Biophysical analysis of gelatin and PLGA nanoparticle interactions with complex biomimetic lung surfactant models

Biocompatible materials are increasingly used for pulmonary drug delivery, and it is essential to understand their potential impact on the respiratory system, notably their effect on lung surfactant, a monolayer of lipids and proteins, responsible for preventing alveolar collapse during breathing cycles. We have developed a complex mimic of lung surfactant composed of eight lipids mixed in ratios reported for native lung surfactant. A synthetic peptide based on surfactant protein B was added to better mimic the biological system. This model was used to evaluate the impact of biocompatible gelatin and poly(lactic-co-glycolic acid) nanoparticles. Surface pressure–area isotherms were used to assess lipid packing, film compressibility and stability, whereas the lateral organization was visualized by Brewster angle microscopy. Nanoparticles increased film fluidity and altered the monolayer collapse pressure. Bright protruding clusters formed in their presence indicate a significant impact on the lateral organization of the surfactant film. Altogether, this work indicates that biocompatible materials considered to be safe for drug delivery still need to be assessed for their potential detrimental impact before use in therapeutic applications

Biodegradable nanoparticles drastically alters lateral organization of lung surfactant lipid- peptide model system.

Robotic versus open hemihepatectomy: a propensity score-matched study

BACKGROUND

Minimally invasive approach has been increasingly applied in liver resection. However, laparoscopic major hepatectomy is technically demanding and is practiced only in expert centers around the world. Conversely, use of robot may help to overcome the difficulty and facilitate major hepatectomy.

METHODS

Between September 2010 and March 2019, 151 patients received robotic hepatectomy for various indications in our center. 36 patients received robotic hemihepatectomy: 26 left hepatectomy and 10 right hepatectomy. During the same period, 737 patients received open hepatectomy and out of these, 173 patients received open hemihepatectomy. A propensity score-matched analysis was performed in a 1:1 ratio.

RESULTS

After matching, there were 36 patients each in the robotic and open group. The two groups were comparable in demographic data, type of hemihepatectomy, underlying pathology, size of tumor, and background cirrhosis. Conversion was needed in 3 patients (8.3%) in the robotic group. There was no operative mortality. The operative blood loss and resection margin were similar. Though not significantly different, there was a higher rate of complications in the robotic group (36.1% vs. 22.2%) and this difference was mostly driven by higher intra-abdominal collection (16.7% vs. 5.6%) and bile leak (5.6% vs. 2.8%). Operative time was significantly longer (400.8 ± 136.1 min vs 255.4 ± 74.4 min, P < 0.001) but the postoperative hospital stay was significantly shorter (median 5 days vs 6.5 days, P = 0.040) in the robotic group. When right and left hepatectomy were analyzed separately, the advantage of shorter hospital stay remained in left but not right hepatectomy. For patients with hepatocellular carcinoma, there was no difference between the two groups in 5-year overall and disease-free survival.

CONCLUSION

Compared with the open approach, robotic hemihepatectomy has longer operation time but shorter hospital stay. Thus, use of robot is feasible and effective in hemihepatectomy with the benefit of shorter hospital stay.

Abstract 3911: High-throughput screening of patient-derived HCC organoids for drug discovery

Current in vitro models of primary liver cancer insufficiently recapitulates the tumor heterogeneity and pathophysiology of the original patient's tumor. This significantly hinders translational studies and often leads to the high rate of clinical trial attrition and poor patient response. Recent technological advances in organoid culture methods have been reported to overcome these limitations. Our group has successfully established 3 patient-derived HCC tumor organoids that closely recapitulate the patient's pathophysiology. Conventional short-term monolayer culture of the same 3 tumors as well as 3 non-tumoral adjacent liver and 3 normal liver organoids were established and compared with 5 HCC cell lines from ATCC for their drug response profiles. Subsequent drug screening was performed using a panel of 100 drugs, of which 70 are FDA-approved for either HCC or other cancers, as well as 30 pipeline compounds targeting frequently mutated pathways in HCC. We found that our screening pipeline could achieve robust z' scores and reproducible data points with technical and biological replicates. Principal component analysis of Total Area under curve (AUC) values show distinct and progressive changes between Normal Liver, Non-tumoral adjacent liver, and Tumor organoids. Upon comparison with HCC cell lines Hep3B, HepG2, Huh7, SNU398 and PLC5, we found HCC patient-derived short term cultures, particularly organoids have more diverse drug sensitivity profiles and may be a better indicator of patient heterogeneity. Interestingly, FDA-approved drugs for HCC such as Regorafenib show high sensitivity and tumor specificity to ATCC cell lines (ATCC vs Normal liver P=0.00017***), but this specificity was reduced and lost in patient-derived 2D cultures (P=0.045*) and organoids (P=0.895), respectively. This may explain the observed hepatotoxicity observed in HCC patients and warrant further investigation of more targeted ways of treating HCC.

