PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (101)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
more »
3.  Histone deacetylase inhibitors promote glioma cell death by G2 checkpoint abrogation leading to mitotic catastrophe 
Cell Death & Disease  2014;5(10):e1435-.
Glioblastoma multiforme is resistant to conventional anti-tumoral treatments due to its infiltrative nature and capability of relapse; therefore, research efforts focus on characterizing gliomagenesis and identifying molecular targets useful on therapy. New therapeutic strategies are being tested in patients, such as Histone deacetylase inhibitors (HDACi) either alone or in combination with other therapies. Here two HDACi included in clinical trials have been tested, suberanilohydroxamic acid (SAHA) and valproic acid (VPA), to characterize their effects on glioma cell growth in vitro and to determine the molecular changes that promote cancer cell death. We found that both HDACi reduce glioma cell viability, proliferation and clonogenicity. They have multiple effects, such as inducing the production of reactive oxygen species (ROS) and activating the mitochondrial apoptotic pathway, nevertheless cell death is not prevented by the pan-caspase inhibitor Q-VD-OPh. Importantly, we found that HDACi alter cell cycle progression by decreasing the expression of G2 checkpoint kinases Wee1 and checkpoint kinase 1 (Chk1). In addition, HDACi reduce the expression of proteins involved in DNA repair (Rad51), mitotic spindle formation (TPX2) and chromosome segregation (Survivin) in glioma cells and in human glioblastoma multiforme primary cultures. Therefore, HDACi treatment causes glioma cell entry into mitosis before DNA damage could be repaired and to the formation of an aberrant mitotic spindle that results in glioma cell death through mitotic catastrophe-induced apoptosis.
doi:10.1038/cddis.2014.412
PMCID: PMC4237242  PMID: 25275596
4.  Land Snails as a Diet Diversification Proxy during the Early Upper Palaeolithic in Europe 
PLoS ONE  2014;9(8):e104898.
Despite the ubiquity of terrestrial gastropods in the Late Pleistocene and Holocene archaeological record, it is still unknown when and how this type of invertebrate resource was incorporated into human diets. In this paper, we report the oldest evidence of land snail exploitation as a food resource in Europe dated to 31.3-26.9 ka yr cal BP from the recently discovered site of Cova de la Barriada (eastern Iberian Peninsula). Mono-specific accumulations of large Iberus alonensis land snails (Ferussac 1821) were found in three different archaeological levels in association with combustion structures, along with lithic and faunal assemblages. Using a new analytical protocol based on taphonomic, microX-Ray Diffractometer (DXR) and biometric analyses, we investigated the patterns of selection, consumption and accumulation of land snails at the site. The results display a strong mono-specific gathering of adult individuals, most of them older than 55 weeks, which were roasted in ambers of pine and juniper under 375°C. This case study uncovers new patterns of invertebrate exploitation during the Gravettian in southwestern Europe without known precedents in the Middle Palaeolithic nor the Aurignacian. In the Mediterranean context, such an early occurrence contrasts with the neighbouring areas of Morocco, France, Italy and the Balkans, where the systematic nutritional use of land snails appears approximately 10,000 years later during the Iberomaurisian and the Late Epigravettian. The appearance of this new subsistence activity in the eastern and southern regions of Spain was coeval to other demographically driven transformations in the archaeological record, suggesting different chronological patterns of resource intensification and diet broadening along the Upper Palaeolithic in the Mediterranean basin.
