Determination of Nanoparticle Size Using a Flow Particle-Tracking Method

We developed a novel method to determine the mean size of nanoparticles under flow conditions, the flow particle-tracking (FPT) method. The liquid particle counting method is commonly utilized to determine number-based size under flow conditions by converting the light scattering intensity of individual particles to size using the relationship between the size and light scattering intensity of a size standard material; however, the determined size depends strongly on the type of size standard material. In contrast, the developed FPT method can reliably determine the mean size of nanoparticles under flow conditions according to the Stokes-Einstein assumption by observing the Brownian motion of individual particles; therefore, this method does not require a calibration step using a size standard and can be applied to any type of material. To reliably size particles under flow conditions, we determined the flow velocity profile in a sample cell by extracting only the flow velocity from the particle motion. After determining the self-diffusion coefficient of each particle and subtracting the effect of the flow velocity, we successfully obtained a reliable mean size. The developed method could contribute to the application of microchannel reaction/synthesis devices using nanomaterials.

Intravenous Administration of Tacrolimus Stabilizes Control of Blood Concentration Regardless of CYP3A5 Polymorphism in Living Donor Liver Transplantation: Comparison of Intravenous Infusion and Oral Administration in Early Postoperative Period

BACKGROUND

We compared achievement rate of sufficient tacrolimus blood concentration in the early postoperative period and incidence of acute cellular rejection within 1 month after living donor liver transplantation (LDLT) between tacrolimus intravenous (IV) and oral administration groups.

METHODS

From October 2005 to November 2016, 61 LDLT patients administered tacrolimus, who could be genotyped for CYP3A5*3 and *1, were chosen from the electronic record database. The patients were then divided into the 2 groups (an IV group [n = 38] and an oral group [n = 23]). We defined patients with 1*1 or *1*3 as expressors and those with *3*3 as nonexpressors. Sufficient trough level tacrolimus blood concentration on postoperative day (POD) 3 was defined as 10-20 ng/mL.

RESULTS

Comparable concentrations were seen between the 2 groups, with mean blood concentration 13.7 ± 8.5 ng/mL in the oral group and 15.2 ± 4.3 ng/mL in the IV group. Achievement rate of sufficient tacrolimus concentration on POD 3 was significantly higher in the IV group than in oral group: 97% (37 of 38) vs 65% (15 of 23), respectively (P = .001). When we focused on achievement rate in the oral group according to CYP3A5 polymorphism, the frequency of expressors (17%) was significantly lower than that of nonexpressors (82%) (P = .016). However, in the IV group this negative influence was totally eliminated, resulting in high achievement rates regardless of CYP3A5 polymorphism. In terms of incidence of acute cellular rejection, there was no significant difference between the 2 groups (IV 32% vs oral 17%, P = .250).

CONCLUSION

IV administration of tacrolimus allowed us to obtain more stable control of blood concentration regardless of CYP3A5 genotype.

Abstract P3-08-11: The prognostic impact of retinoic acid-induced 2 (RAI2) expression in ERα-positive breast cancer patients

Background: Breast cancer cells disseminate to the bone marrow and form bone metastases in a large majority of late-stage patients. Retinoic Acid-Induced 2 (RAI2) was reported as a putative suppressor of early hematogenous dissemination of tumor cells to the bone marrow in breast cancer, particularly in estrogen receptor α (ERα)-positive breast cancer. Here, we investigated mRNA expression of RAI-2 in breast cancer patients during long-term follow-up.

Materials and methods: A total of 451 invasive breast cancer tissues was available for analysis of RAI2 mRNA using a TaqMan PCR system. We also sought correlations between clinicopathological factors and levels of RAI2 expression in these samples. The expression of markers associated with tumor-initiating capacity, such as SNAI1, SNAI2 and VIM was also analyzed. The median follow-up period was 9.0 years. Survival curves were analyzed using the Kaplan-Meier method. Cox proportional hazards regression analysis was used for univariate and multivariate analyses of prognostic values.