Citation Format: Alissa Michelle Go Wong, Winnie Cheung, Maggie Wong, Aikha Wong, Helena Lam, Zhe Zhang, Matthew Man, Hui Chen, David Close, Paul Johnston, Anthony Chan, Paul Lai, Joseph Kwong, Nathalie Wong. High-throughput screening of patient-derived HCC organoids for drug discovery [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3911.

Novel HDAC5-interacting motifs of Tbx3 are essential for the suppression of E-cadherin expression and for the promotion of metastasis in hepatocellular carcinoma

Tbx3, a transcriptional repressor, is essential in the organogenesis of vertebrates, stem cell self-renewal and differentiation, and the carcinogenesis of multiple tumor types. However, the mechanism by which Tbx3 participates in the metastasis of hepatocellular carcinoma (HCC) remains largely unknown. In this study, we show that Tbx3 was dramatically upregulated in clinical HCC samples and that elevated expression of Tbx3 promoted cancer progression. To determine the underlying mechanism, systematic glycine scan mutagenesis and deletion assays were performed. We identified two critical motifs, ⁵⁸⁵LFSYPYT⁵⁹¹ and ⁶⁰⁴HRH⁶⁰⁶, that contribute to the repression of transcriptional activity. These motifs are also essential for Tbx3 to promote cell migration and metastasis both in vitro and in vivo via the suppression of E-cadherin expression. More importantly, Tbx3 directly interacts with HDAC5 via these motifs, and an HDAC inhibitor blocks Tbx3-mediated cell migration and the downregulation of E-cadherin in HCC. As Tbx3 is involved in the carcinogenesis of multiple types of human cancers, our findings suggest an important target for anti-cancer drug development.

A regulatory protein that represses gene activity interacts with an enzyme involved in chromosome remodeling to promote the migration and metastasis of liver cancer cells. Ming-Liang He from the City University of Hong Kong and colleagues found that levels of the T-box transcription factor Tbx3 were dramatically increased in tissue biopsies of liver tumors. They injected Tbx3-expressing human liver cancer cells into mice and saw a positive correlation between Tbx3 activity and cancer progression. By mutating and deleting parts of Tbx3, the researchers identified two particular stretches of the protein that bind histone deacetylase 5, an enzyme involved in ensuring DNA coils, are wound tight to suppress gene activity. This interaction is needed for Tbx3’s tumor-promoting function and may be targetable with drugs in order to prevent metastasis in patients with aggressive liver cancer.

A nomogram integrating hepatic reserve and tumor characteristics for hepatocellular carcinoma following curative liver resection

BACKGROUND

Because of the mutual influence of liver dysfunction and malignancy, overall survival (OS) is a composite clinical endpoint in hepatocellular carcinoma (HCC). We developed a nomogram integrating albumin-bilirubin (ALBI) grade, a new index of hepatic reserve, and tumor characteristics of HCC for predicting OS following curative liver resection.

METHODS

The nomogram was built to estimate the probabilities of 1, 3, and 5-y OS based on training cohort of 709 HCC, which was validated in an international independent dataset. The prognostic value of the nomogram was determined by concordance index (C-index), time-dependent receiver operating characteristics (tdROC), and decision curves, comparing with ALBI grade alone, the Cancer of the Liver Italian Program (CLIP), the Barcelona Clinic Liver Cancer (BCLC), and Okuda staging systems.

RESULTS

Independent factors derived from multivariable Cox analysis of the training cohort to predict OS were tumor grade, microvascular invasion, tumor size and ALBI grade which were assembled into nomogram. The calibration curves for probability of OS showed optimal agreement between nomogram-prediction and actual observation, which was tested in validation cohort. The C-index, tdROC and decision curves showed the nomogram was superior to CLIP, ALBI grade, BCLC and Okuda. The patients could also be stratified into low, intermediate risk, and high risk of the mortality by the normogram in both development and validation cohorts.

CONCLUSIONS

The nomogram integrating hepatic reserve and tumor characteristics provided a highly accurate estimation of OS in patients with HCC after curative liver resection, contributing to assess patient prognosis.

