Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: part 1

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.

Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: Part 2 - spinal cord tumors, dysraphisms, diastematomyelia, and vertebral anomalies

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.

Current approaches to evaluate the function of cytotoxic T-cells in non-human primates

Cytotoxic T-lymphocytes (CTL) are a subset of T-cells that play a critical role in protecting against intracellular infections and cancer, and have the ability to identify and kill infected or transformed cells expressing non-self peptides associated with major histocompatibility (MHC) Class I molecules. Conversely, aberrant CTL activity can contribute to immune-related pathology under conditions of overwhelming infection or autoimmunity. Disease-modifying therapeutics can have unintended effects on CTL, and a growing number of therapeutics are intended to either suppress or enhance CTL or their functions. The susceptibility of CTL to unintended effects from common therapeutic modalities underscores the need for a better understanding of the impact that such therapies have on CTL function and the associated safety implications. While there are reliable ways of quantifying CTL, notably via flow cytometric analysis of specific CTL markers, it has been a greater challenge to implement fit-for-purpose methods measuring CTL function in the context of safety studies of therapeutics. This review focuses on methods for measuring CTL responses in the context of drug safety and pharmacology testing, with the goals of informing the reader about current approaches, evaluating their pros and cons, and providing perspectives on the utility of these approaches for safety evaluation.

Epidemiological Factors Associated With Caligus rogercresseyi Infection, Abundance, and Spatial Distribution in Southern Chile

Sea lice (Caligus rogercresseyi) are external parasites that affect farmed salmonids in Chile, and the scale of their sanitary and economic impact cannot be overstated. Even though space–time patterns suppose parasite aggregation, specific locations related to different infestation levels, as well as their associated factors across the geographic range involved, had not been investigated as of the writing of the present article. The understanding of the effects and factors entailed by the presence of C. rogercresseyi may be deemed a key element of Integrated Pest Management (IPM). In the present study, the multivariate spatial scan statistic was used to identify geographic areas and times of C. rogercresseyi infestation and to estimate the factors associated with such patterns. We used official C. rogercresseyi monitoring data at the farm level, with a set of 13 covariates, to provide adjustment within the analyses. The analyses were carried out for a period of 5 years (2012–2016), and they included three fish species (Salmo salar, Oncorhynchus mykiss, and Oncorhynchus kisutch) in order to assess the consistency of the identified clusters. A retrospective multinomial, spatial, and temporal scan test was implemented to identify farm clusters of either of the different categories of C. rogercresseyi infested farms: baseline, medium, and high, based on the control chemical threshold established by the health authority. The baseline represents adequate farm performance against C. rogercresseyi infestation. Then, production and environmental factors of the medium and high infestation farms were compared with the baseline using regression techniques. The results revealed a total of 26 clusters (p < 0.001), of which 12 correspond to baseline, 1 to medium, and the remaining 13 to high infestation clusters. In general, baseline clusters are detected in a latitudinal gradient on estuarine areas, with increasing relative risks to complex island water systems. There is a spatial structure in specific sites, north of Los Lagos Region and central Aysén Region, with high infestation clusters and epidemic peaks during 2013. In addition, average weight, salmon species, chemotherapeutants, latitude, temperature, salinity, and year category are factors associated with these C. rogercresseyi patterns. Recommendations for an IPM plan are provided, along with a discussion that considers the involvement of stock density thresholds by salmon species and the spatial structure of the efficacy of chemical control, both intended to avoid the advance of resistance and to minimize environmental residues.

Migratory Dendritic Cells, Group 1 Innate Lymphoid Cells, and Inflammatory Monocytes Collaborate to Recruit NK Cells to the Virus-Infected Lymph Node

Circulating natural killer (NK) cells help protect the host from lympho-hematogenous acute viral diseases by rapidly entering draining lymph nodes (dLNs) to curb virus dissemination. Here, we identify a highly choreographed mechanism underlying this process. Using footpad infection with ectromelia virus, a pathogenic DNA virus of mice, we show that TLR9/MyD88 sensing induces NKG2D ligands in virus-infected, skin-derived migratory dendritic cells (mDCs) to induce production of IFN-γ by classical NK cells and other types of group 1 innate lymphoid cells (ILCs) already in dLNs, via NKG2D. Uninfected inflammatory monocytes, also recruited to dLNs by mDCs in a TLR9/MyD88-dependent manner, respond to IFN-γ by secreting CXCL9 for optimal CXCR3-dependent recruitment of circulating NK cells. This work unveils a TLR9/MyD88-dependent mechanism whereby in dLNs, three cell types-mDCs, group 1 ILCs (mostly NK cells), and inflammatory monocytes-coordinate the recruitment of protective circulating NK cells to dLNs.

Addison's Disease Secondary to Prostatic Carcinoma. A Case Report

Adrenal cortical insufficiency secondary to destruction of the cortex by a metastatic tumor is a rare condition. Addison's disease is usually caused by an autoimmune process or by a tuberculous infection. We report a case of adrenal Insufficiency as the first clinical manifestation of a metastatic prostate carcinoma that occurred simultaneously with an active pulmonary infection by M. tuberculosis.

