Thermal and chemical inactivation of Lactobacillus virulent bacteriophage

The effect of thermal treatments and several biocides on the viability of Lactobacillus virulent phage P1 was evaluated. Times to achieve 99% inactivation (T₉₉) of phage at different treatment conditions were calculated. The thermal treatments applied were 63, 72, and 90°C in 3 suspension media (de Man, Rogosa, Sharpe broth, reconstituted skim milk, and Tris magnesium gelatin buffer). Phage P1 was completely inactivated in 5 and 10 min at 90 and 72°C, respectively; however, reconstituted skim milk provided better thermal protection at 63°C. When phage P1 was treated with various biocides, 800 mg/L of sodium hypochlorite was required for total inactivation (∼7.3 log reduction) within 60 min, whereas treatment with 100% ethanol resulted in only a ∼4.7 log reduction, and 100% isopropanol resulted in a 5.2-log reduction. Peracetic acid (peroxyacetic acid) at the highest concentration used (0.45%) resulted in only a ∼4.-log reduction of phage within 60 min. The results of this study provide additional information on effective treatments for the eradication of potential phage infections in dairy plants.

Abstract P6-12-06: Nonsteroidal, tissue selective androgen receptor modulator (SARM), enobosarm, reduces growth of androgen receptor-positive breast cancer in patient-derived preclinical models

Introduction: In breast cancer the androgen receptor (AR) is the most abundantly expressed steroid receptor with 75-95% of estrogen receptor (ER)-positive and 40-70% of ER-negative breast cancers expressing the AR. Historically, advanced breast cancer has been treated with androgens, resulting in significant clinical response. However, the use of steroidal androgens fell from favor as a result of their virilizing side effects. Nonsteroidal, tissue selective androgen receptor modulators (SARMs) will provide a novel targeted approach to exploit the therapeutic benefits of androgens in breast cancer.

Aims: To test the effects of enobosarm (a first-in-class SARM) and enzalutamide (AR antagonist) on the growth of patient-derived breast cancer xenografts (PDX) and to discern the mechanism of action of AR-targeted therapies in AR-positive breast cancer.

Materials and Methods: AR-positive PDXs with varying receptor expression (ER, progesterone receptor (PR), and HER2) were implanted in immunecompromised mice. Mice carrying PDXs were treated with vehicle, 10 mg/kg/day (mpk) enobosarm (GTx, Inc., Memphis, TN), or 20 mpk enzalutamide (Medivation Inc.), orally. Tumor volume was measured twice or thrice weekly. Tumors that received enobosarm were further analyzed to determine the mechanism of action.

Results: Enobosarm significantly (p<0.01) inhibited the growth of ER-, PR-, and HER2- positive HCI-7 and ER- and PR- negative and HER2-positive HCI-12 PDX. While enobosarm inhibited the growth of HCI-12 by ~80% and HCI-7 by ~60%, enzalutamide failed to inhibit the growth of the HCI-7 PDX. In contrast, neither enobosarm nor enzalutamide inhibited the growth of ER- and PR-negative and HER2-positive HCI-9 PDX, consistent with the heterogeneity of AR-positive breast cancers. Growth of two triple-negative breast cancer (TNBC) PDXs were inhibited by 30-40% by enobosarm, but not by enzalutamide. These results were reproduced in xenografts developed with breast cancer cell lines, MCF-7 and MDA-MB-231 expressing the AR. Gene expression studies conducted with the HCI-12 tumors indicated that enobosarm inhibited the expression of various proliferative genes (MUC2, IL10RA, IGSF1, SLC6A4, and others) and increased the expression of growth inhibitory genes (CYP4F8, MYBPC1, and others). Ingenuity pathway analysis demonstrated that enobosarm inhibited genes that are downstream of HER2 signaling. Interestingly, miR-21-3p, which has been implicated in chemo-resistance, was consistently expressed at approximately 10-50-fold higher than miR-21-5p in PDXs. This imbalance was partially reversed by enobosarm.