Results: We found positive correlations between low expression of RAI2 mRNA and shorter disease-free survival and overall survival in breast cancer patients (P=0.003, P<0.0001, respectively), which was limited to ERα-positive patients (P=0.04, P=0.0009, respectively), and not seen in ERα-negative patients (P=0.52, P=0.27, respectively). Low RAI2 mRNA levels were positively correlated with high grade, ERα-negativity and PgR negativity. Multivariate analysis indicated that low level RAI2 mRNA expression was an independent factor for survival both overall in breast cancer and in ERα-positive breast cancer patients

Multivariate analysis (ERα-positive breast cancer patients)  OS  Multivariate patientsp valueHR(95%CI)Tumor size≤2cm1390.83691 (Reference) >2cm207 1.08(0.54-2.28)Node statusNegative176<0.00011 (Reference) Positive144 4.72(2.33-10.34)Grade11240.95921 (Reference) 2•3218 0.98(0.50-2.14)RAI2 mRNA expressionhigh140<0.00011 (Reference) middle•low206 4.79(2.14-12.78)

.

Conclusion:We show that low expression of RAI2 is an independent factor predictive of a poor prognosis in ERα-positive breast cancer patients. RAI2 could be a promising candidate biomarker and therapeutic target in ERα-positive breast cancer to prevent dissemination to the bone marrow.

Citation Format: Nishikawa S, Kondo N, Endo Y, Hato Y, Hisada T, Nishimoto M, Dong Y, Okuda K, Kato H, Takahashi S, Nakanishi R, Toyama T. The prognostic impact of retinoic acid-induced 2 (RAI2) expression in ERα-positive breast cancer patients [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 P3-08-11.

Prediction of muscle strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs

INTRODUCTION

Oncological margins and prognosis are the most important factors for operative planning of soft tissue sarcomas, but prediction of postoperative function is also necessary. The purpose of this study was to predict the knee flexion strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs.

MATERIALS AND METHODS

Seventeen patients underwent knee flexor muscle resection for soft tissue sarcoma of the lower limbs between 1991 and 2015. The type of resected muscles was surveyed, knee flexion strength (ratio of affected to unaffected side) was evaluated using the Biodex System isokinetic dynamometer, and differences between the type of resected muscles were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and Short Form 8 (SF-8) were used to assess postoperative function and examine correlations with flexion strength. The cutoff value for flexion strength to predict good postoperative results was calculated by a receiver operating characteristic (ROC) curve and Fisher's exact test.

RESULTS

Median flexion strength decreased in the resection of sartorius (97.8%), gracilis (95.4%), gastrocnemius (85.2%; interquartile range (IQR): 85.0-86.2), medial hamstrings (semimembranosus and semitendinosus, 76.2%; IQR: 73.3-78.0), lateral hamstrings (long and short head of biceps femoris, 66.1%; IQR: 65.9-70.4), and bilateral hamstrings (27.3%; IQR: 26.6-31.5). A significant difference was observed between lateral and bilateral hamstrings resection (P=0.049). Flexion strength was associated with lower functional scales (MSTS score, P=0.021; TESS, P=0.008; EQ-5D, P=0.034). Satisfactory function was obtained at a flexion strength cutoff value of 65.7%, and strength remained above the cutoff value up to unilateral hamstrings resection.

DISCUSSION

Greater knee flexor muscles resection can result in functional deficits that are associated with decreased flexion strength. If continuity of unilateral hamstrings is maintained, good postoperative results can be expected.

LEVEL OF EVIDENCE

IV, retrospective study.

Live imaging of extracellular signal-regulated kinase and protein kinase A activities during thrombus formation in mice expressing biosensors based on Förster resonance energy transfer

Essentials Spatiotemporal regulation of protein kinases during thrombus formation remains elusive in vivo. Activities of protein kinases were live imaged in mouse platelets at laser-ablated arterioles. Protein kinase A was activated in the dislodging platelets at the downstream side of the thrombus. Extracellular signal-regulated kinase was activated at the core of contracting platelet aggregates.