Cutting Edge: Protection by Antiviral Memory CD8 T Cells Requires Rapidly Produced Antigen in Large Amounts

Numerous attempts to produce antiviral vaccines by harnessing memory CD8 T cells have failed. A barrier to progress is that we do not know what makes an Ag a viable target of protective CD8 T cell memory. We found that in mice susceptible to lethal mousepox (the mouse homolog of human smallpox), a dendritic cell vaccine that induced memory CD8 T cells fully protected mice when the infecting virus produced Ag in large quantities and with rapid kinetics. Protection did not occur when the Ag was produced in low amounts, even with rapid kinetics, and protection was only partial when the Ag was produced in large quantities but with slow kinetics. Hence, the amount and timing of Ag expression appear to be key determinants of memory CD8 T cell antiviral protective immunity. These findings may have important implications for vaccine design.

Optimal design for parameter estimation in EEG problems in a 3D multilayered domain

The fundamental problem of collecting data in the ``best way'' in order to assure statistically efficient estimation of parameters is known as Optimal Experimental Design. Many inverse problems consist in selecting best parameter values of a given mathematical model based on fits to measured data. These are usually formulated as optimization problems and the accuracy of their solutions depends not only on the chosen optimization scheme but also on the given data. We consider an electromagnetic interrogation problem, specifically one arising in an electroencephalography (EEG) problem, of finding optimal number and locations for sensors for source identification in a 3D unit sphere from data on its boundary. In this effort we compare the use of the classical D-optimal criterion for observation points as opposed to that for a uniform observation mesh. We consider location and best number of sensors and report results based on statistical uncertainty analysis of the resulting estimated parameters.

Analytical evaluation of a high-throughput enzyme-linked immunosorbent assay for acrylamide determination in fried foods

The analytical performance and evaluation of a kit-based ELISA for the determination of acrylamide in fried potato and corn chip samples are described. The sample homogenate is subjected to clean-up using SPE, followed by analyte derivatization and ELISA detection. Accuracy, precision and linearity of the ELISA procedure have been validated using spiked samples. Analytical recovery ranged from 91.8% to 96.0% with coefficients of variation below 15%. Good linearity over a wide range of dilution and minimal assay drift was observed within a microtiter plate. IC50 value of the calibration curve was 110 ng/mL, with the limit of detection about 5 ng/mL and dynamic range from 10 to 1000 ng/mL. The high specificity of the ELISA was demonstrated by cross-reactivity study using 11 potential cross-reactants. A good correlation between the results obtained from the ELISA and GC-MS within the concentration range 120-1500 μg/kg was found in the chip samples (r=0.992, n=120). The data demonstrate that the evaluated and validated ELISA has a potential utility in a quick, simple and reliable acrylamide screening analysis for the medium- and large-sized food companies, as well as for residue laboratories and the food industry dealing with improving the chemical safety of foods available to the consumer.

Temperature enhanced effects of chlorine exposure on the health status of the sentinel organism Mytilus galloprovincialis

It now is widely recognised that the global temperature is rising, a phenomenon which could alter the effects of pollution on wildlife. In order to assess the role of temperature and exposure to chlorine due to cooling water discharges, a battery of metabolic, oxidative stress and histological parameters were evaluated in Mytilus galloprovincialis after 15 and 30 days at 15 °C and at two increased temperatures (+5 and +10 °C). Diverse gill pathologies such as haemolymphatic sinus dilatation, an increased number of mucocytes and granulocytes as well as a lower number of cilia were observed after 30 days exposure at higher temperatures. Protein, amino acid, triglyceride and fatty acid levels decreased when the temperature increased, as a consequence of higher energetic demand. Similarly, acetylcholinesterase, catalase and glutathione S-transferase activities showed an inhibition at higher temperatures, although gill lipid peroxidation levels remained unaffected. Our results suggest that increased temperatures induce deterioration in the health status of the mussels and in their defensive capacity against a polluted environment.

Crosstalk between the type 1 interferon and nuclear factor kappa B pathways confers resistance to a lethal virus infection

Nuclear factor kappa B (NF-κB) and type 1 interferon (T1-IFN) signaling are innate immune mechanisms activated upon viral infection. However, the role of NF-κB and its interplay with T1-IFN in antiviral immunity is poorly understood. We show that NF-κB is essential for resistance to ectromelia virus (ECTV), a mouse orthopoxvirus related to the virus causing human smallpox. Additionally, an ECTV mutant lacking an NF-κB inhibitor activates NF-κB more effectively in vivo, resulting in increased proinflammatory molecule transcription in uninfected cells and organs and decreased viral replication. Unexpectedly, NF-κB activation compensates for genetic defects in the T1-IFN pathway, such as a deficiency in the IRF7 transcription factor, resulting in virus control. Thus, overlap between the T1-IFN and NF-κB pathways allows the host to overcome genetic or pathogen-induced deficiencies in T1-IFN and survive an otherwise lethal poxvirus infection. These findings may also explain why some pathogens target both pathways to cause disease.