doi:10.1371/journal.pone.0104898
PMCID: PMC4139308  PMID: 25141047
5.  Human XCR1+ Dendritic Cells Derived In Vitro from CD34+ Progenitors Closely Resemble Blood Dendritic Cells, Including Their Adjuvant Responsiveness, Contrary to Monocyte-Derived Dendritic Cells 
Human monocyte-derived dendritic cell (MoDC) have been used in the clinic with moderately encouraging results. Mouse XCR1+ DC excel at cross-presentation, can be targeted in vivo to induce protective immunity, and share characteristics with XCR1+ human DC. Assessment of the immunoactivation potential of XCR1+ human DC is hindered by their paucity in vivo and by their lack of a well-defined in vitro counterpart. We report in this study a protocol generating both XCR1+ and XCR1− human DC in CD34+ progenitor cultures (CD34-DC). Gene expression profiling, phenotypic characterization, and functional studies demonstrated that XCR1− CD34-DC are similar to canonical MoDC, whereas XCR1+ CD34-DC resemble XCR1+ blood DC (bDC). XCR1+ DC were strongly activated by polyinosinic-polycytidylic acid but not LPS, and conversely for MoDC. XCR1+ DC and MoDC expressed strikingly different patterns of molecules involved in inflammation and in cross-talk with NK or T cells. XCR1+ CD34-DC but not MoDC efficiently cross-presented a cell-associated Ag upon stimulation by polyinosinic-polycytidylic acid or R848, likewise to what was reported for XCR1+ bDC. Hence, it is feasible to generate high numbers of bona fide XCR1+ human DC in vitro as a model to decipher the functions of XCR1+ bDC and as a potential source of XCR1+ DC for clinical use.
doi:10.4049/jimmunol.1401243
PMCID: PMC4120898  PMID: 25009205
6.  Protective effect of trehalose-loaded liposomes against UVB-induced photodamage in human keratinocytes 
Biomedical Reports  2014;2(5):755-759.
Trehalose, a naturally occurring non-reducing disaccharide, is known to act as a major protein stabilizer that can reduce ultraviolet B (UVB)-induced corneal damage when topically applied to the eye. However, due to the low skin permeability of trehalose, which makes the development of topical formulations difficult, its use as a skin photoprotective agent has been limited. Previous findings demonstrated that liposomes may significantly improve the intracellular delivery of trehalose. Therefore, the present study aimed to assess the protective effects of trehalose-loaded liposomes against UVB-induced photodamage using the immortalized human keratinocyte cell line, HaCaT. The effects were also compared to those of the common skin photoprotective compounds, including L-carnosine, L-(+)-ergothioneine, L-ascorbic acid and DL-α-tocopherol. The levels of cyclobutane pyrimidine dimers, 8-hydroxy-2′-deoxyguanosine and protein carbonylation in HaCaT cells were used as biological markers of UVB-induced damage. Compared to other compounds, trehalose-loaded liposomes showed the highest efficacy in reducing the levels of the three markers following UVB irradiation of HaCaT cells (all P<0.001 when compared to each of the four other photoprotective compounds). Therefore, these findings indicate that there may be a clinical application for trehalose-loaded liposomes, and further studies should be performed to assess the potential usefulness in skin photoprotection and the prevention of non-melanoma skin cancer.
doi:10.3892/br.2014.310
PMCID: PMC4106593  PMID: 25054023
ultraviolet radiation; keratinocytes; trehalose; cyclobutane pyrimidine dimers; 8-hydroxy-2′-deoxyguanosine; protein carbonylation
7.  Physical activity - an important preanalytical variable 
Biochemia Medica  2014;24(1):68-79.
The concentration of several biochemical and hematological biomarkers is strongly influenced by a number of preanalytical variables. Several lines of evidence attest that short, middle, and long-term exercise, as well as the relative intensity of physical effort (from mild to strenuous), may influence a broad array of laboratory variables. The amount of extracellular release and clearance from blood of most of these biomarkers is markedly influenced by the biological characteristics of the molecule(s), level of training, type, intensity and duration of exercise, and time of recovery after training. It is hence noteworthy that test results that fall outside the conventional reference ranges in athletes not only may reflect the presence of a given disease, but may frequently mirror an adaptation to regular training or changes that have occurred during and/or following strenuous exercise, and which should be clearly acknowledged to prevent misinterpretation of laboratory data. The aim of this narrative review is to provide an update about the most significant changes of some biochemical and hematological biomarkers in response to physical exercise, for appropriate interpretation of these changes in the context of physically active subjects.
