On-chip automation of cell-free protein synthesis: new opportunities due to a novel reaction mode

Many pharmaceuticals are proteins or their development is based on proteins. Cell-free protein synthesis (CFPS) is an innovative alternative to conventional cell based systems which enables the production of proteins with complex and even new characteristics. However, the short lifetime, low protein production and expensive reagent costs are still limitations of CFPS. Novel automated microfluidic systems might allow continuous, controllable and resource conserving CFPS. The presented microfluidic TRITT platform (TRITT for Transcription - RNA Immobilization & Transfer - Translation) addresses the individual biochemical requirements of the transcription and the translation step of CFPS in separate compartments, and combines the reaction steps by quasi-continuous transfer of RNA templates to enable automated CFPS. In detail, specific RNA templates with 5' and 3' hairpin structures for stabilization against nucleases were immobilized during in vitro transcription by newly designed and optimized hybridization oligonucleotides coupled to magnetizable particles. Transcription compatibility and reusability for immobilization of these functionalized particles was successfully proven. mRNA transfer was realized on-chip by magnetic actuated particle transfer, RNA elution and fluid flow to the in vitro translation compartment. The applicability of the microfluidic TRITT platform for the production of the cytotoxic protein Pierisin with simultaneous incorporation of a non-canonical amino acid for fluorescence labeling was demonstrated. The new reaction mode (TRITT mode) is a modified linked mode that fulfills the precondition for an automated modular reactor system. By continual transfer of new mRNA, the novel procedure overcomes problems caused by nuclease digestion and hydrolysis of mRNA during TL in standard CFPS reactions.

Brain tumour cells interconnect to a functional and resistant network

Astrocytic brain tumours, including glioblastomas, are incurable neoplasms characterized by diffusely infiltrative growth. Here we show that many tumour cells in astrocytomas extend ultra-long membrane protrusions, and use these distinct tumour microtubes as routes for brain invasion, proliferation, and to interconnect over long distances. The resulting network allows multicellular communication through microtube-associated gap junctions. When damage to the network occurred, tumour microtubes were used for repair. Moreover, the microtube-connected astrocytoma cells, but not those remaining unconnected throughout tumour progression, were protected from cell death inflicted by radiotherapy. The neuronal growth-associated protein 43 was important for microtube formation and function, and drove microtube-dependent tumour cell invasion, proliferation, interconnection, and radioresistance. Oligodendroglial brain tumours were deficient in this mechanism. In summary, astrocytomas can develop functional multicellular network structures. Disconnection of astrocytoma cells by targeting their tumour microtubes emerges as a new principle to reduce the treatment resistance of this disease.

Evaluation of anti-acne properties of phloretin in vitro and in vivo

OBJECTIVE

This study aimed to investigate the anti-acne properties of phloretin in vitro and in vivo.

METHODS

Anti-microbial activity against Propionibacterium acnes (P. acnes), Propionibacterium granulosum (P. granulosum) and Staphylococcus epidermidis (S. epidermidis) were observed by the minimum inhibitory concentration (MIC) and disc diffusion methods. The anti-inflammatory effects were studied in HaCaT cells based on P. acnes-induced inflammatory mediators, including PGE2 and COX-2, examined through enzyme-linked immunosorbent assay (ELISA) and luciferase reporter gene assay. Thirty healthy subjects with whiteheads participated in the clinical study. Comedo counting, and the amount of sebum and porphyrin were measured before treatment and following 4 consecutive weeks of treatment with phloretin.

RESULTS

Phloretin showed anti-microbial activities against P. acnes, P. granulosum, S. epidermidis with the MIC of 0.5, 0.5 and 0.25 mg mL(-1) , respectively. P. acnes-induced activation of the COX-2 promoter was markedly attenuated by phloretin treatment. Consistent with these results, inhibition of PGE2 production was also observed. In 1-month, placebo-controlled trials, phloretin showed clinically and statistically significant reduction of comedo counts and sebum output level. Compared to before treatment, whiteheads, blackheads, papules, sebum output level and amount of sebum and porphyrin were significantly decreased at 4 weeks in the test group.