Memory CD8⁺ T cells can outsource IFN-γ production but not cytolytic killing for antiviral protection

Immunization with vaccinia virus (VACV), the virus comprising the smallpox vaccine, induces memory CD8(+) T cells that protect from subsequent infections with smallpox in humans or the related ectromelia virus (ECTV) in mice. Memory CD8(+) T cells largely mediate these effects by expanding into secondary effectors that secrete the antiviral cytokine interferon-γ (IFN-γ) and induce cytolysis via releasing factors such as perforin, which permeabilizes target cells. We show that protection from ECTV infection after VACV immunization depends on the initial memory cell frequency and ability of expanded secondary effectors to kill infected targets in a perforin-dependent manner. Although IFN-γ is essential for antiviral protection, it can be produced by either secondary effectors or concomitant primary effector CD8(+) T cells recruited to the response. Thus, during lethal virus challenge, memory CD8(+) T cells are required for cytolytic killing of infected cells, but primary effectors can play important roles by producing IFN-γ.

Comparative effect of simulated solar light, UV, UV/H2O2 and photo-Fenton treatment (UV-Vis/H2O2/Fe2+,3+) in the Escherichia coli inactivation in artificial seawater

Innovative disinfection technologies are being studied for seawater, seeking a viable alternative to chlorination. This study proposes the use of H2O2/UV254 and photo-Fenton as disinfection treatment in seawater. The irradiations were carried out using a sunlight simulator (Suntest) and a cylindrical UV reactor. The efficiency of the treatment was compared for Milli-Q water, Leman Lake water and artificial seawater. The presence of bicarbonates and organic matter was investigated in order to evaluate possible effects on the photo-Fenton disinfection treatment. The photo-Fenton treatment, employing 1 mg L(-1) Fe(2+) and 10 mg L(-1) of H2O2, led to the fastest bacterial inactivation kinetics. Using H2O2/UV254 high disinfection rates were obtained similar to those obtained with photo-Fenton under UV254 light. In Milli-Q water, the rate of inactivation for Escherichia coli was higher than in Leman Lake water and seawater due to the lack of inorganic ions affecting negatively bacteria inactivation. The presence of bicarbonate showed scavenging of the OH(•) radicals generated in the treatment of photo-Fenton and H2O2/UV254. Despite the negative effect of inorganic ions, especially HCO3(-), the disinfection treatments with AOPs in lake water and seawater improved significantly the disinfection compared to light alone (simulated sunlight and UV254). In the treatment of photo-Fenton with simulated sunlight, dissolved organic matter had a beneficial effect by increasing the rate of inactivation. This is associated with the formation of Fe(3+)-organo photosensitive complexes leading to the formation of ROS able to inactivate bacteria. This effect was not observed in the photo-Fenton with UV254. Growth of E. coli surviving in seawater was observed 24 and 48 h after treatment with UV light. However, growth of surviving bacteria was not detected after photo-Fenton with UV254 and H2O2/UV254 treatments. This study suggests H2O2/UV254 and photo-Fenton treatments for the disinfection of seawater, in spite its high concentration of salts.

Antibody inhibition of a viral type 1 interferon decoy receptor cures a viral disease by restoring interferon signaling in the liver

Type 1 interferons (T1-IFNs) play a major role in antiviral defense, but when or how they protect during infections that spread through the lympho-hematogenous route is not known. Orthopoxviruses, including those that produce smallpox and mousepox, spread lympho-hematogenously. They also encode a decoy receptor for T1-IFN, the T1-IFN binding protein (T1-IFNbp), which is essential for virulence. We demonstrate that during mousepox, T1-IFNs protect the liver locally rather than systemically, and that the T1-IFNbp attaches to uninfected cells surrounding infected foci in the liver and the spleen to impair their ability to receive T1-IFN signaling, thus facilitating virus spread. Remarkably, this process can be reversed and mousepox cured late in infection by treating with antibodies that block the biological function of the T1-IFNbp. Thus, our findings provide insights on how T1-IFNs function and are evaded during a viral infection in vivo, and unveil a novel mechanism for antibody-mediated antiviral therapy.

Type 1 interferons are molecules important in the defense against viruses. Orthopoxviruses encode a Type 1 interferon binding protein that acts as a decoy for the Type 1 interferon receptor. Here we show that during infection with the Orthopoxvirus ectromelia virus, the agent of mousepox, Type 1 interferons protect the liver locally rather than systemically. We also show that the Type 1 interferon binding protein of ectromelia virus attaches to uninfected cells surrounding infected foci in the liver to impair their ability to receive Type 1 interferon signaling and facilitate virus spread and disease progression. We also show that this process can be reversed and mousepox cured late in infection by treating mice with antibodies that block the biological function of the Type 1 interferon binding protein. Because the Type 1 interferon binding proteins of different Orthopoxviruses are very well conserved, the antibodies also block the biological function of the Type 1 interferon binding proteins from variola virus (the virus of smallpox) and monkeypoxvirus. Thus, our findings provide insights on how Type 1 interferons function and are evaded during a viral infection in vivo, and unveil a novel mechanism for antibody-mediated antiviral therapy.