doi:10.11613/BM.2014.009
PMCID: PMC3936967  PMID: 24627716
biomarkers; training; plasma volume; metabolism; cellular damage
8.  New Molecular Targets and Lifestyle Interventions to Delay Aging Sarcopenia 
doi:10.3389/fnagi.2014.00156
PMCID: PMC4078253  PMID: 25071565
muscle atrophy; senescence factors; signaling pathways; frailty; pharmaceutical targets
9.  Neurobiological foundations of multisensory integration in people with autism spectrum disorders: the role of the medial prefrontal cortex 
This review aims to relate the sensory processing problems in people with autism spectrum disorders (ASD), especially multisensory integration (MSI), to the role of the medial prefrontal cortex (mPFC) by exploring neuroanatomical findings; brain connectivity and Default Network (DN); global or locally directed attention; and temporal multisensory binding. The mPFC is part of the brain’s DN, which is deactivated when attention is focused on a particular task and activated on rest when spontaneous cognition emerges. In those with ASD, it is hypoactive and the higher the social impairment the greater the atypical activity. With an immature DN, cross-modal integration is impaired, resulting in a collection of disconnected fragments instead of a coherent global perception. The deficit in MSI may lie in the temporal synchronization of neural networks. The time interval in which the stimulation of one sensory channel could influence another would be higher, preventing integration in the typical shorter time range. Thus, the underconnectivity between distant brain areas would be involved in top-down information processes (relying on global integration of data from different sources) and would enhance low level perception processes such as over focused attention to sensory details.
doi:10.3389/fnhum.2014.00970
PMCID: PMC4255523  PMID: 25538597
autism spectrum disorders (ASD); multisensory integration; medial prefrontal cortex (mPFC); default network; temporal multisensory binding
10.  Effects of nitrogen nutrition on the synthesis and deposition of the ω-gliadins of wheat 
Annals of Botany  2013;113(4):607-615.
Background and Aims
The ω-gliadin storage proteins of wheat are of interest in relation to their impact on grain processing properties and their role in food allergy, particularly the ω-5 sub-group and wheat-dependent exercise-induced anaphylaxis. The ω-gliadins are also known to be responsive to nitrogen application. This study therefore compares the effects of cultivar and nitrogen availability on the synthesis and deposition of ω-gliadins in wheat grown under field conditions in the UK, including temporal and spatial analyses at the protein and transcript levels.
Methods
SDS–PAGE, western blotting and N-terminal amino acid sequencing were used to compare the patterns of ω-gliadin components in mature grain of six British wheat (Triticum aestivum) cultivars and their accumulation during the development of grain grown in field plots with varying nitrogen supply. Changes in gene expression during development were determined using real-time reverse transcription–PCR (RT–PCR). Spatial patterns of gene expression and protein accumulation were determined by in situ hybridization and immunofluorescence microscopy, respectively.
Key Results
Two patterns of ω-gliadins were identified in the six cultivars, including both monomeric ‘gliadin’ proteins and subunits present in polymeric ‘glutenin’ fractions. Increasing the level of nitrogen fertilizer in field plots resulted in increased expression of ω-gliadin transcripts and increased proportions of ω-5 gliadins. Nitrogen supply also affected the spatial patterns of ω-gliadin synthesis and deposition, which were differentially increased in the outer layers of the starchy endosperm with high levels of nitrogen.
Conclusions
Wheat ω-gliadins vary in amount and composition between cultivars, and in their response to nitrogen supply. Their spatial distribution is also affected by nitrogen supply, being most highly concentrated in the sub-aleurone cells of the starchy endosperm under higher nitrogen availability.
doi:10.1093/aob/mct291
PMCID: PMC3936585  PMID: 24344140
Wheat; Triticum aestivum; storage protein; nitrogen; ω-gliadin; RNA in situ hybridization; immunolocalization; protein bodies; wheat allergy
11.  The p38–PGC-1α–irisin–betatrophin axis 
Adipocyte  2013;3(1):67-68.