Toll-like receptor 2 costimulation potentiates the antitumor efficacy of CAR T Cells

Chimeric antigen receptor (CAR) T-cell immunotherapies have shown unprecedented success in treating leukemia but limited clinical efficacy in solid tumors. Here, we generated 1928zT2 and m28zT2, targeting CD19 and mesothelin, respectively, by introducing the Toll/interleukin-1 receptor domain of Toll-like receptor 2 (TLR2) to 1928z and m28z. T cells expressing 1928zT2 or m28zT2 showed improved expansion, persistency and effector function against CD19⁺ leukemia or mesothelin⁺ solid tumors respectively in vitro and in vivo. In a patient with relapsed B-cell acute lymphoblastic leukemia, a single dose of 5 × 10⁴/kg 1928zT2 T cells resulted in robust expansion and leukemia eradication and led to complete remission. Hence, our results demonstrate that TLR2 signaling can contribute to the efficacy of CAR T cells. Further clinical trials are warranted to establish the safety and efficacy of this approach.

Overflow models for the admission of intensive care patients

An earlier article, inspired by overflow models in telecommunication systems with multiple streams of telephone calls, proposed a new analytical model for a network of intensive care units (ICUs), and a new patient referral policy for such networks to reduce the blocking probability of external emergency patients without degrading the quality of service (QoS) of canceled elective operations, due to the more efficient use of ICU capacity overall. In this work, we use additional concepts and insights from traditional teletraffic theory, including resource sharing, trunk reservation, and mutual overflow, to design a new patient referral policy to further improve ICU network efficiency. Numerical results based on the analytical model demonstrate that our proposed policy can achieve a higher acceptance level than the original policy with a smaller number of beds, resulting in improved service for all patients. In particular, our proposed policy can always achieve much lower blocking probabilities for external emergency patients while still providing sufficient service for internal emergency and elective patients. In addition, we provide new accurate and computationally efficient analytical approximations for QoS evaluation of ICU networks using our proposed policy. We demonstrate numerically that our new approximation method yields more accurate, robust and conservative results overall than the traditional approximation. Finally, we demonstrate how our proposed approximation method can be applied to solve resource planning and optimization problems for ICU networks in a scalable and computationally efficient manner.

Impact of disease stage and aetiology on survival in hepatocellular carcinoma: implications for surveillance

BACKGROUND

Variation in survival in hepatocellular carcinoma (HCC) has been attributed to different aetiologies or disease stages at presentation. While international guidelines recommend surveillance of high-risk groups to permit early diagnosis and curative treatment, the evidence that surveillance decreases disease-specific mortality is weak.

METHODS

We compared HCC survival figures from Japan (n=1174) and Hong Kong (n=1675) over similar time periods (Japan 2000-2013, Hong Kong, China 2003-2014). The former has an intensive national surveillance programme, while the latter has none. We also analysed changes in survival in Japan over a 50-year period including data from before and after institution of a national HCC surveillance programme.

RESULTS

In Japan, over 75% of cases are currently detected by surveillance, whereas in Hong Kong <20% of cases are detected presymptomatically. Median survival was 52 months in Japan and 17.8 months in Hong Kong; this survival advantage persisted after allowance for lead-time bias. Sixty-two per cent of Japanese patients had early disease at diagnosis and 63% received curative treatment. The comparable figures for Hong Kong were 31.7% and 44.1%, respectively. These differences could not be accounted for by disease aetiology, and patients in Hong Kong who were detected at an early stage had a similar survival to the analogous patients in Japan.

CONCLUSIONS

The variation in survival is largely accounted for by stage at diagnosis, which in turn relates to the intensity of surveillance programmes and the consequent variation in curative therapeutic options.

Transarterial chemo-embolisation of hepatocellular carcinoma: impact of liver function and vascular invasion

Background:

Transarterial chemo-embolisation (TACE) is recommended for patients with BCLC intermediate stage hepatocellular carcinoma (stage B), particularly in patients with good underlying liver function and minimal symptoms. The hepatoma arterial embolisation prognostic (HAP) score combines measures of liver function and tumour-related factors to offer a simple prognostic scoring system. The Albumin-Bilirubin (ALBI) grade permits assessment of the impact of liver function on survival. We aimed to investigate these two models and vascular invasion (VI).

Methods:

In an international cohort of 3030 patients undergoing TACE, we examined the impact of liver function as assessed by the ALBI score, the HAP score and VI on survival.

Results:

Classification according to ALBI grade resulted in non-overlapping survival curves in the overall data set and all regional cohorts. The HAP score was also validated. Tumour number, aetiology and VI were identified as additional independent prognostic risk factors not currently included in the HAP score. Survival was particularly poor for patients with VI.

Conclusions:

The ALBI grade categorised patients receiving TACE into three clear prognostic groups, thereby emphasising the importance of underlying liver function in the outcome of TACE. The HAP score has been validated internationally and the serious adverse impact of VI is clearly shown.

