The culture of HaCaT cells on liquid substrates is mediated by a mechanically strong liquid–liquid interface

The mechanical properties of naturally-derived matrices and biomaterials are thought to play an important role in directing cell adhesion, spreading, motility, proliferation and differentiation. However, recent reports have indicated that cells may respond to local nanoscale physical cues, rather than bulk mechanical properties. We had previously reported that primary keratinocytes and mesenchymal stem cells did not seem to respond to the bulk mechanical properties of poly(dimethyl siloxane) (PDMS) substrates. In this study, we examine the mechanical properties of weakly crosslinked PDMS substrates and observe a liquid-like behaviour, with complete stress relaxation. We then report the observation that HaCaT cells, an epidermal cell line, proliferate readily at the surface of uncrosslinked liquid PDMS, as well as on low viscosity (0.77 cSt) fluorinated oil. These results are surprising, considering current views in the field of mechanotransduction on the importance of bulk mechanical properties, but we find that strong mechanical interfaces, presumably resulting from protein assembly, are formed at liquid–liquid interfaces for which cell adhesion and proliferation are observed. Hence our results suggest that cells sense the nanoscale mechanical properties of liquid–liquid interfaces and that such physical cues are sufficient to sustain the proliferation of adherent cells.

Meta-analysis of radiofrequency ablation for treating the local recurrence of thyroid cancers

OBJECTIVES

Our aim was to evaluate the efficacy of ultrasound-guided radiofrequency ablation (RFA) for localized recurrent thyroid cancers.

METHODS

We did a systematic review and meta-analysis of the scientific literature by searching the PubMed, Embase, Web of Science,Scopus and the Cochrane Library up to November 26, 2015. We assessed the pooled standard mean difference (SMD) of nodule volume, largest diameter and serum thyroglobulin (Tg) level by comparing pre-RFA with post-RFA using fixed or random-effects model. The Newcastle-Ottawa Scale was used to evaluate the methodological quality of the included studies, risk of bias in the selective populations, comparability of groups and exposure.

RESULTS

We finally identified nine articles including 189 patients (male: 54 and female: 135) with 255 tumor lesions, who underwent ultrasound (US)-guided RFA beyond the mean 6 months of follow-up. The results showed that tumor volume (SWD: 0.77, 95 % CI: 0.57-0.97, I (2) = 25.9 %, p = 0.231), largest diameter (SWD: 1.56, 95 % CI: 0.94-2.17, I (2) = 82.6 %, p < 0.001) and Tg level (SWD: 0.52, 95 % CI: 0.30-0.73, I (2) = 0 %, p = 0.493) were decreased and no significant publication bias was detectable.

CONCLUSIONS

The pooled data indicated that the prognosis improved for patients with localized recurrent thyroid cancers and RFA is a promising treatment for these patients with infeasible surgery.

Differential regulation of skin fibroblasts for their TGF-β1-dependent wound healing activities by biomimetic nanofibers

Nanofibers with different compositions differentially regulate fibroblast phenotypes in a TGF-β1 rich milieu through the integrin-mediated TGF-β1/Smad signaling pathway.

Protective effects of tumor necrosis factor-α blockade by adalimumab on articular cartilage and subchondral bone in a rat model of osteoarthritis

We aimed to investigate the effects of an anti-tumor necrosis factor-α antibody (ATNF) on cartilage and subchondral bone in a rat model of osteoarthritis. Twenty-four rats were randomly divided into three groups: sham-operated group (n=8); anterior cruciate ligament transection (ACLT)+normal saline (NS) group (n=8); and ACLT+ATNF group (n=8). The rats in the ACLT+ATNF group received subcutaneous injections of ATNF (20 μg/kg) for 12 weeks, while those in the ACLT+NS group received NS at the same dose for 12 weeks. All rats were euthanized at 12 weeks after surgery and specimens from the affected knees were harvested. Hematoxylin and eosin staining, Masson's trichrome staining, and Mankin score assessment were carried out to evaluate the cartilage status and cartilage matrix degradation. Matrix metalloproteinase (MMP)-13 immunohistochemistry was performed to assess the cartilage molecular metabolism. Bone histomorphometry was used to observe the subchondral trabecular microstructure. Compared with the rats in the ACLT+NS group, histological and Mankin score analyses showed that ATNF treatment reduced the severity of the cartilage lesions and led to a lower Mankin score. Immunohistochemical and histomorphometric analyses revealed that ATNF treatment reduced the ACLT-induced destruction of the subchondral trabecular microstructure, and decreased MMP-13 expression. ATNF treatment may delay degradation of the extracellular matrix via a decrease in MMP-13 expression. ATNF treatment probably protects articular cartilage by improving the structure of the subchondral bone and reducing the degradation of the cartilage matrix.