Ectromelia NF-κβ inhibitor 002 is essential for virus pathogenesis (154.4)

Ectromelia virus is an orthopoxvirus and the causative agent of mousepox in mice. The virus codifies several proteins to control the host response. One of them is the NF-κβ inhibitor, ECTV 002 which has orthologs in other poxviruses including cowpox, monkeypox and variola viruses. We generated an ectromelia virus that lacks this gene (ECTV Δ002) and its correspondent revertant virus. Both viruses grew normally in vitro; however, when used to infected BALB/C mice in the footpad, only the WT and revertant viruses killed the mice. When using different doses, the LD50s were lower than 1pfu for the WT and revertant viruses but higher than 105 for the ECTV Δ002 indicating an attenuation of at least 5 orders of magnitude. We then analyzed the virus spread by measuring virus titers in different organs. The virus load in the draining lymph node was lower in mice infected with the ECTV Δ002 than with the revertant virus and consequently, the virus titer in peripheral organs like spleen or liver was lower as well. When we compared the immune responses in the draining lymph nodes by flow cytometry, we did not find significant differences between ECTV Δ002 and WT viruses. However, 7 dpi, the mice infected with ECTV Δ002 had elevated numbers of NK, CD8 and CD4 cells in their spleens as compared to mice infected with revertant virus. Altogether our results show that ECTV 002 is essential for ECTV pathogenesis and that the control of the infection occurs early in the draining lymph node.

Memory CD8+ T cells deficient in IFN-γ protect from a lethal viral disease (105.3)

Ectromelia virus (ECTV), the causative agent of mousepox, is a lethal mouse pathogen of the Orthopoxvirus genus, which also includes variola virus. C57Bl/6 (B6) mice are resistant to ECTV infection while mice such as DBA2/J are susceptible. B6.D2-D6 mice, a B6 congenic strain with the NK complex from DBA2/J are sensitive to ECTV and can be protected by adoptive transfer of memory CD8+ T cells (MTCD8+) from convalescent mice. To ascertain the role of IFNγ in MTCD8+ mediated protection, we transferred MTCD8+ from IFNγ-/- mice (Mγ-/-) into B6.D2-D6 mice and challenged them with ECTV. All naïve CD8+ (NB6) recipients died and all recipients of memory B6 CD8+ (MB6) or Mγ-/- recipients survived. Seven dpi, MB6 and Mγ-/- recipients had significantly less liver damage and virus titers in the spleen and liver than NB6 recipients. This demonstrates that MTCD8+ do not have to produce IFNγ to protect from a viral disease. Of interest, we also found that donor virus-specific cells promoted an endogenous virus-specific TCD8+ response in the spleens and livers of recipients. Next we determined if IFNγ was necessary when MTCD8+ cells were present by transferring MB6 or Mγ-/- CD8+ into IFNγ-/- mice. All NB6 and Mγ-/- recipients succumbed to mousepox while all recipients of MB6 recipients survived. Thus, IFNγ is required for resistance to mousepox but can be produced in sufficient quantities for protection by MTCD8+ or other non-memory cells, probably NK cells or primary T cell effectors.

Sublethal responses of the common mussel (Mytilus galloprovincialis) exposed to sodium hypochlorite and Mexel432 used as antifoulants

The sublethal effects of two antifoulants currently used in power plant cooling systems were assessed in the common mussel Mytilus galloprovincialis. The concentrations of sodium hypochlorite (NaClO) and an alkyl amine surfactant (Mexel432) assayed, were within the range of those currently discharged by power plants into receiving waters. Enzymatic activities and oxidative stress responses were measured in digestive gland and gill of mussels after 1, 3, 7 and 14 days of exposure, as well as histopathology in gill tissue. Both antifoulants caused a pathological response in gills and the activities of the enzymes glutathione S-transferase, catalase, acetylcholinesterase and the lipid peroxidation levels were also affected. Exposure to NaClO caused a greater toxicological response than Mexel432. In both treatments, gills appeared to be the most affected tissue, although Mexel432 also significantly affected digestive gland parameters.

Sublethal effects of the organic antifoulant Mexel(R)432 on osmoregulation and xenobiotic detoxification in the flatfish Solea senegalensis

Mexel(R)432 is an anionic surfactant used as biocide in the cooling water system of power plants for biofouling reduction. Refrigeration waters from power plants do not usually follow, prior to their discharge to sea, any treatment aimed to eliminate biocides and this can have negative consequences on the aquatic fauna nearby. The effects of different concentrations of the antifoulant Mexel(R)432 (0.5, 1 and 2mgL(-1)) on osmoregulation (osmolality and Na(+)/K(+)-ATPase activity) and stress parameters (cortisol, glucose, and lactate) were assessed in juveniles of the flatfish Solea senegalensis. Gill histopathology and alterations due to oxidative stress (increased lipid peroxidation, LPO, levels) at branchial and hepatic levels were also considered. Other parameters tested were the antioxidant enzymes (catalase, CAT; glutathione peroxidase, GPX; and glutathione reductase, GR), xenobiotic metabolism defenses involved in detoxification (carboxylesterase, CbE; 7-ethoxyresorufin O-deethylase, EROD; and glutathione S-transferase, GST) and the neurotransmitter acetylcholinesterase (AChE) activity. Significant variations in osmoregulatory parameters, histological lesions and decreased branchial Na(+)/K(+)-ATPase activity were observed in exposed fish. Other gill biomarkers presented little or no significant variations in relation to controls. In contrast, hepatic parameters, such as CAT activity, were inhibited while EROD activity was initially elevated but after longer exposures it recovered basal values. These results suggested that under our experimental protocol exists toxic associated to Mexel(R)432 exposures.