Modeling Current Density Maps Using Aliev-Panfilov Electrophysiological Heart Model

Most existing studies of cardiac arrhythmia rely on surface measurements through optical or electrical mapping techniques. Current density imaging (CDI) is a method which enables us to study current pathways inside the tissue. However, this method entails implementation complexities for beating ex vivo hearts. Hence, this work presents an approach to simulate and study the current distributions in different cardiac electrophysiological states. The results are corroborated by experimental data, and they indicate that different states were distinguishable. The CDI simulations can be used for studying cardiac arrhythmias under simulation conditions which are otherwise impossible or difficult to be implemented experimentally.

Palliative chemotherapy in advanced colorectal cancer patients 80 years of age and older

BACKGROUND

Colorectal cancer (crc) has a median diagnostic age of 68 years. Despite significant progress in chemotherapy (ctx) options, few data on outcomes or toxicity from ctx in patients 80 years of age and older are available. We investigated ctx in such patients with metastatic crc (mcrc), hypothesizing high rates of hospitalization and toxicity.

METHODS

A retrospective chart review identified patients 80 years of age and older with mcrc who initiated ctx between 2005-2010 at our institution. Patient demographics and ctx data were collected. Endpoints included rates of hospitalization, ctx discontinuation because of toxicity, and overall survival.

RESULTS

In 60 patients, ctx was initiated on 88 occasions. Median age in the cohort was 83 years; 52% were men; 72% lived with family; 53% had a modified Charlson comorbidity index of 2 or greater; and 31% were taking 6 or more prescription medications at baseline. At baseline, 33% of the patients were anemic (hemoglobin < 100 g/L), 36% had leukocytosis (white blood cells > 11×10(9)/L), and 48% had renal impairment (estimated glomerular filtration rate < 60 mL/min/1.73 m(2)). In 53%, ctx was given as first-line treatment. The initial ctx dose was adjusted in 67%, and capecitabine was the most common chemotherapeutic agent (45%). In 19 instances (22%), the patient was hospitalized during or within 30 days of ctx; in 26 instances (30%), the ctx was discontinued because of toxicity, and in 48 instances (55%), the patient required at least 1 dose reduction, omission, or delay. Median overall survival was 17.8 months (95% confidence interval: 14.3 to 20.8 months).

CONCLUSIONS

In the population 80 years of age and older, ctx for mcrc is feasible; however, most recipients will require dose adjustments, and a significant proportion will be hospitalized or stop ctx because of toxicity. Prospective research incorporating geriatric assessment tools is required to better select these older patients for ctx.

Fusion of structural and functional cardiac magnetic resonance imaging data for studying ventricular fibrillation

Magnetic Resonance Imaging (MRI) techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) provide a complementing set of imaging data that can describe both the functional and structural states of biological tissues. This paper presents a Joint Independent Component Analysis (jICA) based fusion approach which can be utilized to fuse CDI and DTI data to quantify the differences between two cardiac states: Ventricular Fibrillation (VF) and Asystolic/Normal (AS/NM). Such an approach could lead to a better insight on the mechanism of VF. Fusing CDI and DTI data from 8 data sets from 6 beating porcine hearts, in effect, detects the differences between two cardiac states, qualitatively and quantitatively. This initial study demonstrates the applicability of MRI-based imaging techniques and jICA-based fusion approach in studying cardiac arrhythmias.

A novel approach to quantification of real and artifactual components of current density imaging for phantom and live heart

Spatial distribution of injected current in a subject could be calculated and visualized through current density imaging (CDI). Calculated CDI paths however have a limited degree of accuracy due to both avoidable methodological errors and inevitable limitations dictated by MR imaging constraints. The source and impact of these limitations are scrutinized in this paper. Quantification of such limitations is an essential step prior to passing any judgment about the results especially in biomedical applications. An innovative technique along with metrics for evaluation of range of errors using baseline and phase cycle MR images is proposed in this work. The presented approach is helpful in pinpointing the local artifacts (areas for which CDI results are suspect), evaluation of global noises and artifacts and assessment of the effect of approximation algorithms on real and artifactual components. We will demonstrate how this error/reliability evaluation is applicable to interpretation of CDI results and in this framework, report the CDI results for an artificial phantom and a live pig heart in Langendorff setup. It is contended here that using this method, the inevitable trade-off between details and approximations of CDI components could be monitored which provides a great opportunity for robust interpretation of results. The proposed approach could be extended, adapted and used for statistical analysis of similar methods which aim at mapping current and impedance based on magnetic flux images obtained through MRI.

Assessment of liver function in patients with hepatocellular carcinoma: a new evidence-based approach-the ALBI grade

PURPOSE

Most patients with hepatocellular carcinoma (HCC) have associated chronic liver disease, the severity of which is currently assessed by the Child-Pugh (C-P) grade. In this international collaboration, we identify objective measures of liver function/dysfunction that independently influence survival in patients with HCC and then combine these into a model that could be compared with the conventional C-P grade.