Conclusion: These results indicate that AR-positive breast cancers are highly heterogeneous and that enobosarm has promise as novel targeted therapy to treat AR-positive breast cancer. Enobosarm is currently in phase II clinical trial in both ER-positive breast cancer and in TNBC patients.

Citation Format: Narayanan R, Ponnusamy S, Fan M, Yang CH, Grimes BL, Fleming MD, Pritchard EF, Berry MP, Oswaks RM, Fine RE, Loiseau J-C, Schwartzberg LS, Pfeffer LM. Nonsteroidal, tissue selective androgen receptor modulator (SARM), enobosarm, reduces growth of androgen receptor-positive breast cancer in patient-derived preclinical models [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 P6-12-06.

Cortical Thickness of Native Tibetans in the Qinghai-Tibetan Plateau

BACKGROUND AND PURPOSE

High-altitude environmental factors and genetic variants together could have exerted their effects on the human brain. The present study was designed to investigate the cerebral morphology in high-altitude native Tibetans.

MATERIALS AND METHODS

T1-weighted brain images were obtained from 77 Tibetan adolescents on the Qinghai-Tibetan Plateau (altitude, 2300-5300 m) and 80 matched Han controls living at sea level. Cortical thickness, curvature, and sulcus were analyzed by using FreeSurfer.

RESULTS

Cortical thickness was significantly decreased in the left posterior cingulate cortex, lingual gyrus, superior parietal cortex, precuneus, and rostral middle frontal cortex and the right medial orbitofrontal cortex, lateral occipital cortex, precuneus, and paracentral lobule. Curvature was significantly decreased in the left superior parietal cortex and right superior marginal gyrus; the depth of the sulcus was significantly increased in the left inferior temporal gyrus and significantly decreased in the right superior marginal gyrus, superior temporal gyrus, and insular cortex. Moreover, cortical thickness was negatively correlated with altitude in the left superior and middle temporal gyri, rostral middle frontal cortex, insular cortex, posterior cingulate cortex, precuneus, lingual gyrus, and the right superior temporal gyrus. Curvature was positively correlated with altitude in the left rostral middle frontal cortex, insular cortex, and middle temporal gyrus. The depth of the sulcus was negatively correlated with altitude in the left lingual gyrus and right medial orbitofrontal cortex.

CONCLUSIONS

Differences in cortical morphometry in native Tibetans may reflect adaptations related to high altitude.

White matter predicts functional connectivity in premanifest Huntington's disease

Objectives

The distribution of pathology in neurodegenerative disease can be predicted by the organizational characteristics of white matter in healthy brains. However, we have very little evidence for the impact these pathological changes have on brain function. Understanding any such link between structure and function is critical for understanding how underlying brain pathology influences the progressive behavioral changes associated with neurodegeneration. Here, we demonstrate such a link between structure and function in individuals with premanifest Huntington's.

Methods

Using diffusion tractography and resting state functional magnetic resonance imaging to characterize white matter organization and functional connectivity, we investigate whether characteristic patterns of white matter organization in the healthy human brain shape the changes in functional coupling between brain regions in premanifest Huntington's disease.

Results

We find changes in functional connectivity in premanifest Huntington's disease that link directly to underlying patterns of white matter organization in healthy brains. Specifically, brain areas with strong structural connectivity show decreases in functional connectivity in premanifest Huntington's disease relative to controls, while regions with weak structural connectivity show increases in functional connectivity. Furthermore, we identify a pattern of dissociation in the strongest functional connections between anterior and posterior brain regions such that anterior functional connectivity increases in strength in premanifest Huntington's disease, while posterior functional connectivity decreases.

Interpretation

Our findings demonstrate that organizational principles of white matter underlie changes in functional connectivity in premanifest Huntington's disease. Furthermore, we demonstrate functional antero–posterior dissociation that is in keeping with the caudo–rostral gradient of striatal pathology in HD.