Biomarker responses in Solea senegalensis exposed to sodium hypochlorite used as antifouling

The time-course stress responses (0, 1, 2, and 7 d) was assessed in plasmatic, branchial and renal parameters of juveniles Solea senegalensis exposed to different concentrations of the antifouling sodium hypochlorite (0.1, 0.2, and 0.5mgL(-1)). These stress responses were only assessed for the total length of exposure (7d) at the lowest NaClO concentration due to the high toxicity of this chemical. In addition, the xenobiotic metabolism responses were evaluated by means of enzymatic activities of ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPX), catalase (CAT), and carboxylesterase (CbE) in liver; as well as GST, GPX, CAT and acetylcholinesterase (AChE) in gill. Oxidative stress damage due to sodium hypochlorite exposure was measured by lipid peroxidation levels in liver and gill. Concentrations of 0.2 and 0.5mgL(-1) produced lethal effects after 1d and 2h of exposure, respectively. After 1d of exposure to sublethal concentration of sodium hypochlorite (0.1mgL(-1)) osmoregulatory (osmolality and chloride) and stress (cortisol, glucose and lactate) plasmatic parameters were enhanced to respect at control fish. However after 3 or 7d these parameters returned to control values. No effects were observed on plasma protein and triglyceride levels or on gill and kidney Na(+)/K(+)-ATPase activities. Diverse gill pathologies such as hypertrophy, lamellar fusion and an increase in goblet cell number and size were observed after 7d of exposure. Most biochemical parameters related to xenobiotic metabolism and oxidative stress were also significantly affected which suggests that seawater affected by sodium hypochlorite discharges from power plants, is able to alter the fish xenobiotic metabolism and generate oxidative stress.

Molecular characterization of spontaneous mesenchymal stem cell transformation

Background

We previously reported the in vitro spontaneous transformation of human mesenchymal stem cells (MSC) generating a population with tumorigenic potential, that we termed transformed mesenchymal cells (TMC).

Methodology/Principal Findings

Here we have characterized the molecular changes associated with TMC generation. Using microarrays techniques we identified a set of altered pathways and a greater number of downregulated than upregulated genes during MSC transformation, in part due to the expression of many untranslated RNAs in MSC. Microarray results were validated by qRT-PCR and protein detection.

Conclusions/Significance

In our model, the transformation process takes place through two sequential steps; first MSC bypass senescence by upregulating c-myc and repressing p16 levels. The cells then bypass cell crisis with acquisition of telomerase activity, Ink4a/Arf locus deletion and Rb hyperphosphorylation. Other transformation-associated changes include modulation of mitochondrial metabolism, DNA damage-repair proteins and cell cycle regulators. In this work we have characterized the molecular mechanisms implicated in TMC generation and we propose a two-stage model by which a human MSC becomes a tumor cell.

Pattern formation driven by an acid-base neutralization reaction in aqueous media in a gravitational field

We report the hydrodynamic instabilities found in a simple exothermic neutralization reaction. Although the heavier aqueous NaOH solution was put below the lighter layer of aqueous HCl solution, fingering at the interface in a Hele-Shaw cell was observed. The reaction front, which propagates downward, becomes buoyantly unstable in the gravity field. The mixing zone length and wave number depend on the reactant concentrations. The mixing zone length increases and the wave number decreases when the reactant concentrations decrease.

Human mesenchymal stem cell transformation is associated with a mesenchymal-epithelial transition

Carcinomas are widely thought to derive from epithelial cells with malignant progression often associated with an epithelial-mesenchymal transition (EMT). We have characterized tumors generated by spontaneously transformed human mesenchymal cells (TMC) previously obtained in our laboratory. Immunohistopathological analyses identified these tumors as poorly differentiated carcinomas, suggesting that a mesenchymal-epithelial transition (MET) was involved in the generation of TMC. This was corroborated by microarray and protein expression analysis that showed that almost all mesenchymal-related genes were severely repressed in these TMC. Interestingly, TMC also expressed embryonic antigens and were able to integrate into developing blastocysts with no signs of tumor formation, suggesting a dedifferentiation process was associated with the mesenchymal stem cell (MSC) transformation. These findings support the hypothesis that some carcinomas are derived from mesenchymal rather than from epithelial precursors.

Refinement of intrathymic injection in mice

Direct intrathymic injection is a common procedure used in several types of experimental protocols in the mouse. Currently available approaches involve major surgical procedures that expose the thoracic cavity, resulting in an increased risk of poor recovery and postsurgical complications. The authors sought to refine this surgery to reduce animal pain and distress without compromising overall efficiency of the technique. Using a minimally invasive method that does not expose the thoracic cavity, the authors gave accurately placed intrathymic injections, as confirmed by analyses with a reporter dye. They describe this new approach for intrathymic injection in mice that reduces complications associated with lengthy periods of anesthesia and thoracic cavity exposure.