PATIENTS AND METHODS

We developed a simple model to assess liver function, based on 1,313 patients with HCC of all stages from Japan, that involved only serum bilirubin and albumin levels. We then tested the model using similar cohorts from other geographical regions (n = 5,097) and other clinical situations (patients undergoing resection [n = 525] or sorafenib treatment for advanced HCC [n = 1,132]). The specificity of the model for liver (dys)function was tested in patients with chronic liver disease but without HCC (n = 501).

RESULTS

The model, the Albumin-Bilirubin (ALBI) grade, performed at least as well as the C-P grade in all geographic regions. The majority of patients with HCC had C-P grade A disease at presentation, and within this C-P grade, ALBI revealed two classes with clearly different prognoses. Its utility in patients with chronic liver disease alone supported the contention that the ALBI grade was indeed an index of liver (dys)function.

CONCLUSION

The ALBI grade offers a simple, evidence-based, objective, and discriminatory method of assessing liver function in HCC that has been extensively tested in an international setting. This new model eliminates the need for subjective variables such as ascites and encephalopathy, a requirement in the conventional C-P grade.

Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images

Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 [Formula: see text] formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

Manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts

Aims:

To report the technique and outcomes of sutureless manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts.

Materials and Methods:

This retrospective study comprised of 112 eyes of 83 patients with mature cataract who all had manual cataract extraction via a subconjunctival limbus oblique incision. A transconjunctival tunnel is fashioned with a 3.0 mm keratome, 0.5 mm behind the limbal vascular arcades. A limbal tunnel, with a transverse extent of 9 mm in the cornea and 7.0 mm in the limbus, is created beneath the conjunctival/Tenon's tissue using an angled bevel-up crescent blade. Outcome measures included visual acuity, intraoperative complications, surgically induced astigmatism, endothelial cell loss rate and surgery time.

Results:

Self-sealing wound was achieved in 112 eyes (98.2%). The nucleus was delivered in whole in 108 eyes (96.4%). Intraoperative complications included hyphema in 3 eyes (2.7%), iridodialysis in 2 eyes 1.8%), posterior capsular rupture and zonular dialysis in 2 eyes (1.8%). At the 3-month follow-up, 91% patients achieved a best-corrected visual acuity of 20/20 or better, the mean of surgically induced astigmatism was -0.62 ± 0.41 Diopters and endothelial cell loss was 4.2%. Average surgical time was 3.75 min per case.

Conclusion:

This subconjunctival limbus oblique incision has the potential to serve as safe and effective technique for mature cataracts.

Unresectable hepatocellular carcinoma: randomized controlled trial of transarterial ethanol ablation versus transcatheter arterial chemoembolization

PURPOSE

To compare effectiveness of transarterial ethanol ablation (TEA) and transcatheter arterial chemoembolization (TACE) for unresectable hepatocellular carcinoma and determine whether TEA leads to better overall survival and tumor response than TACE.

MATERIALS AND METHODS

In this institutional review board-approved preregistered randomized controlled trial (n = 200), informed consent was obtained. Primary outcome was overall survival; secondary outcomes were time to progression (TTP), progression-free survival (PFS), tumor response at computed tomography, and treatment-related toxicity. Eligible patients were randomized at a 1:1 ratio. Treatment included transcatheter delivery of ethiodized oil-ethanol mixture (2:1 ratio by volume up to 60 mL) for TEA and cisplatin-ethiodized oil emulsion (0.5 mg cisplatin per milliliter up to 30 mg), followed by 1-mm gelatin-sponge pellets, for TACE. Study was terminated after interim analysis (n = 98); 90 patients were available for analysis. Overall survival, TTP, and PFS were analyzed with Kaplan-Meier method; differences were compared with log-rank test.

RESULTS

Study was terminated prematurely after interim analysis, which showed no difference in overall survival; this was unlikely to change with further patient accrual. Median overall survival in TEA and TACE was 24.3 months (95% confidence interval [CI]: 12.8, 32.7) and 20.1 months (95% CI: 9.3, 31.2), respectively (P = .358). Median TTP and PFS for intralesional progression were longer with TEA than TACE (TTP, 34.6 months [95% CI: 28.2, 41] vs 26.05 months [95% CI: 18.7, 33.3]; PFS, 14.8 months [95% CI: 10.2, 19.5] vs 9.3 months [95% CI: 7.1, 11.5]) (P = .028 and 0.029, respectively). Complete response rate on a tumor basis was persistently and significantly higher with TEA at 3 months (62 of 88 [70%] vs 39 of 76 [51%], P = .012), 6 months (64 of 88 [73%] vs 41 of 76 [54%], P = .012), and 12 months (66 of 88 [75%] vs 45 of 76 [59%], P = .031).