A decision support tool for evaluating the air quality and wind comfort induced by different opening configurations for buildings in canyons

This study formulated a new index for evaluating both the air quality and wind comfort induced by building openings at the pedestrian level of street canyons. The air pollutant concentrations and wind velocities induced by building openings were predicted by a series of CFD simulations using ANSYS Fluent software based on standard k-ɛ model. The types of opening configurations investigated inside isolated and non-isolated canyons included separations, voids and permeable elements. It was found that openings with permeability values of 10% were adequate for improving the air quality and wind comfort conditions for pedestrians after considering the reduction in development floor areas. Openings were effective in improving the air quality in isolated canyons and different types of opening configurations were suggested for different street aspect ratios. On the contrary, openings were not always found effective for non-isolated canyons if there were pollutant sources in adjacent street canyons. As such, it would also be recommended introducing openings to adjacent canyons along with openings to the target canyons. The formulated index can help city planners and building designers to strike an optimal balance between air quality and wind comfort for pedestrians when designing and planning buildings inside urban streets and thus promoting urban environmental sustainability.

Characterization and adsorption of Lactobacillus virulent phage P1

Bacteriophage infection of lactic acid bacteria is considered an important problem worldwide in the food fermentation industry, as it may produce low quality or unsafe foods, cause fermentation failure, and result in economic losses. To increase current knowledge on the properties of Lactobacillus virulent phages, we evaluated the effect of divalent cations, temperature, pH, and chloramphenicol on the adsorption ability of Lactobacillus virulent phage P1. Phage P1 was isolated from the abnormal fermentation liquid of Lactobacillus plantarum IMAU10120. The results showed that this phage belonged to the Siphoviridae family. The latent period of this phage was 45min, and the burst time was 90min. Burst size was 132.88±2.37 phage counts expressed per milliliter per infective center. This phage showed good tolerance at different temperatures, but incubation at 50°C only affected its adsorption. Adsorption rate reached a maximum value between 30 and 42°C. A high adsorption value of phage infectivity was obtained from pH 6 to 8. Moreover, calcium ions promoted and increased the adsorption capacity of phage P1, but magnesium ions had negative effects. Chloramphenicol had no effect on phage adsorption. This study increased current knowledge on the characterization and biological aspects of Lactobacillus virulent phages, and may provide some basic information that can be used to design successful antiphage strategies in the food industry.

[Correlation between susceptibility weighted imaging manifestation and serum cystatin C for delayed graft function]

OBJECTIVE

To explore the correlation between susceptibility weighted imaging (SWI) manifestation and serum cystatin C level for delayed graft function (DGF).

METHODS

The conventional MRI, SWI and serum cystatin C of 27 cases with DGF in nephrotransplantation center in Third Affiliated Hospital of Suzhou University from September 2014 and August 2015 were retrospectively analyzed.By contrasting conventional MRI images of transplanted kidney in DGF, the imaging manifestations of benign tumors such as cysts and angiomyolipomas were excluded on SWI images, and then making the renal cortex as the reference, if the abnormal signal lesions were found in the transplanted kidney, the location and signal intensity would be analyzed. The differences in serum cystatin C level between DGF groups without and with abnormal signal lesions were compared by using independent-sample t-test.The correlation between SWI manifestation and serum cystatin C level for DGF was assessed with Spearman rank correlation analysis.

RESULTS

A total of 15 cases were found without abnormal signal lesions and the average value of their serum cystatin C level was (2.92±0.44) mg/L.A total of 12 cases were found with abnormal low signal lesions located at junctional zone between cortex and medulla, and the average value of their serum cystatin C level was (6.91±0.96) mg/L. The differences in serum cystatin C level between the two DGF groups were statistically significant (t=-4.040, P=0.000). There was a positive correlation between the abnormal low signal lesions on SWI and serum cystatin C level (r=0.660, P=0.000).

CONCLUSION

The status of renal function impairment could be reflected by being with or without abnormal signal lesions on SWI. A relatively big renal function impairment may be predicted by the appearance of abnormal low signal lesions at junctional zone between cortex and medulla on SWI.