Spontaneous human adult stem cell transformation

Human adult stem cells are being evaluated widely for various therapeutic approaches. Several recent clinical trials have reported their safety, showing them to be highly resistant to transformation. The clear similarities between stem cell and cancer stem cell genetic programs are nonetheless the basis of a recent proposal that some cancer stem cells could derive from human adult stem cells. Here we show that although they can be managed safely during the standard ex vivo expansion period (6-8 weeks), human mesenchymal stem cells can undergo spontaneous transformation following long-term in vitro culture (4-5 months). This is the first report of spontaneous transformation of human adult stem cells, supporting the hypothesis of cancer stem cell origin. Our findings indicate the importance of biosafety studies of mesenchymal stem cell biology to efficiently exploit their full clinical therapeutic potential.

Dedifferentiated adult articular chondrocytes: a population of human multipotent primitive cells

OBJECTIVE

To test the hypothesis that dedifferentiated adult human cartilage chondrocytes (HAC) are a true multipotent primitive population.

METHODS

Studies to characterize dedifferentiated HAC included cell cycle and quiescence analysis, cell fusion, flow-FISH telomere length assays, and ABC transporter analysis. Dedifferentiated HAC were characterized by flow cytometry, in parallel with bone marrow mesenchymal stem cells (MSC) and processed lipoaspirate (PLA) cells. The in vitro differentiation potential of dedifferentiated HAC was studied by cell culture under several inducing conditions, in multiclonal and clonal cell populations.

RESULTS

Long-term HAC cultures were chromosomically stable and maintained cell cycle dynamics while showing telomere shortening. The phenotype of dedifferentiated HAC was quite similar to that of human bone marrow MSC. In addition, this population expressed human embryonic stem cell markers. Multiclonal populations of dedifferentiated HAC differentiated to chondrogenic, osteogenic, adipogenic, myogenic, and neurogenic lineages. Following VEGF induction, dedifferentiated HAC expressed characteristics of endothelial cells, including AcLDL uptake. A total of 53 clonal populations of dedifferentiated HAC were efficiently expanded; 17 were able to differentiate to chondrogenic, osteogenic, and adipogenic lineages. No correlation was observed between telomere length or quiescent population and differentiation potential in the clones assayed.

CONCLUSION

Dedifferentiated HAC should be considered a human multipotent primitive population.

Polyprotein processing protease of African swine fever virus: purification and biochemical characterization

The purified recombinant African swine fever virus polyprotein processing protease cleaves the two GG-X sites in polyprotein pp62 with the same efficiency. Cleavage at the site that is first recognized in vivo is not a requisite for cleavage at the second site, suggesting the existence of mechanisms that control the ordered processing of the polyprotein during infection.

Comparative study of several lymphocyte functions in two strains of mice with different models of endotoxic shock

Previously, the changes in phagocyte functions such as adherence, chemotaxis or TNFalpha production were found to be associated with oxidative stress in endotoxin-induced septic shock. However, in this type of oxidative stress the lymphocyte involvement has rarely been studied. In the present report, we analyzed the above functions in peritoneal lymphocytes from male and female BALB/c mice with a lethal endotoxic shock caused by intraperitoneal injection of E. coli lipopolysaccharide (LPS) (100 mg/kg), male and female Swiss mice with lethal endotoxic shock caused by intraperitoneal injection of LPS (150 and 250 mg/kg, respectively) or non-lethal endotoxic shock (100 mg/kg). In peritoneal lymphocytes obtained at 0, 2, 4, 12 or 24 h after LPS injection, the first two functions of these cells in the immune response, i.e. adherence to tissues and directed migration (chemotaxis), were studied. At 0, 0.5, 1, 1.5, 2, 4, 12 and 24 h after LPS injection, TNFalpha released by lymphocytes was also analyzed. The results show that endotoxic shock increases the adherence and TNFalpha release, and decreases the chemotaxis of peritoneal lymphocytes. These changes were more significant in mice with lethal than with non-lethal endotoxic shock, a fact that confirms the important role of lymphocytes during endotoxic shock.

Enzyme-mediated solvent extraction of carotenoids from marigold flower (Tagetes erecta)

Marigold flowers are the most important source of carotenoids for application in the food industry. However, the extraction gives almost 50% losses of the carotenoids depending on conditions for silaging, drying, and solvent extraction. In the past decades, macerating enzymes have been successfully applied to improve the extraction yield of valued compounds from natural products. In this work, an alternative extraction process for carotenoids is proposed, consisting of a simultaneous enzymatic treatment and solvent extraction. The proposed process employs milled fresh flowers directly as raw material, eliminating the inefficient silage and drying operations as well as the generation of hard to deal with aqueous effluents present in traditional processes. The process developed was tested at the 80 L scale, where under optimal conditions a carotenoid recovery yield of 97% was obtained.

31Phosphorus magnetic resonance spectroscopy in the assessment of head and neck tumors

PURPOSE

31Phosphorus magnetic resonance spectroscopy (31P-MRS) provides biochemical information in a noninvasive way. The aim of this work was: (a) to characterize the 31P spectrum of advanced head and neck tumors, and (b) to evaluate the spectral changes after treatment and to correlate them with the pathologic response.