CONCLUSION

Although there was no significant difference in overall survival, TEA demonstrated better complete tumor response, longer time to intralesional progression, and longer PFS.

mTORC1/2 targeted by n-3 polyunsaturated fatty acids in the prevention of mammary tumorigenesis and tumor progression

Although epidemiological and preclinical studies have shown the preventative effects of n-3 polyunsaturated fatty acids (PUFAs) on breast cancer, inconsistencies still remain in the data and the underlying mechanisms remain unclear. In this study, we identified mammalian target of rapamycin (mTOR) signaling, which plays an essential role in cell proliferation and breast tumorigenesis, as a target of n-3 PUFAs. In breast cancer cell lines, n-3 PUFAs rapidly and efficiently suppress both mTOR complex 1 (mTORC1) and mTORC2 and their downstream signaling, and subsequently inhibit cell proliferation and angiogenesis while promoting apoptosis. Further study indicates that stabilization of the mTOR-raptor complex by n-3 PUFAs may contribute to their inhibitory effect on mTORC1. Importantly, four complementary and well-controlled animal models were utilized to identify the role and molecular target of n-3 PUFAs in the prevention of breast carcinogenesis and progression, namely: (1) chemically induced mammary tumor rats with a high dietary intake of n-3 PUFAs; (2) nude mice implanted with mammary tumor cell lines stably expressing fat-1, a desaturase that catalyzes the conversion of n-6 to n-3 PUFAs and produces n-3 PUFAs endogenously; (3) fat-1 transgenic severe combined immune deficiency mice implanted with breast tumor cells; and (4) the fat-1 transgenic mouse mammary tumor virus-polyoma virus middle T oncogene double-hybrid mice, a model of aggressive breast cancer. In summary, dietary and endogenous n-3 PUFAs abrogate the activity of mTORC1/2 pathways in vitro and in vivo and prevent breast carcinogenesis, tumor growth and metastasis. Taken together, our findings convincingly clarify the causal relationship between n-3 PUFAs and breast cancer prevention and establish mTORC1/2 as a target of n-3 PUFAs.

Using Video Acquired from an Unmanned Aerial Vehicle (UAV) to Measure Fracture Orientation in an Open-Pit Mine

This project explored the feasibility of using video images acquired with an unmanned aerial vehicle (UAV) to obtain three-dimensional (3D) point clouds using structure from motion (SfM) software. Missions were flown using an Aeryon Scout: a lightweight, vertical take-off and landing quadrotor micro UAV with a miniature video camera. The initial mission captured urban scene images that were used to assess system performance while the main mission focused on rock walls where 3D images were used to successfully measure fracture orientations. Point clouds generated from this combination of technologies were sparse, but in the future, improvements in the resolution of original video images would cascade through the processing and improve the overall results. Such a system could have a multitude of applications in the mining industry, contributing to both safety and financial considerations.

Polymorphism of the melatonin receptor genes and its relationship with seasonal reproduction in the Gulin Ma goat breed

Melatonin is thought to be the main molecule that transmits the signal of seasonal change to the neuroendocrine system in seasonal breeding species. Melatonin exerts its effects through specific melatonin receptors, MTNR1A and MTNR1B. In the present study, six native goat breeds in China and one introduced goat breed were analysed to investigate the relationship between the genetic polymorphism of receptor genes and seasonal reproduction. Sequencing results showed that there were five polymorphic mutations in the MTNR1A gene and two in the MTNR1B gene. In the MTNR1A gene, genotypes AA, AB and BB for 424C>T and genotypes CC, CD and DD for 589C>A were observed in these goat breeds. In all six native goat breeds, only genotype AA was detected. In the MTNR1B gene, genotypes EE, EF and FF for 1179G>A and genotypes GG, GH and HH for 1529A>G were detected. However, in Gulin Ma goats, the genotypes EE and HH were not found. Moreover, the base of G at position 1179 and A at position 1529 were linked (By Arlequin ver 3.1, Zoological Institute, Berne, Switzerland, http://cmpg.unibe.ch/software/arlequin3,D' = 0.7496, r(2)  = 0.4421, χ(2)  = 489.8679, p = 0.000). Among these mutations, no amino acid change was found in MTNR1A, while both of the mutations in MTNR1B gene caused amino acid changes of R222H and S339G, respectively. The structural analysis showed that the R222H mutation occurred in the first amino acid residue of the third cytoplasmic loop, and the S339G mutation was located in the carboxyl terminus of the protein. In terms of seasonal breeding, all the genotypes we detected showed a similar kidding frequency distribution trend with a higher frequency in May-August than in January-April and in September-December. This suggests that the relationship between the polymorphisms in the MTNR1A and MTNR1B genes and seasonal breeding could not be established.