The discovery of irisin as a novel and promising peptidic hormone has raised hopes regarding the hypothesis that irisin may provide additional benefits, not only for obesity and diabetes, but also for a wide range of pathological conditions since this hormone may prove to be therapeutically and clinically beneficial. In addition, a new hormone, betatrophin, has recently been identified by Yi and coworkers. Both hormones are connected by a new pathway clearly involved in insulin resistance. We hypothesize here how these hormones may be linked and their possible implications in both aged-reduced restricted regenerative capacity and dedifferentiated β cells of diabetic patients.
doi:10.4161/adip.27370
PMCID: PMC3917937  PMID: 24575373
diabetes; metabolism; obesity; oxidative stress; β cells
12.  Integrin-assisted drug delivery of nano-scaled polymer therapeutics bearing paclitaxel 
Biomaterials  2011;32(15):10.1016/j.biomaterials.2011.01.073.
Angiogenesis plays a prominent role in cancer progression. Anti-angiogenic therapy therefore, either alone or in combination with conventional cytotoxic therapy, offers a promising therapeutic approach. Paclitaxel (PTX) is a widely-used potent cytotoxic drug that also exhibits anti-angiogenic effects at low doses. However, its use, at its full potential, is limited by severe side effects. Here we designed and synthesized a targeted conjugate of PTX, a polymer and an integrin-targeted moiety resulting in a polyglutamic acid (PGA)-PTX-E-[c(RGDfK)2] nano-scaled conjugate. Polymer conjugation converted PTX to a macromolecule, which passively targets the tumor tissue exploiting the enhanced permeability and retention effect, while extravasating via the leaky tumor neovasculature. The cyclic RGD peptidomimetic enhanced the effects previously seen for PGA-PTX alone, utilizing the additional active targeting to the αvβ3 integrin overexpressed on tumor endothelial and epithelial cells. This strategy is particularly valuable when tumors are well-vascularized, but they present poor vascular permeability. We show that PGA is enzymatically-degradable leading to PTX release under lysosomal acidic pH. PGA-PTX-E-[c(RGDfK)2] inhibited the growth of proliferating αvβ3-expressing endothelial cells and several cancer cells. We also showed that PGA-PTX-E-[c(RGDfK)2] blocked endothelial cells migration towards vascular endothelial growth factor; blocked capillary-like tube formation; and inhibited endothelial cells attachment to fibrinogen. Orthotopic studies in mice demonstrated preferential tumor accumulation of the RGD-bearing conjugate, leading to enhanced antitumor efficacy and a marked decrease in toxicity as compared with free PTX-treated mice.
doi:10.1016/j.biomaterials.2011.01.073
PMCID: PMC3857101  PMID: 21376390
Angiogenesis; polymer therapeutics; Polyglutamic acid; paclitaxel; RGD peptidomimetic; integrin
13.  Vitamin C Supplementation Does not Improve Hypoxia-Induced Erythropoiesis 
High Altitude Medicine & Biology  2012;13(4):269-274.
Abstract
Martinez-Bello,Vladimir E., Fabian Sanchis-Gomar, Daniel Martinez-Bello, Gloria Olaso-Gonzalez, Mari Carmen Gomez-Cabrera, and Jose Viña. Vitamin C Supplementation Does Not Improve Hypoxia-Induced Erythropoiesis. High Alt Med Biol 13:269–274, 2012.—Hypoxia induces reactive oxygen species production. Supplements with antioxidant mixtures can compensate for the decline in red cell membrane stability following intermittent hypobaric hypoxia by decreasing protein and lipid oxidation. We aimed to determine whether supplementation with vitamin C is implicated in the regulation of erythropoiesis and in the oxygen-carrying capacity of the blood, and also whether antioxidant supplementation prevents the oxidative stress associated to intermittent hypoxia. Twenty-four male Wistar rats were randomly divided into four experimental groups: normoxia control (n=6), normoxia + vitamin C (n=6), hypoxia control (12 h pO2 12%/12 h pO2 21%) (n=6), and hypoxia + vitamin C (n=6). Animals were supplemented with vitamin C at a dose of 250 mg·kg−1·day−1 for 21 days. Red blood cell count, hemoglobin, hematocrit, reticulocytes, erythropoietin, and oxidative stress parameters such as malondialdehyde and protein oxidation in plasma were analyzed at two different time points: basal sample (day zero) and final sample (day 21). Similar RBC, Hb, Hct, and Epo increments were observed in both hypoxic groups regardless of the vitamin C supplementation. There was no change on MDA levels after intermittent hypoxic exposure in any experimental group. However, we found an increase in plasma protein oxidation in both hypoxic groups. Vitamin C does not affect erythropoiesis and protein oxidation in rats submitted to intermittent hypoxic exposure.
