TFPI‐2 silencing increases tumour progression and promotes metalloproteinase 1 and 3 induction through tumour‐stromal cell interactions

Tissue factor pathway inhibitor‐2 (TFPI‐2) is a potent inhibitor of plasmin which activates matrix metalloproteinases (MMPs) involved in degradation of the extracellular matrix. Its secretion in the tumour microenvironment makes TFPI‐2 a potential inhibitor of tumour invasion and metastasis. As demonstrated in aggressive cancers, TFPI‐2 is frequently down‐regulated in cancer cells, but the mechanisms involved in the inhibition of tumour progression remained unclear. We showed in this study that stable TFPI‐2 down‐regulation in the National Cancer Institute (NCI)‐H460 non‐small cell lung cancer cell line using specific micro interfering micro‐interfering RNA promoted tumour progression in a nude mice orthotopic model that resulted in an increase in cell invasion. Moreover, TFPI‐2 down‐regulation enhanced cell adhesion to collagen IV and laminin via an increase in α₁ integrin on cell surface, and increased MMP expression (mainly MMP‐1 and ‐3) contributing to cancer cell invasion through basement membrane components. This study also reveals for the first time that pulmonary fibroblasts incubated with conditioned media from TFPI‐2 silencing cancer cells exhibited increased expression of MMPs, particularly MMP‐1, ‐3 and ‐7, that are likely involved in lung cancer cell invasion through the surrounding stromal tissue, thus enhancing formation of metastases.     

A strategy for clone selection under different production conditions

Top performing clones have failed at the manufacturing scale while the true best performer may have been rejected early in the screening process. Therefore, the ability to screen multiple clones in complex fed-batch processes using multiple process variations can be used to assess robustness and to identify critical factors. This dynamic ranking of clones' strategy requires the execution of many parallel experiments than traditional approaches. Therefore, this approach is best suited for micro-bioreactor models which can perform hundreds of experiments quickly and efficiently. In this study, a fully monitored and controlled small scale platform was used to screen eight CHO clones producing a recombinant monoclonal antibody across several process variations, including different feeding strategies, temperature shifts and pH control profiles. The first screen utilized 240 micro-bioreactors were run for two weeks for this assessment of the scale-down model as a high-throughput tool for clone evaluation. The richness of the outcome data enable to clearly identify the best and worst clone as well as process in term of maximum monoclonal antibody titer. The follow-up comparison study utilized 180 micro-bioreactors in a full factorial design and a subset of 12 clone/process combinations was selected to be run parallel in duplicate shake flasks. Good correlation between the micro-bioreactor predictions and those made in shake flasks with a Pearson correlation value of 0.94. The results also demonstrate that this micro-scale system can perform clone screening and process optimization for gaining significant titer improvements simultaneously. This dynamic ranking strategy can support better choices of production clones.     

Over-expression of the miRNA cluster at chromosome 14q32 in the alcoholic brain correlates with suppression of predicted target mRNA required for oligodendrocyte proliferation

We examined miRNA expression from RNA isolated from the frontal cortex (Broadman area 9) of 9 alcoholics (6 males, 3 females, mean age 48 years) and 9 matched controls using both the Affymetrix GeneChip miRNA 2.0 and Human Exon 1.0 ST Arrays to further characterize genetic influences in alcoholism and the effects of alcohol consumption on predicted target mRNA expression. A total of 12 human miRNAs were significantly up-regulated in alcohol dependent subjects (fold change ≥ 1.5, false discovery rate (FDR) ≤ 0.3; p < 0.05) compared with controls including a cluster of 4 miRNAs (e.g., miR-377, miR-379) from the maternally expressed 14q32 chromosome region. The status of the up-regulated miRNAs was supported using the high-throughput method of exon microarrays showing decreased predicted mRNA gene target expression as anticipated from the same RNA aliquot. Predicted mRNA targets were involved in cellular adhesion (e.g., THBS2), tissue differentiation (e.g., CHN2), neuronal migration (e.g., NDE1), myelination (e.g., UGT8, CNP) and oligodendrocyte proliferation (e.g., ENPP2, SEMA4D1). Our data support an association of alcoholism with up-regulation of a cluster of miRNAs located in the genomic imprinted domain on chromosome 14q32 with their predicted gene targets involved with oligodendrocyte growth, differentiation and signaling.     