Analysis of reliability metrics and quality enhancement measures in current density imaging

Low frequency current density imaging (LFCDI) is a magnetic resonance imaging (MRI) technique which enables calculation of current pathways within the medium of study. The induced current produces a magnetic flux which presents itself in phase images obtained through MRI scanning. A class of LFCDI challenges arises from the subject rotation requirement, which calls for reliability analysis metrics and specific image registration techniques. In this study these challenges are formulated and in light of proposed discussions, the reliability analysis of calculation of current pathways in a designed phantom and a pig heart is presented. The current passed is measured with less than 5% error for phantom, using CDI method. It is shown that Gauss's law for magnetism can be treated as reliability metric in matching the images in two orientations. For the phantom and pig heart the usefulness of image registration for mitigation of rotation errors is demonstrated. The reliability metric provides a good representation of the degree of correspondence between images in two orientations for phantom and pig heart. In our CDI experiments this metric produced values of 95% and 26%, for phantom, and 88% and 75% for pig heart, for mismatch rotations of 0 and 20 degrees respectively.

Cisplatin induces serotonin release from human peripheral blood mononuclear cells of cancer patients and methylprednisolone inhibits this effect

The aim of this study was to verify whether cisplatin (CDDP) can induce serotonin (5HT) release from peripheral blood mononuclear cells (PBMC) of cancer patients and determine whether methylprednisolone (MP) can inhibit such release. Ten patients (mean age 61.8 years) with cancer of different sites, all but one in advanced stage of disease were studied. Our study showed that unstimulated PBMC of cancer patients release a higher amount of 5HT than that of healthy subjects (57+/-5 nM vs 10+/-1 nM, p<0.001) and that similarly the stimulation with PHA or CDDP induces a higher amount of 5HT release by PBMC of cancer patients than that by PBMC of healthy subjects (74+/-6 vs 32+/-3 nM, p<0.001 and 91+/-8 vs 18+/-2 nM, p<0.001, respectively). The addition of MP to the culture in the presence of CDDP induced a significant decrease of 5HT levels: from 91+/-8 to 53+/-7 nM, p=0.002. This result obtained in cancer patients paralleled that previously obtained by us in healthy subjects. Our data confirm a new mechanism through which CDDP could induce emesis and provide a further possible explanation to the anti-emetic activity of corticosteroids, such as MP.

Mutations of p53 gene in hepatocellular-carcinoma (hcc) correlate with tumor progression and patient prognosis - a study of 138 patients with unifocal hcc

The mutation spectrum of p53 gene and its biological significance were studied in 138 patients with unifocal primary hepatocellular carcinoma (HCC) in Taiwan. The p53 mutations were detected in 51 cases (37%); 36 (71%) were missense mutations. The others (29%) included mutations at the intron-exon junctions (5 cases), deletion or insertion (4 cases), nonsense mutations (4 cases), and silent mutations (2 cases). The mutation sites were scattered from exons 4 to 10, predominantly (75%) in exons 5, 7, and 8. Of these mutations, 72% were transversions, mostly G:C --> T:A change (46%); while only 28% were transitions. Mutation occurred at codon 249 only in 14 cases (10%), but accounted for 27% of the mutations. The p53 mutations correlated with allele loss of p53 locus (52% vs 17% p<0.02), alpha-fetoprotein elevation (45% vs 28%, p<0.04), and poorly differentiated HCC (46% vs 10%, p<0.0001). The p53 mutation rate was two times higher in large than in small HCC (48% vs 26%, p<0.008), and in more advanced tumor (stage 3 vs stages 1 and 2: 49% vs 21%, p<0.0007). HCC patients with mutated p53 gene had a worse outcome (5-year survival; 18% vs 38%, p<0.008). We conclude that p53 gene mutation is common in advanced HCC, occurs as a late event in HCC growth, correlates with tumor progression and aggression, and is a useful molecular prognostic parameter of HCC. The p53 mutation patterns did not correlate with HBV or HCV infection. The frequency of p53 mutations did not differ between Taiwanese patients and mainland Chinese in Taiwan. However, mutation at codon 249 was more common in Taiwanese patients (p<0.05), while mutations of other types more frequent in the mainlanders (p<0.03). Hence endogenous and exogenous factors other than aflatoxin may also play a role in p53 mutation in HCC.