METHODS AND MATERIALS

A total of 20 patients diagnosed with advanced head and neck tumors and 7 healthy controls participated in the study. The tumor mass and its contralateral side were studied by means of 31P-MRS before and after treatment. Neck muscles of a control group were also studied.

RESULTS

Tumors presented ratios of phosphomonoesters (PME), phosphodiesters (PDE), and inorganic phosphate (Pi) with respect to the adenosine triphosphate (ATP), significantly higher and a PCr (phosphocreatine)/ATP ratio lower than the neck muscle of volunteers or the contralateral side. The PDE/ATP and PME/ATP ratio values obtained before therapy were similar, independent of the later response to treatment. However, when there was a complete response, the ratios measured after treatment were decreased.

CONCLUSION

These results show the existence of significant differences between the 31phosphorus spectrum of tumors and neck muscle, but also between the tumors and their contralateral sides. Moreover, 31P-MRS is able to detect metabolic changes after a complete response. These results suggest that 31P-MRS would be useful in the evaluation of the clinical response of head and neck tumors.

Cisplatin and vinorelbine followed by radiotherapy in the treatment of stage III-B non-small-cell lung cancer patients

Combined chemotherapy/radiotherapy treatments appear to yield better results in locally advanced non-small-cell lung cancer (NSCLC) than radiotherapy alone. The optimal induction chemotherapy regimen remains to be established. In the present study, chemotherapy with cisplatin and vinorelbine was used prior to radical radiotherapy in Stage III-B NSCLC. Thirty-three patients were entered prospectively into a Phase II study. Treatment consisted of three cycles of chemotherapy with cisplatin 100 mg/m2 on day 1 and vinorelbine 30 mg/m2 on days 1 and 8, followed by thoracic radiotherapy (60 Gy). Twenty-two percent of the 33 patients had grade 3-4 leukopenia, and there were six episodes (in 4 patients) of neutropenia-associated fever. Gastrointestinal toxicity was generally moderate. Peripheral neuropathy was present in 42% of the patients, although in most of them it was slight. The main radiotherapy toxicity was esophagitis grade I-II. Evaluation of response after the third chemotherapy course showed an objective response in 16 patients (48%), whereas in three patients (9%) the disease progressed during therapy. The median survival of the entire group was 13 months. Cisplatin plus vinorelbine followed by radiotherapy is an effective schedule for patients with locally advanced non-small-cell lung cancer.

Fluorouracil and high-dose leucovorin with radiotherapy as adjuvant therapy for rectal cancer. Results of a phase II study

The purpose of this phase II study was to evaluate the efficacy and toxicity of fluorouracil and high-dose leucovorin (5-FU/LV) with pelvic irradiation as adjuvant therapy for patients with macroscopical resected rectal or recto-sigmoid cancer. Following surgery for stages II-III primary (52) or recurrent rectal cancer (4), 56 patients received 8 cycles of 5-FU/LV and pelvic irradiation. 5-FU doses were 200 mgr/m2 for cycles 2-3 and 300 mgr/m2 for cycles 1 and 4-8. LV doses remained fixed at 200 mgr/m2. Pelvic radiation was started in the third week, between the first and second cycle. The total dose was 50.4 Gy. No severe complications had been recorded. The incidence of grade 3 diarrhea was 19%. Three patients presented leukopenia grade 3 (5%). In 44 patients (78%) the planned treatment could be administered. The median follow-up was 40 months (range 22-66). Seven patients had a local relapse (13%) and 6 developed distant metastasis (10%). The 3-year disease-free survival was 72% and the overall survival was 76%. These preliminary results show that combined post-operative 5-FU/LV and pelvic radiotherapy are well tolerated and present a reasonable local control and survival rates. This adjuvant treatment should be evaluated in randomized trials.

[C-erbB-2 protein in ovarian epithelial cancer: correlation between expression in tumor tissue and blood levels]

BACKGROUND

Among 20 to 30% of the patients with ovarian cancer present overexpression of the c-erbB protein in the tumor tissue although its clinical significance has not been clearly established. In patients with a disseminated neoplasm and overexpression of c-erbB an increase in the extracellular portion of this protein may be detected in serum. The aim of this study was to determine the c-erbB protein in serum and in tumoral tissue in patients diagnosed with ovarian epithelial carcinoma.

METHODS

The serum concentration of the c-erbB protein was quantified by ELISA techniques in 60 blood donor women (control group) and in 99 patients with ovarian cancer. Likewise, the expression of the c-erbB protein was determined in tumoral tissue by immunohistochemical techniques in the 99 patients with ovarian cancer. The correlation between overexpression and elevated serum values was analyzed.

RESULTS

The mean c-erbB values obtained in the serum of the control group was 10.9 U/ml (SD: 2.8) with a range of 1.5-17.0. Serum determination was carried out in absence of the tumor in 49 patients being positive in 2 cases. In 7 patients the determination was performed in the presence of peritoneal implants of a diameter of less than 2 cm with none being positive. Serum determination was carried out in 43 patients in the presence of implants greater than 2 cm and 14 (32.5%) were positive. A further 153 determinations were performed during follow up of the 99 patients, 62 in tumor absence (3.2% positive), 2 in the presence of a tumor of less than 2 cm (none positive) and 89 in the presence of a tumor greater than 2 cm (34.8% positive). A correlation was found between elevated c-erbB serum values in the presence of a disseminated tumors and overexpression of tumoral tissue (p: 0.0011).