SUMMARY

Background The dynamic features of thrombus formation have been visualized by conventional video widefield microscopy or confocal microscopy in live mice. However, owing to technical limitations, the precise spatiotemporal regulation of intracellular signaling molecule activities, which have been extensively studied in vitro, remains elusive in vivo. Objectives To visualize, by the use of two-photon excitation microscopy of transgenic mice expressing Förster resonance energy transfer (FRET) biosensors for extracellular signal-regulated kinase (ERK) and protein kinase A (PKA), ERK and PKA activities during thrombus formation in laser-injured subcutaneous arterioles. Results When a core of densely packed platelets had developed, ERK activity was increased from the basal region close to the injured arterioles. PKA was activated at the downstream side of an unstable shell overlaying the core of platelets. Intravenous administration of a MEK inhibitor, PD0325901, suppressed platelet tethering and dislodged platelet aggregates, indicating that ERK activity is indispensable for both initiation and maintenance of the thrombus. A cAMP analog, dbcAMP, inhibited platelet tethering but failed to dislodge the preformed platelet aggregates, suggesting that PKA can antagonize thrombus formation only in the early phase. Conclusion In vivo imaging of transgenic mice expressing FRET biosensors will open a new opportunity to visualize the spatiotemporal changes in signaling molecule activities not only during thrombus formation but also in other hematologic disorders.

Outcomes of grafting intrasynovial tendons of the toes to the hands in 10 patients: a preliminary report

Ten patients had intrasynovial tendon grafting harvested from the toes for secondary flexor tendon reconstruction in nine fingers and one thumb in our institutes from 2009 to 2014. These patients were followed for a mean of 15 (range: 8-36) months. The ranges of total active motion of the proximal and distal interphalangeal joints of these nine fingers were 143° (range: 108-175°) and of the metacarpophalangeal and interphalangeal joints of one thumb were 110°. In conclusion, this technique is feasible and gives a good result when successful but with a high complication rate. Level of Evidence IV.

Abstract PD4-08: Efficacy of compression therapy using surgical gloves for nanoparticle albumin-bound-paclitaxel-induced peripheral neuropathy: A phase II multicenter study by the Kamigata breast cancer study group

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse effect of many commonly used chemotherapeutic agents, including taxanes. However, there is currently no established effective prophylactic management for CIPN. Thus, we investigated the efficacy of using surgical glove (SG) compression therapy to prevent nanoparticle albumin-bound-paclitaxel (nab-PTX)-induced peripheral neuropathy.

PATIENTS AND METHODS: Patients with primary and recurrent breast cancer who received 260 mg/m2 of nab-PTX were eligible for this case-control study. The patients wore two SGs of the same size, that is, one size smaller than the size that fit, on their dominant hand for 90 minutes. They did not wear SGs on the non-dominant hand, which served as the control hand. Peripheral neuropathy was evaluated at each treatment cycle using Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 and the Patient Neurotoxicity Questionnaire (PNQ). The temperatures of each fingertip of the compression SG-protected and control hands were measured by using thermography.

RESULTS: Between August 2013 and January 2016, 43 patients were enrolled, and 42 were evaluated. As shown in Table 1, the overall occurrence of ≥grade 2 sensory and motor peripheral neuropathy according to the CTCAE was significantly lower in the SG-protected hands than in the control hands (76.1% vs. 21.4% and 57.1% vs. 26.2%, respectively, p < 0.0001). The PNQ results showed that the incidence of ≥grade 4 neuropathy was significantly higher in the control hands than in the SG-protected hands in terms of both sensory and motor neurotoxicity (p < 0.0001, Table 2). As the treatment cycles of nab-PTX increased, the mean CTCAE and PNQ grades of the control hands gradually increased. However, the SG-protected hands maintained significantly lower mean grades than the control hands over time (p < 0.0001).

No patients withdrew from this study because they could not tolerate the compression from the SGs. The mean temperature of each fingertip significantly decreased (1.42–2.60 °C) in the SG-protected hands compared to in the control hands.

CONCLUSIONS: SG compression therapy appears effective for reducing nab-PTX-induced peripheral neuropathy. The nab-PTX exposure to the peripheral nerve may be decreased because the SG decreases microvascular flow to the fingertip.