CONCLUSIONS

This study revealed that phloretin inhibits the growth of P. acnes, P. granulosum, and S. epidermidis. In addition, we demonstrated that phloretin attenuates COX-2 and PGE2 expression during the P. acnes-induced upregulation of inflammatory signalling. Clinical studies further suggested that treatment with formulations containing phloretin confers anti-acne benefits. Based on these results, we suggest that phloretin may be introduced as a possible acne-mitigating agent.

Warfarin therapy and perioperative transfusion requirement with bleeding amount in patients undergoing cardiac surgery with cardiopulmonary bypass: a retrospective study

OBJECTIVES

The study was designed to evaluate the effect of warfarin on perioperative transfusion, bleeding and coagulation status in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB).

BACKGROUND

There were controversy about the effect of warfarin on perioperative transfusion and bleeding.

METHODS/MATERIALS

Medical records from 107 consecutive patients with atrial fibrillation (AF) on warfarin therapy undergoing cardiac surgery with cardiopulmonary bypass (CPB) from 2008 to 2013 at a single university teaching hospital were retrospectively reviewed to compare the patients on to those not on warfarin therapy in terms of perioperative transfusion requirement, postoperative 24-h bleeding amount, and coagulation status assessment using prothrombin time (PT), international normalised ratio (INR) and rotational thromboelastometry (ROTEM®).

RESULTS

Although PT/INR was significantly prolonged both before and after surgery in patients on warfarin therapy, ROTEM® data, perioperative transfusion requirement and postoperative 24-h bleeding amount (785 ± 331 vs 676 ± 303 mL, P = 0·089, respectively) were not significantly different between the patients on and those not on warfarin therapy.

CONCLUSION

In patients on warfarin therapy undergoing cardiac surgery with CPB, warfarin therapy did not significantly increase perioperative transfusion requirement and bleeding.

Autism spectrum disorders: a qualitative study of attitudes toward prenatal genetic testing and termination decisions of affected pregnancies

In the United States, prenatal genetic testing (PGT) for Autism Spectrum Disorders (ASD) is currently available via clinical genetic services. Such testing may inform parents about their unborn child's risk for ASD, prepare parents for the birth of an affected infant, and allow them to arrange for early interventions. Although PGT for autism has potential benefits, the associated ethical, legal, and social implications (ELSI) should be considered. This first qualitative study employed a hypothetical scenario to explore the attitudes toward PGT and termination decisions of 42 parents of children with ASD. Over half of the participants expressed willingness to undergo PGT for autism. Reasons included better preparation for birth, early and better treatment, termination of affected pregnancy, contribution to research, and curiosity. Of the 31 parents who were either willing or unsure about undergoing the PGT, approximately three-fourths would continue their hypothetical affected pregnancies. Explanations included preparation for birth of the child, bonding or acceptance of existing ASD-affected children, apprehensions about test limitations, and religious concerns. Parents who reported they would terminate the affected pregnancy in this hypothetical situation were primarily Asians. This study contributes to the growing understanding of the ELSI aspects of PGT in clinical practice.

Autism spectrum disorders: perceptions of genetic etiology and recurrence risk among Taiwanese parents of affected children

In Taiwan, autism spectrum disorders (ASDs) are an emerging public health concern. The ongoing scientific progress for understanding the genetic etiology of ASD makes it increasingly important to examine how parents of children with ASD perceive the causes and recurrence risk of having another child with ASD. These perceptions may influence their family planning, attitudes toward genetic services, and willingness to take their children for ASD genetic testing. However, previous studies addressing this issue were conducted primarily in Western countries. As culture might shape an individual's views of genetic/genomic disorders, this first-of-its-kind study examined the perceptions of the genetic etiology for ASD and the recurrence risk among Taiwanese parents of children affected with ASD. In-depth, semi-structured interviews were conducted among 39 parents having at least one child with ASD. Although the majority of participants believed that ASD has a genetic link, less than half perceived genetic factors as the cause of their own child's ASD. Moreover, most participants articulated their recurrence risk incorrectly. Some parents were concerned about their doctors' limited genomic competencies. To provide parents with better education, counseling, and support for making reproductive decisions, ASD-related genomic education among Taiwanese physicians is needed.