Relationship between genetic variant in pre-microRNA-146a and genetic predisposition to temporal lobe epilepsy: A case–control study

There is evidence that inflammatory mechanisms play a role in the pathogenesis of temporal lobe epilepsy (TLE). MicroRNAs (miRNAs), a class of small non-coding endogenous RNAs, which negatively regulate target gene expression, have shown different expression patterns in immune diseases. Recently, several miRNAs have been found to be differentially expressed in animal models of TLE. To understand the role of miRNAs in the molecular mechanisms of TLE, we sought to determine whether genetic variant rs2910164 in the pre-miR-146a gene could influence susceptibility to TLE in an Italian population sample. A cohort of 357 TLE patients and 543 healthy controls were genotyped for detection of this SNP using TaqMan Allelic Discrimination assays, on an Applied Biosystems PCR platform. Analysis of genotype or allelic frequencies between patients and controls showed no statistically significant differences (p = 0.536 and p = 0.361 respectively). Moreover, such variant did not influence the main clinical characteristics of TLE. In conclusion, our data suggest that the rs2910164 variant in the pre-miR-146a gene is unlikely to influence significantly the risk of developing TLE or its severity.     

On dental wear, dental work, and oral health in the type specimen (LB1) of Homo floresiensis

The claim that the lower left first mandibular molar of LB1, the type specimen of Homo floresiensis, displays endodontic work, and a filling is assessed by digital radiography and micro-CT scanning. The M(1) tooth crown is heavily worn and exhibits extensive dentine exposure that is stained white, but there is no trace of endodontic treatment or a dental filling in this Indonesian fossil dated to 17.1-19.0 kya. Dental calculus (commonly observed in foragers) is present on the teeth of LB1, but there are no observable caries. The pattern of dental attrition in the mandibles of both LB1/2 and LB6/1 (moderate to extensive flat wear across the entire arch) is consistent with that seen in Plio-Pleistocene Homo fossils and in modern hunter-gatherers, and is not typical of most agriculturalists. We conclude that the dental-work and farming hypotheses are falsified and therefore irrelevant to the debate over the taxonomy and phylogeny of H. floresiensis.     

Analysis of two pharmacodynamic biomarkers using acoustic micro magnetic particles on the ViBE bioanalyzer

Pharmacodynamic responses to drug treatment are often used to confirm drug-on-target biological responses. Methods ranging from mass spectrometry to immunohistochemistry exist for such analyses. By far, the most extensively used methodologies employ antigen-specific antibodies for detection (at a minimum) and, in some cases, target quantitation as well. Using a novel frequency-modulating technology from BioScale called acoustic micro magnetic particle (AMMP) detection, two pathway biomarkers were chosen for pharmacodynamic analysis and compared with either AlphaScreen or LI-COR Western blot assays. For these studies, pharmacodynamic biomarkers for both proteasome and phosphoinositol 3-kinase inhibition were used. Our results show clearly that the BioScale technology is a robust and rapid method for measuring recombinant standards or endogenously derived proteins from both tissue culture and mouse xenograft tumor lysates. Moreover, the sensitivity obtained with the BioScale platform compares favorably with LI-COR Western blot and AlphaScreen technologies. Furthermore, the use of the ViBE Bioanalyzer eliminates the labor-intensive effort of Western blot analysis and is devoid of the optical and other endogenous interfering substances derived from lysates of xenograft tumors typically observed with AlphaScreen.     

Flow dynamics within a bioreactor for tissue engineering by residence time distribution analysis combined with fluorescence and magnetic resonance imaging to investigate forced permeability and apparent diffusion coefficient in a perfusion cell culture chamber

This study reveals that residence time distribution (RTD) analysis with pH monitoring after acid bolus injection can be used to globally study the flow dynamics of a perfusion bioreactor, while fluorescence microscopy and magnetic resonance imaging (MRI) were used to locally investigate mass transport within a hydrogel scaffold seeded or not with cells. The bioreactor used in this study is a close‐loop tubular reactor. A dispersion model in one dimension has been used to describe the non‐ideal behavior of the reactor. From open‐loop experiments (single‐cycle analysis), the presence of stagnant zones and back mixing were observed. The impact of the flow rate, the compliance chamber volume and mixing were investigated. Intermediate flows (30, 45, 60, and 90 mL min⁻¹) had no effect over RTD function expressed in reduced time (θ). Lower flow rates (5 and 15 mL min⁻¹) were associated to smaller extent of dispersion. The compliance chamber volume greatly affected the dynamics of the RTD function, while the effects of mixing and flow were small to non‐significant. An empirical equation has been proposed to localize minima of the RTD function and to predict Pe_r. Finally, cells seeded in a gelatin gel at a density of 800,000 cells mL⁻¹ had no effect over the permeability and the apparent diffusion coefficient, as revealed by fluorescent microscopy and MRI experiments. Biotechnol. Bioeng. 2011;108: 2488–2498. © 2011 Wiley Periodicals, Inc.     