Central composite design approach towards optimization of super activated carbons from bamboo for hydrogen storage

Super activated carbons were developed from moso bamboo and central composite design was used to determine optimum responses by investigating the influence of activation parameters, weight ratio of KOH/precursor (W) and activation temperature (T).

Effects of silencing MTA1 gene by RNA interference on invasion and metastasis of endometrial carcinoma

OBJECTIVE

The study aimed at the silence effect of MAT1 gene and proteins in Ishikawa cell of human endometrial carcinoma cell line through RNAi mediated by siRNA and also discussed the effect of MTA1 gene silence on the invasion and metastasis of endometrial carcinoma.

MATERIALS AND METHODS

According to the principle of designing siRNA sequence, siRNA aiming at MTA1 gene (MTA1-siRNA) and siRNA used for negative control (Control-siRNA) were designed and synthesized and Ishikawa cell was transfected by transfection reagents. RT-PCR method as well as western blot was used, respectively, to detect the MTA1 mRNA and protein expression of stably transfected cells. Transwell method and scarification experiment were adopted to detect the invasion and metastasis of Ishikawa cells.

RESULTS

The expression results of MTA1 on the levels of mRNA and protein showed that the expression level in transfected MTA1-siRNA group was obviously lower than that in non-transfected group and transfected control-siRNA group (p <0.05), while there was no significant difference between non-transfected group and transfected control-siRNA group (p > 0.05). Effective interference on the expression of MTA1 gene remarkably lowered the invasion and metastasis of endometrial carcinoma Ishikawa cells.

CONCLUSION

RNAi aiming at MTA1 can effectively inhibit the expression of MTA1 in endometrial carcinoma Ishikawa cells and the effective silence of MTA1 can weaken the invasion and metastasis of Ishikawa cells, which provides a new strategy for gene therapy of endometrial carcinoma and an experimental basis for inhibiting the invasion and metastasis of endometrial carcinoma.

Can tumor regression grade influence survival outcome in ypT3 rectal cancer?

PURPOSE

Locally advanced rectal cancer (LARC) patients achieving ypT3 status following neoadjuvant chemoradiation are considered to have poor response with minimal downstaging. However, residual cancer cell amounts vary in the subserosa/perirectal fat. Tumor regression grading (TRG) is an evaluation method based on the proportion of fibrosis and residual cancer cells. The aim of this study is to assess the influence of TRG in ypT3 rectal cancer patients who received neoadjuvant chemoradiation.

METHODS

We retrospectively reviewed 325 LARC patients who received neoadjuvant chemoradiation and surgery. TRG scores were recorded by two independent pathologists. Among these patients, 143 were staged as ypT3. We analyzed TRG and other clinicopathological factors and their relationship with survival outcome including overall survival (OS) and disease-free survival (DFS).

RESULTS

Among 143 ypT3 patients, 44 (30.8 %) were TRG1, 84 (58.7 %) were TRG2 and 15 (10.5 %) were TRG3. Seventy-nine (55.3 %) of these patients had metastatic lymph nodes. In univariate analysis, TRG was not associated with DFS (TRG2 vs TRG1, P = 0.852; TRG3 vs TRG1, P = 0.593) or OS (TRG2 vs TRG1, P = 0.977; TRG3 vs TRG1, P = 0.665). Palliative surgery (HR 3.845; 95 % CI 1.670-8.857; P = 0.002) and metastatic lymph nodes after surgery (HR 5.894; 95 % CI 1.142-3.48; P = 0.015) were significantly associated with decreased DFS, while palliative surgery was the only factor associated with worse OS (HR 6.011; 95 % CI 2.150-16.810; P = 0.001). Palliative surgery (HR 3.923; 95 % CI 1.696-9.073; P = 0.001) and metastatic lymph nodes (HR 2.011; 95 % CI 1.152-3.512; P = 0.014) also showed prognostic significance for DFS in multivariate analysis.

CONCLUSIONS

Residual cancer cells evaluated by TRG score after neoadjuvant chemoradiation do not influence survival outcome in ypT3 rectal cancer patients. However, lymph node status is a significant prognostic factor in ypT3 patients.