doi:10.1089/ham.2012.1028
PMCID: PMC3533831  PMID: 23270444
hematocrit; hemoglobin; red blood cells; oxidative stress; antioxidants
14.  The Year 2011 in Interventional Cardiology 
doi:10.5935/abc.20130238
PMCID: PMC4106817
Percutaneous Coronary Intervention; Angioplasty; Aortic Valve Stenosis
15.  Phase II Open-Label Study to Assess Efficacy and Safety of Lenalidomide in Combination with Cetuximab in KRAS-Mutant Metastatic Colorectal Cancer 
PLoS ONE  2013;8(11):e62264.
This study aimed to assess the efficacy and safety of combination treatment with lenalidomide and cetuximab in KRAS-mutant metastatic colorectal cancer patients. This was a phase II multicenter, open-label trial comprising a safety lead-in phase (phase IIa) to determine the maximum tolerated dose, and a randomized proof of concept phase (phase IIb) to determine the response rate of lenalidomide plus cetuximab combination therapy. Phase IIa treatment comprised oral lenalidomide (starting dose 25 mg/day) and intravenous cetuximab (400 mg/m2 followed by weekly 250 mg/m2) in 28-day cycles. In phase IIb patients were randomized to either the phase IIa treatment schedule of lenalidomide plus cetuximab combination therapy or lenalidomide 25 mg/day monotherapy. Eight patients were enrolled into phase IIa. One patient developed a dose-limiting toxicity and the maximum tolerated dose of lenalidomide was determined at 25 mg/day. Forty-three patients were enrolled into phase IIb proof of concept. Best response was stable disease in 9 patients and study enrollment was terminated prematurely due to lack of efficacy in both treatment arms and failure to achieve the planned response objective. The majority of adverse events were grade 1 and 2. In both phases, the adverse events most commonly attributed to any study drugs were fatigue, rash and other skin disorders, diarrhea, nausea, and stomatitis. Thirty-nine deaths occurred; none was related to study drug. The combination of lenalidomide and cetuximab appeared to be well tolerated but did not have clinically meaningful activity in KRAS-mutant metastatic colorectal cancer patients.
Trial Registration
Clinicaltrials.gov NCT01032291
doi:10.1371/journal.pone.0062264
PMCID: PMC3823943  PMID: 24244261
16.  Acute Coronary Syndromes in 2011 and 2012 
doi:10.5935/abc.2013218
PMCID: PMC4081172  PMID: 24343553
Acute Coronary Syndrome; Coronary Balloon Angioplasty; Myocardial Infarction
17.  Intraoral Schwannomas: Presentation of a series of 12 cases 
Introduction: Schwannomas are benign and not very frequent tumors of the peripheral nerves, derived from the nerve supporting Schwann cells. Study Design: Data were collected on the clinical manifestations (sex, age), location, size and symptonts of the lesions as well as the evolution time and the initial (presumption) diagnosis. Results: Twelve patients were documented, with a mean age of 29,5 ± 12,1 years (range 16-50) and a balanced gender distribution. The mean duration of the lesions was 42,17± 45,3 months. The lesion located in the floor of the mouth was the largest tumor, measuring about 4 cm in maximum diameter, while the average size of the 12 schwannomas was 2.04± 1.1 cm. Conclusion: We present 12 oral schwannomas diagnosed and treated over a period of 10 years.
Key words:Schwannomas, oral benign tumor, neurilemmoma.
doi:10.4317/jced.51176
PMCID: PMC3892247  PMID: 24455080
18.  Framingham Risk Score for Prediction of Cardiovascular Diseases: A Population-Based Study from Southern Europe 
PLoS ONE  2013;8(9):e73529.