Perspectives and challenges of micro/nanoplastics‐induced toxicity with special reference to phytotoxicity

Plastic pollution has become a global concern for ecosystem health and biodiversity conservation. Concentrations of plastics are manifold higher in the terrestrial system than the aquatic one. Micro/nanoplastics (M/NP) have the ability to alter soil enzymatic system, soil properties and also affect soil borne microorganisms and earthworms. Despite, the knowhow regarding modulatory effects of plastics are acquired from the study on aquatic system and reports on their phytotoxic potentials are limited. The presence of cell wall that could restrict M/NP invasion into plant roots might be the putative cause of this limitation. M/NP inhibit plant growth, seed germination and gene expression; and they also induce cytogenotoxicity by aggravating reactive oxygen species generation. Dynamic behavior of cell wall; the pores formed either by cell wall degrading enzymes or by plant–pathogen interactions or by mechanical injury might facilitate the entry of into roots M/NP. This review also provides a possible mechanism of large sized microplastics‐induced phytotoxicity especially for those that cannot pass through cell wall pores. As M/NP affect soil microbial community and soil parameters, it is hypothesized that they could have the potential to affect N₂ fixation and research should be conducted in this direction. Reports on M/NP‐induced toxicity mainly focused only on one polymer type (polystyrene) in spite of the toxicological relevancies of other polymer types like polyethylene, polypropylene etc. So, the assessment of phytotoxic potential of M/NP should be done using other plastic polymers in real environment as they are known to intract with other environmental stressors as well as can alter the the soil–microbe–plant interaction.     

Radiation‐induced myocardial fibrosis: Mechanisms underlying its pathogenesis and therapeutic strategies

Radiation‐induced myocardial fibrosis (RIMF) is a potentially lethal clinical complication of chest radiotherapy (RT) and a final stage of radiation‐induced heart disease (RIHD). RIMF is characterized by decreased ventricular elasticity and distensibility, which can result in decreased ejection fraction, heart failure and even sudden cardiac death. Together, these conditions impair the long‐term health of post‐RT survivors and limit the dose and intensity of RT required to effectively kill tumour cells. Although the exact mechanisms involving in RIMF are unclear, increasing evidence indicates that the occurrence of RIMF is related to various cells, regulatory molecules and cytokines. However, accurately diagnosing and identifying patients who may progress to RIMF has been challenging. Despite the urgent need for an effective treatment, there is currently no medical therapy for RIMF approved for routine clinical application. In this review, we investigated the underlying pathophysiology involved in the initiation and progression of RIMF before outlining potential preventative and therapeutic strategies to counter this toxicity.     

Highly Elastic Binder for Improved Cyclability of Nickel‐Rich Layered Cathode Materials in Lithium‐Ion Batteries

Nickel‐rich layered cathode materials are predominantly used for lithium‐ion batteries intended for electric vehicles owing to their high specific capacities and minimal use of high‐cost cobalt. The intrinsic drawbacks of nickel‐rich layered cathode materials with regard to cycle life and safety have largely been addressed by doping and by applying surface coatings. Here, it is reported that a highly elastic binder, namely spandex, can overcome the problems of nickel‐rich layered cathode materials and improve their electrochemical properties drastically. The high elasticity of spandex allows it to uniformly coat LiNi_0.8Co_0.1Mn_0.1O₂ particles via shear force during slurry mixing to protect the particles from undesired interfacial reactions during cycling. The uniform coating of spandex, together with its hydrogen bonding interaction with LiNi_0.8Co_0.1Mn_0.1O₂, leads to enhanced particle‐to‐particle interaction, which has multiple advantages, such as high loading capability, superior rate and cycling performance, and low binder content. This study highlights the promise of elastic binders to meet the ever‐challenging criteria with respect to nickel‐rich cathode materials in cells targeting electric vehicles.