Intermediate filaments: a role in epithelial polarity

Intermediate filaments have long been considered mechanical components of the cell that provide resistance to deformation stress. Practical experimental problems, including insolubility, lack of good pharmacological antagonists, and the paucity of powerful genetic models have handicapped the research of other functions. In single-layered epithelial cells, keratin intermediate filaments are cortical, either apically polarized or apico-lateral. This review analyzes phenotypes of genetic manipulations of simple epithelial cell keratins in mice and Caenorhabditis elegans that strongly suggest a role of keratins in apico-basal polarization and membrane traffic. Published evidence that intermediate filaments can act as scaffolds for proteins involved in membrane traffic and signaling is also discussed. Such a scaffolding function would generate a highly polarized compartment within the cytoplasm of simple epithelial cells. While in most cases mechanistic explanations for the keratin-null or overexpression phenotypes are still missing, it is hoped that investigators will be encouraged to study these as yet poorly understood functions of intermediate filaments.     

PhotoMEA: an opto-electronic biosensor for monitoring in vitro neuronal network activity

PhotoMEA is a biosensor useful for the analysis of an in vitro neuronal network, fully based on optical methods. Its function is based on the stimulation of neurons with caged glutamate and the recording of neuronal activity by Voltage-Sensitive fluorescent Dyes (VSD). The main advantage is that it will be possible to stimulate even at sub-single neuron level and to record with high resolution the activity of the entire network in the culture. A large-scale view of neuronal intercommunications offers a unique opportunity for testing the ability of drugs to affect neuronal properties as well as alterations in the behaviour of the entire network. The concept and a prototype for validation is described here in detail.     

Taurine supplementation in conjunction with exercise modulated cytokines and improved subcutaneous white adipose tissue plasticity in obese women

Amino Acids - Interventions that can modulate subcutaneous white adipose tissue (scWAT) function, such as exercise training and nutritional components, like taurine, modulate the inflammatory...     

Investigation of blood parasites of pygoscelid penguins at the King George and Elephant Islands, South Shetlands Archipelago, Antarctica

Parasites may adversely affect the breeding success and survival of penguins, potentially hampering the viability of their populations. We examined 161 pygoscelid penguins (3 Pygoscelis adeliae, 98 Pygoscelis antarcticus, and 60 Pygoscelis papua) at the South Shetlands Archipelago during the 2010–2011 summer; blood smears were examined for 64 penguins (2 P. adeliae, 18 P. antarcticus, and 44 P. papua), and a PCR test targeting Haemoproteus sp. and Plasmodium sp. was applied for 37 penguins (2 P. adeliae, 17 P. antarcticus, 19 P. papua). No blood parasites were observed, and all PCR tests were negative, leukocyte profiles were similar to those reported in other studies for wild pygoscelid penguins, and all penguins were in good body condition and had no external signs of disease. One specimen of chewing lice (Austrogoniodes sp.) was recorded in one P. antarcticus at King George Island. Ticks (Ixodes uriae) were not observed on the penguins, but were found on the ground near P. antarcticus nests at King George Island. The absence of avian blood parasites in Antarctic penguins is thought to result from the absence of competent invertebrate hosts in the climatic conditions. Predicted climate changes may redefine the geographic distribution of vector-borne pathogens, and therefore, the occurrence of blood parasites and their invertebrate hosts should be monitored regularly in Antarctic birds, particularly in the northernmost Antarctic Peninsula.     

Value of a newly sequenced bacterial genome

Next-generation sequencing(NGS) technologies have made high-throughput sequencing available to medium- and small-size laboratories, culminating in a tidal wave of genomic information. The quantity of sequenced bacterial genomes has not only brought excitement to the field of genomics but also heightened expectations that NGS would boost antibacterial discovery and vaccine development. Although many possible drug and vaccine targets have been discovered, the success rate of genome-based analysis has remained below expectations. Furthermore, NGS has had consequences for genome quality, resulting in an exponential increase in draft(partial data) genome deposits in public databases. If no further interests are expressed for a particular bacterial genome, it is more likely that the sequencing of its genome will be limited to a draft stage, and the painstaking tasks of completing the sequencing of its genome and annotation will not be undertaken. It is important to know what is lost when we settle for a draft genome and to determine the "scientific value" of a newly sequenced genome. This review addresses the expected impact of newly sequenced genomes on antibacterial discovery and vaccinology. Also, it discusses the factors that could be leading to the increase in the number of draft deposits and the consequent loss of relevant biological information.     

High-Grade Cervical Lesions Among Women Attending A Reference Clinic In Brazil: Associated Factors And Comparison Among Screening Methods

Background

Although screening for cervical cancer is recommended for women in most countries, the incidence of cervical cancer is greater in developing countries. Our goal was to determine the prevalence and factors associated with high-grade lesions/cervical cancer among women attending a reference clinic in Brazil and evaluate the correlation of histology with cytology, colposcopy and the high-risk HPV (HR-HPV) tests.

Methods

A cross-sectional study of women attending a colposcopy clinic was carried out. The patients were interviewed to collect demographic, epidemiological and clinical data. Specimens were collected for cervical cytology, Chlamydia trachomatis and HPV testing using the Hybrid Capture (HC) and PCR tests. Colposcopy was performed for all patients and biopsy for histology when cell abnormalities or cervical intraepithelial neoplasia (CIN) were present.