320 Gb/s Nyquist OTDM received by polarization-insensitive time-domain OFT

We have demonstrated the generation of a 320 Gb/s Nyquist-OTDM signal by rectangular filtering on an RZ-OTDM signal with the filter bandwidth (320 GHz) equal to the baud rate (320 Gbaud) and the reception of such a Nyquist-OTDM signal using polarization-insensitive time-domain optical Fourier transformation (TD-OFT) followed by passive filtering. After the time-to-frequency mapping in the TD-OFT, the Nyquist-OTDM signal with its characteristic sinc-shaped time-domain trace is converted into an orthogonal frequency division multiplexing (OFDM) signal with sinc-shaped spectra for each subcarrier. The subcarrier frequency spacing of the converted OFDM signal is designed to be larger than the transform-limited case, here 10 times greater than the symbol rate of each subcarrier. Therefore, only passive filtering is needed to extract the subcarriers of the converted OFDM signal. In addition, a polarization diversity scheme is used in the four-wave mixing (FWM) based TD-OFT, and less than 0.5 dB polarization sensitivity is demonstrated in the OTDM receiver.

All-optical OFDM demultiplexing by spectral magnification and band-pass filtering

We propose a simple OFDM receiver allowing for the use of standard WDM receivers to receive spectrally advanced OFDM signals. We propose to spectrally magnify the optical-OFDM super-channels using a spectral telescope consisting of two time-lenses, which enables reduced inter-carrier-interference in subcarrier detection by simple band-pass filtering. A demonstration on an emulated 100 Gbit/s DPSK optical-OFDM channel shows improved sensitivities after 4-times spectral magnification.

Erratum: Epigenetic silencing of miR-34a in human prostate cancer cells and tumor tissue specimens can be reversed by BR-DIM treatment

Androgen Receptor (AR) signaling is critically important during the development and progression of prostate cancer (PCa). The AR signaling is also important in the development of castrate resistant prostate cancer (CRPC) where AR is functional even after androgen deprivation therapy (ADT); however, little is known regarding the transcriptional and functional regulation of AR in PCa. Moreover, treatment options for primary PCa for preventing the occurrence of CRPC is limited; therefore, novel strategy for direct inactivation of AR is urgently needed. In this study, we found loss of miR-34a, which targets AR, in PCa tissue specimens, especially in patients with higher Gleason grade tumors, consistent with increased expression of AR. Forced over-expression of miR-34a in PCa cell lines led to decreased expression of AR and prostate specific antigen (PSA) as well as the expression of Notch-1, another important target of miR-34a. Most importantly, BR-DIM intervention in PCa patients prior to radical prostatectomy showed reexpression of miR-34a, which was consistent with decreased expression of AR, PSA and Notch-1 in PCa tissue specimens. Moreover, BR-DIM intervention led to nuclear exclusion both in PCa cell lines and in tumor tissues. PCa cells treated with BR-DIM and 5-aza-dC resulted in the demethylation of miR-34a promoter concomitant with inhibition of AR and PSA expression in LNCaP and C4-2B cells. These results suggest, for the first time, epigenetic silencing of miR-34a in PCa, which could be reversed by BR-DIM treatment and, thus BR-DIM could be useful for the inactivation of AR in the treatment of PCa.[This corrects the article on p. 14 in vol. 4.].

Curcumin acts via transient receptor potential vanilloid-1 receptors to inhibit gut nociception and reverses visceral hyperalgesia

BACKGROUND

An antinociceptive effect has been reported for curcumin in animal models and in humans, but the molecular mechanisms of curcumin's effect remain undefined. In this study, we explored the possibility that curcumin inhibit visceral nociception via antagonizing the transient receptor potential vanilloid-1 (TRPV1) receptor.

METHODS

The effects of curcumin were explored using two experimental models: viscero-motor response (VMR) to colorectal distension (CRD) in rats and jejunal afferent firing in the ex vivo mouse jejunum preparations [TRPV1 knockout (KO) and wild-type mice, naive and trinitrobenzene sulfonic acid (TNBS)-treated Kunming mice]. In addition, capsaicin-induced calcium transients and whole-cell currents were examined in acutely dissociated dorsal root ganglia (DRG) neurons.

KEY RESULTS

In the anesthetized rat, curcumin (4 mg kg(-1)  min(-1) for 3 min) caused a marked and rapidly reversible inhibition of CRD-induced VMRs. In the mouse jejunum, the mesenteric afferent nerve response to ramp distension was attenuated by curcumin (3, 10 μmol L(-1) ), an effect that was significantly reduced in TRPV1 KO mice compared with wild-type (WT) controls. Moreover, in WT mice, curcumin (1-30 μmol L(-1) ) was found to inhibit the afferent responses to capsaicin in a concentration-dependent manner. Trinitrobenzene sulfonic acid-induced hypersensitivity of jejunal afferents was also attenuated by curcumin. Curcumin potently inhibited capsaicin-induced rise in intracellular calcium and inward currents in mouse or rat DRG neurons.