Table 1: Comparison of the overall occurrences of the different grades of peripheral neuropathy according to CTCAE version 4.0 between the compression surgical glove-protected hands and control handsCTCAE v.4.0SensoryMotorGradeSurgical GloveControlSurgical GloveControl012418712161311292411163080840000

Table 2: Changes in the overall occurrence of the Patient Neurotoxicity Questionnaire (PNQ) grade with surgical glove compression therapyPNQSensoryMotorGradeSurgical gloveControlSurgical gloveControl194209223512113717912431611050000

Citation Format: Tsuyuki S, Senda N, Kanng Y, Yamaguchi A, Yoshibayashi H, Kikawa Y, Katakami N, Kato H, Hashimoto T, Okuno T, Yamauchi A, Inamoto T. Efficacy of compression therapy using surgical gloves for nanoparticle albumin-bound-paclitaxel-induced peripheral neuropathy: A phase II multicenter study by the Kamigata breast cancer study group [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD4-08.

Significant improvement of bone mineral density and bone turnover markers by denosumab therapy in bisphosphonate-unresponsive patients

Bone mineral density (BMD) sometimes cannot be improved by long-term bisphosphonate (BP) therapy in osteoporosis (OP). This study showed that lumbar as well as hip BMD significantly increased after denosumab treatment in patients not responsive to BPs. Thus, denosumab may be a strong OP treatment option for BP-unresponsive patients.

INTRODUCTION

BMD sometimes cannot be improved by long-term BP therapy.

METHODS

We administered denosumab to osteoporotic patients with a poor response to BPs who had been taking them for 2 years or longer. Ninety-eight women with BP-poor responsive OP were enrolled in this study. Mean (standard deviation [SD]) age was 71.2 (6.9) years and mean (SD) duration of BP treatment was 59.9 (34.3) months. We distinguished BP responders from non-responders based on changes in BMD values at denosumab commencement (baseline) from 2 years beforehand.

RESULTS

There were no significant differences in age, duration of BP use, bone turnover markers, or BMD at baseline between the groups. Prior to denosumab, BMD had increased significantly in responders and decreased significantly in non-responders. Bone turnover markers had decreased significantly at 4 months of denosumab treatment (P < 0.001) and lumbar and hip BMD were significantly increased at 1 year of therapy in both groups (P < 0.001). Simple correlation coefficients were -0.337 for lumbar and -0.339 for hip BMD changes (both P = 0.001) before and after denosumab treatment. Both at the lumbar spine and hips, decreased BMD before denosumab therapy was significantly associated with an increase in BMD at 1 year of treatment (spine, t value = -3.502, P = 0.001, R = 0.113; hip, t value = -3.526, P = 0.001, R = 0.115).

CONCLUSIONS

These results suggest that denosumab may be a strong OP treatment option for BP-unresponsive patients.

Pretransplant Serum Hyaluronic Acid Can Be a Biomarker as a Prognostic Predictor in Adult-to-Adult Living Donor Liver Transplantation

OBJECTIVE

The goal of this study was to evaluate whether pretransplant serum hyaluronic acid (HA) levels can predict outcomes after adult-to-adult living donor liver transplantation (LDLT).

METHODS

In study I, 21 patients who underwent LDLT (March 2002-February 2004) were divided into 2 groups: the H-I group (HA ≥500 ng/mL; n = 12) and the L-I group (HA <500 ng/mL; n = 9). The influence of pretransplantation HA levels on short-term surgical outcome was investigated. In study II, 77 LDLT patients (May 2004-December 2014) were also divided into 2 groups: the H-II group (HA ≥500 ng/mL; n = 40) and the L-II group (HA <500 ng/mL; n = 37). We compared long-term survival and investigated prognostic factors.

RESULTS

In study I, HA levels significantly decreased after LDLT, and those in the H-I group were significantly higher compared with the L-I group at 1, 3, 5, and 7 days after LDLT. There were significant differences in postoperative peak total bilirubin levels (H-I vs L-I, 17.2 vs 6.2 mg/dL; P = .013), peak ascitic fluid volume (1327 vs 697 mL/d; P = .005), and the hepatocyte growth factor levels at 3 days after LDLT (1879 vs 1092 pg/mL; P = .03). In study II, the 1- and 5-year survival rates were significantly lower in the H-II group than in the L-II group (H-II vs L-II, 65.0% and 48.5% vs 86.5% and 80.8%; P = .004). In multivariate analysis, significant prognostic factors were preoperative HA ≥500 ng/mL (P = .004) and graft to recipient body weight ratio <0.8 (P = .042).