Primate-specific microRNA-637 inhibits tumorigenesis in hepatocellular carcinoma by disrupting signal transducer and activator of transcription 3 signaling

MiR-637 (microRNA-637) is a primate-specific miRNA belonging to the small noncoding RNA family, which represses gene regulation at the post-transcriptional expression level. Although it was discovered approximately 5 years ago, its biomedical significance and regulatory mechanism remain obscure. Our preliminary data showed that miR-637 was significantly suppressed in four HCC cell lines and, also, in most of the hepatocellular carcinoma (HCC) specimens, thereby suggesting that miR-637 would be a tumor suppressor in HCC. Simultaneously, the enforced overexpression of miR-637 dramatically inhibited cell growth and induced the apoptosis of HCC cells. The transcription factor, signal transducer and activator of transcription 3 (Stat3), is constitutively activated in multiple tumors, and aberrant Stat3 activation is linked to the promotion of growth and desensitization of apoptosis. Our study showed that Stat3 tyrosine 705 phosphorylation and several Stat3-regulated antiapoptotic genes were down-regulated in miR-637 mimics-transfected and Lv-miR637-infected HCC cells. In addition, miR-637 overexpression negatively regulated Stat3 phosphorylation by suppressing autocrine leukemia inhibitory factor (LIF) expression and exogenous LIF-triggered Stat3 activation and rescued cell growth in these cells. A nude mice model also demonstrated the above-described results, which were obtained from the cell model. Furthermore, we found that LIF was highly expressed in a large proportion of HCC specimens, and its expression was inversely associated with miR-637 expression.

CONCLUSION

Our data indicate that miR-637 acted as a tumor suppressor in HCC, and the suppressive effect was mediated, at least in part, by the disruption of Stat3 activation.

PRACTICAL PARALLEL IMAGING COMPRESSED SENSING MRI: SUMMARY OF TWO YEARS OF EXPERIENCE IN ACCELERATING BODY MRI OF PEDIATRIC PATIENTS

For the last two years, we have been experimenting with applying compressed sensing parallel imaging for body imaging of pediatric patients. It is a joint-effort by teams from UC Berkeley, Stanford University and GE Healthcare. This paper aims to summarize our experience so far. We describe our acquisition approach: 3D spoiled-gradient-echo with poisson-disc random undersampling of the phase encodes. Our re-construction approach: ℓ₁-SPIRiT, an iterative autocalibrating parallel imaging reconstruction that enforces both data consistency and joint-sparsity in the wavelet domain. Our implementation: an on-line parallelized implementation of ℓ₁-SPIRiT on multi-core CPU and General Purpose Graphics Processors (GPGPU) that achieves sub-minute 3D reconstructions with 8-channels. Clinical results showing higher quality reconstruction and better diagnostic confidence than parallel imaging alone at accelerations on the order of number of coils.

A systematic review of interventions by healthcare professionals on community-dwelling postmenopausal women with osteoporosis

A systematic review was conducted to evaluate evidence concerning the effect of non-drug interventions by healthcare professionals on community-dwelling postmenopausal osteoporotic women. Evidence available indicates that such interventions are effective in improving the quality of life, medication compliance, and calcium intake, but effect on other outcomes is less conclusive.

INTRODUCTION

The purpose of this study is to conduct a systematic review to evaluate evidence concerning the effect of non-drug interventions by healthcare professionals on community-dwelling postmenopausal osteoporotic women.

METHODS

Randomized controlled trials (RCTs) published in English between year 1990 and 2009 were identified. Types of patient outcome used as assessment included quality of life (QOL), bone mineral density (BMD), medication compliance and persistence, knowledge level, and lifestyle modification.

RESULTS

Twenty four RCTs met the inclusion criteria. Seven studies assessed interventions by physiotherapists, six by physicians, seven by nurses, three by multi-disciplinary teams and one by dietitians. Variability in the types and intensity of interventions made comparison between each study difficult. Collectively, these studies provided some evidence to show that interventions by healthcare professionals improved the QOL medication compliance and calcium intake of patients but its effects on BMD, medication persistence, knowledge, and other lifestyle modifications were less conclusive.

CONCLUSIONS

From this review, it was found that some outcome measures of such non-drug interventions still required further studies. Future studies should use validated instruments to assess the outcomes, with focus on common definitions of interventions and outcome measures, more intensive one-to-one interventions, appropriate control groups, adequate randomization procedures, and also provide information on effect size.

Utility of virosomal adjuvated influenza vaccines: a review of the literature

In spite of the efforts of the World Health Organization (WHO), influenza continues to be a major public health problem, both because of its impact on the health of subjects at risk, such as the elderly, and because of the economic burden that it places on society. Adjuvants are agents which, when incorporated into vaccines, enhance the immunogenicity of their antigens. The need for ever more immunogenic and efficacious influenza vaccines has led to the development of innovative vaccines. One of these, the virosomal vaccine, has been on the market since 1997. The results obtained through controlled clinical studies and widespread application in the field suggest that the virosomal vaccine is not only an important tool for the prevention of seasonal influenza but also a valid means of potentiating the effect of a pandemic influenza vaccine and, perhaps, of preparing multivalent or combined vaccines.