CONCLUSIONS

A third of the patients with ovarian cancer and peritoneal implants of a diameter greater than 2 cm present elevated serum levels of the c-erbB.2 protein. A correlation was found between serum c-erbB positivity and overexpression of the protein in tumoral tissue.

Overexpression of c-erbB-2 in epithelial ovarian cancer. Prognostic value and relationship with response to chemotherapy

BACKGROUND

Overexpression of the c-erbB-2 protein has been reported in tumors from approximately 25% of patients with epithelial ovarian cancer. However, its clinical significance has not been well established.

METHODS

Overexpression of the c-erbB-2 protein was studied by immunohistochemistry in paraffin-embedded tumor tissue from 106 patients with ovarian cancer.

RESULTS

Tumors from 23 patients (21.7%) had c-erbB-2 overexpression. The percentage of tumors with overexpression was higher in those with Stages III/IV disease (29.2%) compared with those with Stages I/II disease (5.9%) (P = 0.057), in patients with residual tumor greater than 2 cm after initial surgery (37.2%) compared with those with tumor less than 2 cm (9.5%) (P = 0.01), and in patients who failed to respond to chemotherapy with carboplatin and cyclophosphamide (75%) compared with those who responded (18.6%) (P = 0.0043). No correlation was found between c-erbB-2 expression with age, the degree of differentiation, or the histologic subtype. Median survival of the 23 patients with protein overexpression was 62 weeks, whereas 75% of the 83 patients without overexpression were alive at 123 weeks (P = 0.0000). Of the patients with advanced stage disease (III/IV), survival was also lower in those presenting with overexpression (60 weeks) compared with those without expression (75% alive at 93 weeks) (P = 0.0000). Multivariate analysis of possible prognostic factors showed that c-erbB-2 overexpression and residual tumor greater than 2 cm resulted in a worsening of survival rates.

CONCLUSION

c-erbB-2 overexpression in tumors from patients with ovarian cancer resulted in a poorer prognosis than for patients whose tumors did not have overexpression.

A comparative study of aerobic capacity and fitness in three different horse breeds (Andalusian, Arabian and Anglo-Arabian)

Aerobic capacity and fitness was studied in three different horse breeds (Andalusian, Arabian and Anglo-Arabian) using a four-level exercise test of gradually increasing intensity (15, 20, 25 and 30 km/h). The lactate concentration at the first three exercise levels was significantly lower for Arabian and Anglo-Arabian horses relative to Andalusian horses, but similar for the three breeds at the last level. Arabian and Anglo-Arabian horses reached a higher rate than Andalusian horses at plasma lactate concentration of 2 mmol/l (VLA2) and 4 mmol/l (VLA4). Andalusian horses exhibited a significantly lower heart rate at rest than the other two breeds, but the differences virtually disappeared at 15 km/h. At 20 km/h, Andalusian horses reached a higher heart rate than Arabian and Anglo-Arabian horses; at 25 km/h, however, their heart rate only exceeded that of Anglo-Arabian horses. Finally, no significant differences between breeds were observed at 30 km/h. No differences between breeds as regards heart rate were found if this was expressed as a function of lactate plasma concentrations of 2 mmol/l (HRLA2) and 4 mmol/l (HRLA4). At a heart rate of 150 (VHR150) and 200 beta/min (VHR200), Andalusian horses achieved the lowest speeds.

Long-term survival in advanced ovarian cancer after cytoreduction and chemotherapy treatment

Ninety-one patients with untreated epithelial ovarian cancer, stages III and IV, were treated according to a therapeutic protocol including cytoreductive surgery whenever possible, chemotherapy with CAP (cyclophosphamide, doxorubicin, and cisplatin) and second-look laparotomy for those patients achieving a clinical remission. Optimal cytoreductive surgery (residual tumor < 2 cm) was not performed in 66 patients (72.5%). A negative second-look laparotomy demonstrated a pathological complete remission in 26 patients (28.5%). After a median follow-up of 80 months, the disease-free survival is 19.7% (18 of 91 patients). Median survival was greater in optimal cytoreductive surgery patients (47 months) than in the rest of the patients (22 months) (P = 0.0000). Survival was also better in pathological complete remission patients (46 months) than in partial remission (PR) or no response patients (22 months) (P = 0.0001). Optimal secondary cytoreductive surgery was possible in 11 patients in PR after chemotherapy. Survival in this group was similar to that of pathological complete remission cases. Currently, 53% of patients with initial residual tumor < 2 cm and complete response at second-look remain free of disease. In a multivariate analysis, residual tumor > 2 cm and stage IV disease were the most significant prognostic factors. The same analysis indicates that response to chemotherapy at second laparotomy is not an independent prognostic factor. In conclusion, our study indicates that the two most important prognostic factors in advanced ovarian carcinoma are the extent of the initial surgery and stage.