CONCLUSIONS & INFERENCES

Our results provide strong evidence that curcumin inhibit visceral nociception via antagonizing TRPV1 and may be a promising lead for the treatment of functional gastrointestinal diseases.

Effect of FK506 in reducing scar formation by inducing fibroblast apoptosis after sciatic nerve injury in rats

We previously demonstrated that FK506, a generally applied immunosuppressant in organ transplantation, could promote peripheral nerve regeneration through reducing scar formation. However, little is known about how FK506 reduces scar formation. Herein we investigated the influence of FK506 on fibroblast proliferation and its correlation with scar formation after sciatic nerve injury in rats, and further explored the effect of FK506 on fibroblast proliferation and apoptosis in vitro. Masson staining and immunohistochemistry revealed that scar area and fibroblast number in the nerve anastomosis of sciatic nerve-injured rats were significantly reduced after FK506 administration. The scar area had a significant positive correlation with the fibroblast number, as detected by linear correlation analysis. CCK-8 assay and flow cytometry indicated that FK506 also inhibited proliferation and induced apoptosis of fibroblasts in vitro. It was primarily phosphorylation of JNK and ERK that were activated during the apoptosis of fibroblast. Pretreatment of cells with JNK inhibitor, SP600125, or ERK inhibitor, PD98059, could inhibit FK506-induced fibroblast apoptosis, respectively. Moreover, simultaneous application of both inhibitors had additive roles in cell protection from apoptosis. These results suggest that FK506-induced fibroblast apoptosis contributes to the suppression of fibroblast proliferation and then results in the reduction of scar formation in sciatic nerve-injured rat, and that JNK and ERK are involved in FK506-induced fibroblast apoptosis.

Autologous dendritic cells combined with cytokine-induced killer cells synergize low-dose chemotherapy in elderly patients with acute myeloid leukaemia

OBJECTIVES

To investigate the possibility of culturing dendritic cells (DCs) and cytokine-induced killer (CIK) cells, obtained at initial diagnosis of AML in elderly patients, and to investigate the safety and efficacy of treatment with autologous DCs and CIK cells when administered to these patients in combination with low-dose chemo therapy.

METHODS

DCs and CIK cells obtained at initial diagnosis of AML in elderly patients were cultured and used in combination with low-dose chemo therapy to treat these patients (immunotherapy group). Elderly patients with AML treated only with low-dose chemotherapy served as the control. Before treatment and on day 7 after treatment with autologous DCs and CIK cells, T cell subsets and cytokine levels were evaluated in the immunotherapy group.

RESULTS

A total of 21 elderly patients with AML were included in the immunotherapy group and 23 in the control group. The clinical efficacy in the immunotherapy group was greater than in the control group. The percentages of T cell subsets and cytokine levels after immunotherapy treatment were significantly higher than before the treatment.

CONCLUSION

Immuno therapy with autologous DCs and CIK cells was found to be a promising candidate for treatment of AML in elderly patients.

Cell growth and protein formation on various microcarriers

A large number of microcarriers are commercially available. The capability of cells to successfully proliferate on microcarriers varies with cell lines and media. Choosing the right microcarrier for a particular cell line is more than a choice of a microcarrier. It is part of an integrated process design. A detailed picture of cell growth and product formation will not only be essential in identifying the kind of microcarrier, but also in determining other parts of the process, such as operation mode and media. Our initial screening on thirteen microcarriers showed that cultures on some microcarriers reached a low cell density but high cell-specific productivity, and high density microcarrier cultures have a low specific productivity. The result is a similar product output per unit volume and time for these two types of cultures. An ideal culture system shall have increased volumetric productivity at elevated cell density. This requires the process goal to be incorporated as early as cell line construction and screening. A high output process can then be realized through high density culture.

Long-term stable production of monocyte-colony inhibition factor (M-CIF) from CHO microcarrier perfusion cultures

Monocyte-colony inhibition factor (M-CIF) was produced in microcarrier perfusion cultures from engineered Chinese hamster ovary (CHO) cells. Three and fifteen liter microcarrier perfusion bioreactors equipped with internal spin filters were operated for over two months. Approximately 60 L and 300 L of culture filtrate were harvested from the 3L and 15L microcarrier perfusion bioreactors respectively. During the perfusion operation, cell density reached 2-6 × 10(6) cells/ml. Importantly, stable expression of M-CIF from the CHO cells under non-selection condition was maintained at a level of 4-10 mg/L. Specific productivity was maintained at 1.8-3.4 mg/billion cells/day. The ability of the recombinant CHO cells to migrate from microcarrier to microcarrier under our proprietary HGS-CHO-3 medium greatly facilitated microcarrier culture scale-up and microcarrier replenishment. Future directions for microcarrier perfusion system scale-up and process development are highlighted.