0.625 to 0.793 (P = 0.045).

Conclusions

This study showed that the performance of clinicians to diagnose non-mass lesions appearing as hypoechoic areas on breast ultrasonographic images was improved by the use of a CAD scheme.