Background
The question about what risk function should be used in primary prevention remains unanswered. The Framingham Study proposed a new algorithm based on three key ideas: use of the four risk factors with the most weight (cholesterol, blood pressure, diabetes and smoking), prediction of overall cardiovascular diseases and incorporating the concept of vascular age. The objective of this study was to apply this new function in a cohort of the general non Anglo-Saxon population, with a 10-year follow-up to determine its validity.
Methods
The cohort was studied in 1992-94 and again in 2004-06. The sample comprised 959 randomly-selected persons, aged 30-74 years, who were representative of the population of Albacete, Spain. At the first examination cycle, needed data for the new function were collected and at the second examination, data on all events were recorded during the follow-up period. Discrimination was studied with ROC curves. Comparisons of prediction models and reality in tertiles (Hosmer-Lemeshow) were performed, and the individual survival functions were calculated.
Results
The mean risks for women and men, respectively, were 11.3% and 19.7% and the areas under the ROC curve were 0.789 (95%CI, 0.716-0.863) and 0.780 (95%CI, 0.713-0.847) (P<0.001, both). Cardiovascular disease events occurred in the top risk tertiles. Of note were the negative predictive values in both sexes, and a good specificity in women (85.6%) and sensitivity in men (79.1%) when their risk for cardiovascular disease was high. This model overestimates the risk in older women and in middle-aged men. The cumulative probability of individual survival by tertiles was significant in both sexes (P<0.001).
Conclusions
The results support the proposal for “reclassification” of Framingham. This study, with a few exceptions, passed the test of discrimination and calibration in a random sample of the general population from southern Europe.
doi:10.1371/journal.pone.0073529
PMCID: PMC3764050  PMID: 24039972
19.  Differential mortality association of loop diuretic dosage according to blood urea nitrogen and carbohydrate antigen 125 following a hospitalization for acute heart failure 
European Journal of Heart Failure  2012;14(9):974-984.
Aims
Recent observations in chronic stable heart failure suggest that high-dose loop diuretics (HDLDs) have detrimental prognostic effects in patients with high blood urea nitrogen (BUN), but recent findings have also indicated that diuretics may improve renal function. Carbohydrate antigen 125 (CA125) has been shown to be a surrogate of systemic congestion. We sought to explore whether BUN and CA125 modulate the mortality risk associated with HDLDs following a hospitalization for acute heart failure (AHF).
Methods and results
We analysed 1389 consecutive patients discharged for AHF. CA125 and BUN were measured at a mean of 72 ± 12 h after admission. HDLDs (≥120 mg/day in furosemide equivalent dose) were interacted to a four-level variable according to CA125 (>35 U/mL) and BUN (above the median), and related to all-cause mortality. At a median follow-up of 21 months, 561 (40.4%) patients died. The use of HDLDs was independently associated with increased mortality [hazard ratio (HR) 1.23, 95% confidence interval (CI) 1.01–1.50], but this association was not homogeneous across CA125–BUN categories (P for interaction <0.001). In patients with normal CA125, use of HDLDs was associated with high mortality if BUN was above the median (HR 2.29, 95% 1.51–3.46), but not in those with BUN below the median (HR 1.22, 95% CI 0.73–2.04). Conversely, in patients with high CA125, HDLDs showed an association with increased survival if BUN was above the median (HR 0.73, 95% CI 0.55–0.98) but was associated with increased mortality in those with BUN below the median (HR 1.94, 95% CI 1.36–2.76).
Conclusion
The risk associated with HDLDs in patients after hospitalization for AHF was dependent on the levels of BUN and CA125. The information provided by these two biomarkers may be helpful in tailoring the dose of loop diuretics at discharge for AHF.
doi:10.1093/eurjhf/hfs090
PMCID: PMC3423949  PMID: 22700856
Loop diuretics; Mortality; Acute heart failure; Carbohydrate antigen 125; Blood urea nitrogen
20.  Towards germline gene therapy of inherited mitochondrial diseases 
Nature  2012;493(7434):627-631.