Results

A total of 291 women participated in the study. The median age was 38 years (DIQ: 30–48 years). The prevalence of histologically confirmed high-grade lesions/cervical cancer was 18.2% (95%, CI: 13.8%–22.6%), with 48 (16.5%) cases of CIN-2/CIN-3 and 5 (1.7%) cases of invasive carcinoma. In the final logistic regression model, for ages between 30 and 49 years old [OR = 4.4 (95%: 1.01–19.04), history of smoking [OR = 2.4 (95%, CI: 1.14–5.18)], practice of anal intercourse [OR = 2.4 (95%, CI: 1.10–5.03)] and having positive HC test for HR-HPV [OR = 11.23 (95%, CI: 4 0.79–26, 36)] remained independently associated with high-grade lesions/cervical cancer. A total of 64.7% of the cases CIN-3\Ca in situ were related to HPV-16. Non-oncogenic HPV were only found in CIN-1 biopsy results. Compared to histology, the sensitivity of cytology was 31.8%, the specificity 95.5%; the sensitivity of colposcopy for high-grade lesions/cervical cancer was 51.0%, specificity was 91.4% and the concordance with HPV testing was high.

Conclusions

The results confirm an association of HR-HPV with precursor lesions for cervical cancer. These data emphasize that cytological screening to detect precursor lesions is still important in some regions and that HR-HPV should be included for screening.     

Quantitative and Qualitative Assessment of Yttrium-90 PET/CT Imaging

Yttrium-90 is known to have a low positron emission decay of 32 ppm that may allow for personalized dosimetry of liver cancer therapy with ⁹⁰Y labeled microspheres. The aim of this work was to image and quantify ⁹⁰Y so that accurate predictions of the absorbed dose can be made. The measurements were performed within the QUEST study (University of Sydney, and Sirtex Medical, Australia). A NEMA IEC body phantom containing 6 fillable spheres (10–37 mm ∅) was used to measure the ⁹⁰Y distribution with a Biograph mCT PET/CT (Siemens, Erlangen, Germany) with time-of-flight (TOF) acquisition. A sphere to background ratio of 8∶1, with a total ⁹⁰Y activity of 3 GBq was used. Measurements were performed for one week (0, 3, 5 and 7 d). he acquisition protocol consisted of 30 min-2 bed positions and 120 min-single bed position. mages were reconstructed with 3D ordered subset expectation maximization (OSEM) and point spread function (PSF) for iteration numbers of 1–12 with 21 (TOF) and 24 (non-TOF) subsets and CT based attenuation and scatter correction. Convergence of algorithms and activity recovery was assessed based on regions-of-interest (ROI) analysis of the background (100 voxels), spheres (4 voxels) and the central low density insert (25 voxels). For the largest sphere, the recovery coefficient (RC) values for the 30 min –2-bed position, 30 min-single bed and 120 min-single bed were 1.12±0.20, 1.14±0.13, 0.97±0.07 respectively. For the smaller diameter spheres, the PSF algorithm with TOF and single bed acquisition provided a comparatively better activity recovery. Quantification of Y-90 using Biograph mCT PET/CT is possible with a reasonable accuracy, the limitations being the size of the lesion and the activity concentration present. At this stage, based on our study, it seems advantageous to use different protocols depending on the size of the lesion.     

Increased Migration of Human Mesenchymal Stromal Cells by Autocrine Motility Factor (AMF) Resulted in Enhanced Recruitment towards Hepatocellular Carcinoma

Background and Aims

Several reports described the migration of human mesenchymal stromal cells (MSCs) towards tumor-released factors. Autocrine motility factor (AMF) is produced by several tumors including hepatocellular carcinoma (HCC). The aim of this study was to analyze AMF involvement on MSC migration towards human HCC.

Methods

Production of AMF by HCC tumors was evaluated by western analysis. The effects of AMF on MSCs from different sources (bone marrow, adipose tissue and perivascular cells from umbilical cord) were analyzed using in vitro migration assay; metalloproteinase 2 (MMP2) activity and expression of critical genes were studied by zymography and qRT-PCR, respectively. To assess AMF involvement on the in vivo MSC migration, noninvasive fluorescence imaging was performed. To test the effect of AMF-primed MSCs on tumor development, in vitro proliferation and spheroids growth and in vivo tumor volume were evaluated.

Results

AMF produced by HCC was found to induce migration of different MSCs in vitro and to enhance their MMP2 activity. Stimulation of MSCs with recombinant AMF (rAMF) also induced the in vitro adhesion to endothelial cells in coincidence with changes in the expression levels of MMP3, AMF receptor, caveolin-1, and -2 and GDI-2. Importantly, stimulation of MSCs with rAMF increased the in vivo migration of MSCs towards experimental HCC tumors. AMF-priming of MSCs did not induce a pro-tumorigenic effect on HCC cells neither in vivo nor in vitro.

Conclusion

AMF plays a role in MSC recruitment towards HCC. However, its ability to increase MSC migration to HCC for therapeutic purposes merits further evaluation.