CONCLUSIONS

Preoperative HA level can be a prognostic risk factor. Patients with high HA levels are vulnerable and should be carefully managed after LDLT.

Discontinuation of Hepatitis B Immunoglobulin by Long-term Hepatitis B Vaccine Inoculation in Preventing Hepatitis B Recurrence After Liver Transplantation

INTRODUCTION

For the patients undergoing liver transplantation for hepatitis B virus (HBV)-related diseases, hepatitis B immunoglobulin (HBIG) should be administered to prevent reinfection. Because HBIG is highly expensive and a blood product, an alternative strategy using HBV vaccination has been made in an attempt to discontinue use of HBIG. The aim of this study was to evaluate the impact of long-term HBV vaccination for discontinuation of HBIG, paying attention to the status of active immunization using T-cell proliferation assay.

PATIENTS AND METHODS

Among the 144 recipients who underwent liver transplantation in our hospital, 16 had HBV-related liver diseases; the 14 patients who had received vaccination were subjects in our study. To evaluate the status of active immunization, T-cell proliferation was examined by counting the number of T cells after adding HBV vaccine to the culture supernatant of T cells, and tumor necrosis factor α and interferon γ were measured in the culture supernatant.

RESULTS

The ratio of male/female was 13/1 (median age: 55 years; range: 37 years to 67 years). The median follow-up time was 102 months (range: approximately 14 months to 148 months). All 14 patients were free of HBV recurrence. HBIG-free status could be achieved in 9 patients (64.3%) during the treatment period for more than 50 months after beginning of HBV vaccination, of whom 5 (35.7%) became HBV vaccine-free. T-cell proliferation was confirmed by fact that the stimulation index ranged from 2.34 to 5.2 in the patients who were HBIG-free.

CONCLUSION

Long-term HBV vaccination after LT is a useful and effective treatment in preventing HBV recurrence, allowing the discontinuation of HBIG treatment.

D-MELD, the Product of Donor Age and Preoperative MELD, Predicts Surgical Outcomes After Living Donor Liver Transplantation, Especially in the Recipients With HCV-positive and Smaller Grafts

BACKGROUND

Appropriate donor-recipient match has not been explored well in living-donor liver transplantation (LDLT) unlike deceased-donor liver transplantation. In this study, we evaluate the donor-recipient match using D-MELD (donor age × recipient Modified for End-stage Liver Disease [MELD] score) as a predictor of surgical outcomes in LDLT, paying attention to graft size and hepatitis C virus (HCV) status.

PATIENT AND METHODS

The 120 consecutive recipients who received adult-to-adult LDLT from March 2002 to December 2014 were divided into the two groups according to D-MELD score: D-MELD <1000 (low-D-MELD: n = 101) and D-MELD ≥1000 (high-D-MELD: n = 19).

RESULTS

The 90-day mortality rate was significantly higher in the high-DM group than in low-DM group: 36.8% versus 14.9% (P = .046). In the HCV-positive recipients, the 90-day mortality rate was significantly higher in high-DM group (n = 6) than in low-DM group (n = 37): 66.7% versus 13.5% (P = .012), and the 3-year survival rate was significantly lower in high-DM group than in the low-DM group: 33.3% versus 56.8% (P = .01). In the recipients with left graft, the 90-day mortality rate was significantly higher in the high-DM group (n = 8) than in the low-DM group (n = 41): 50% versus 14.6% (P = .044), and total bilirubin level on postoperative day 14 was significantly higher in the high-DM group than in the low-DM group: 17.4 mg/dL versus 9.2 mg/dL (P = .018).

CONCLUSIONS

It was clarified that D-MELD could predict early and long-term surgical outcomes in the recipients who were HCV-positive and who had smaller grafts.