Mutations in mitochondrial DNA (mtDNA) are associated with serious human diseases and inherited from mother's eggs. Here we investigated the feasibility of mtDNA replacement in human oocytes by spindle transfer (ST). Of 106 human oocytes donated for research, 65 were subjected to reciprocal ST and 33 served as controls. Fertilization rate in ST oocytes (73%) was similar to controls (75%). However, a significant portion of ST zygotes (52%) displayed abnormal fertilization as determined by irregular number of pronuclei. Among normally fertilized ST zygotes, blastocyst development (62%) and embryonic stem cell (ESC) isolation (38%) rates were comparable to controls. All ESC lines derived from ST zygotes displayed normal euploid karyotypes and contained exclusively donor mtDNA. The mtDNA can be efficiently replaced in human oocytes. Although some ST oocytes displayed abnormal fertilization, remaining embryos were capable of developing to blastocysts and producing ESCs similar to controls.
doi:10.1038/nature11647
PMCID: PMC3561483  PMID: 23103867
21.  Pathogenic Potential of Bacillus cereus Strains as Revealed by Phenotypic Analysis 
Journal of Clinical Microbiology  2013;51(1):320-323.
The Bacillus cereus pathogenic spectrum ranges from strains used as probiotics to human-lethal strains. However, prediction of the pathogenic potential of a strain remains difficult. Here, we show that food poisoning and clinical strains can be differentiated from harmless strains on the basis of host colonization phenotypes.
doi:10.1128/JCM.02848-12
PMCID: PMC3536244  PMID: 23135929
22.  Age associated low mitochondrial biogenesis may be explained by lack of response of PGC-1α to exercise training 
Age  2011;34(3):669-679.
Low mitochondriogenesis is critical to explain loss of muscle function in aging and in the development of frailty. The aim of this work was to explain the mechanism by which mitochondriogenesis is decreased in aging and to determine to which extent it may be prevented by exercise training. We used aged rats and compared them with peroxisome proliferator-activated receptor-γ coactivator-1α deleted mice (PGC-1α KO). PGC-1α KO mice showed a significant decrease in the mitochondriogenic pathway in muscle. In aged rats, we found a loss of exercise-induced expression of PGC-1α, nuclear respiratory factor-1 (NRF-1), and of cytochrome C. Thus muscle mitochondriogenesis, which is activated by exercise training in young animals, is not in aged or PGC-1α KO ones. Other stimuli to increase PGC-1α synthesis apart from exercise training, namely cold induction or thyroid hormone treatment, were effective in young rats but not in aged ones. To sum up, the low mitochondrial biogenesis associated with aging may be due to the lack of response of PGC-1α to different stimuli. Aged rats behave as PGC-1α KO mice. Results reported here highlight the role of PGC-1α in the loss of mitochondriogenesis associated with aging and point to this important transcriptional coactivator as a target for pharmacological interventions to prevent age-associated sarcopenia.
doi:10.1007/s11357-011-9264-y
PMCID: PMC3337936  PMID: 21590341
Sarcopenia; Exercise; Oxidative stress; Aging; Cytochrome C; Gene knockout; Life Sciences; Molecular Medicine; Geriatrics/Gerontology; Cell Biology
23.  The Pore-Forming Haemolysins of Bacillus Cereus: A Review 
Toxins  2013;5(6):1119-1139.
The Bacillus cereus sensu lato group contains diverse Gram-positive spore-forming bacteria that can cause gastrointestinal diseases and severe eye infections in humans. They have also been incriminated in a multitude of other severe, and frequently fatal, clinical infections, such as osteomyelitis, septicaemia, pneumonia, liver abscess and meningitis, particularly in immuno-compromised patients and preterm neonates. The pathogenic properties of this organism are mediated by the synergistic effects of a number of virulence products that promote intestinal cell destruction and/or resistance to the host immune system. This review focuses on the pore-forming haemolysins produced by B. cereus: haemolysin I (cereolysin O), haemolysin II, haemolysin III and haemolysin IV (CytK). Haemolysin I belongs to the cholesterol-dependent cytolysin (CDC) family whose best known members are listeriolysin O and perfringolysin O, produced by L. monocytogenes and C. perfringens respectively. HlyII and CytK are oligomeric ß-barrel pore-forming toxins related to the α-toxin of S. aureus or the ß-toxin of C. perfringens. The structure of haemolysin III, the least characterized haemolytic toxin from the B. cereus, group has not yet been determined.
doi:10.3390/toxins5061119
PMCID: PMC3717773  PMID: 23748204
B. cereus; haemolysins; cereolysin O; haemolysin II; haemolysin III; cytotoxin K; PlcR
24.  Molecular Electronic Coupling Controls Charge Recombination Kinetics in Organic Solar Cells of Low Bandgap Diketopyrrolopyrrole, Carbazole, and Thiophene Polymers 
Low-bandgap diketopyrrolopyrrole- and carbazole-based polymer bulk-heterojunction solar cells exhibit much faster charge carrier recombination kinetics than that encountered for less-recombining poly(3-hexylthiophene). Solar cells comprising these polymers exhibit energy losses caused by carrier recombination of approximately 100 mV, expressed as reduction in open-circuit voltage, and consequently photovoltaic conversion efficiency lowers in more than 20%. The analysis presented here unravels the origin of that energy loss by connecting the limiting mechanism governing recombination dynamics to the electronic coupling occurring at the donor polymer and acceptor fullerene interfaces. Previous approaches correlate carrier transport properties and recombination kinetics by means of Langevin-like mechanisms. However, neither carrier mobility nor polymer ionization energy helps understanding the variation of the recombination coefficient among the studied polymers. In the framework of the charge transfer Marcus theory, it is proposed that recombination time scale is linked with charge transfer molecular mechanisms at the polymer/fullerene interfaces. As expected for efficient organic solar cells, small electronic coupling existing between donor polymers and acceptor fullerene (Vif < 1 meV) and large reorganization energy (λ ≈ 0.7 eV) are encountered. Differences in the electronic coupling among polymer/fullerene blends suffice to explain the slowest recombination exhibited by poly(3-hexylthiophene)-based solar cells. Our approach reveals how to directly connect photovoltaic parameters as open-circuit voltage to molecular properties of blended materials.
doi:10.1021/jp402751v
PMCID: PMC3646405  PMID: 23662167
25.  Pseudotumors and tumors of the temporomandibular joint. A review 
Objective: To review the pseudotumors and tumors of the temporomandibular joint (TMJ) published in journals included in Journal Citation Reports (JCR), and to evaluate whether there are clinical and radiological signs capable of differentiating between pseudotumors and tumors and between malignant and benign tumors. Material and Methods: A systematic Medline search was made of clinical cases of tumors and pseudotumors of the TMJ covering a 20-year period and published in journals included in JCR. Only cases with histological confirmation were included. A description is provided of the general characteristics of TMJ tumors, with comparison of the clinical, diagnostic, therapeutic and evolutive variables referred to pseudotumors, benign tumors and malignant tumors. Results: We identified 285 TMJ tumors published in 181 articles of 15 journals. The most frequent lesions were pseudotumors (synovial chondromatosis, pigmented villonodular synovitis, eosinophilic granuloma and osteochondroma). The mean age was 42 years and one month ± 16 years and two months. Tumors were more common in females. The mean time from symptoms onset to consultation was 30 months and 8 days ± 41 months and 9 days, and almost 19.6% of the cases initially had been diagnosed and treated as TMJ dysfunction. The most frequent clinical manifestations were pain, swelling and the limitation of joint movements. The most common radiological findings in the case of benign and malignant lesions were radiopacities and radiotransparencies, respectively. No panoramic X-ray alterations were observed in 14.6% of the benign tumors and in 7.7% of the malignant lesions. Surgery was the usual form of treatment. Sequelae were recorded in 18.2% of the cases, with tumor relapse in 9.1%. The four-year survival rate in the case of malignant tumors was 72.2%.
Key words:Tumor, temporomandibular joint, metaplasia, pseudotumor, condyle.
doi:10.4317/medoral.18799
PMCID: PMC3668863  PMID: 23385515

Results 1-25 (101)