Vitamin D₃ improves respiratory adjustment to fatigue and H-reflex responses in paraplegic adult rats

We previously demonstrated that vitamin D₂ (ergocalciferol) triggers axon regeneration in a rat model of peripheral nerve transection. In order to confirm the regenerative potential of this neuroactive steroid, we performed a study in which vitamin D₃ (cholecalciferol) was delivered at various doses to paralytic rats. After spinal cord compression at the T10 level, rats were given orally either vehicle or vitamin D₃ at the dose of 50 IU/kg/day or 200 IU/kg/day. Three months later, M and H-waves were recorded from rat Tibialis anterior muscle in order to quantify the maximal H-reflex (H(max)) amplitude. We also monitored the ventilatory frequency during an electrically induced muscle fatigue known to elicit the muscle metaboreflex and an increase in respiratory rate. Spinal cords were then collected, fixed and immunostained with an anti-neurofilament antibody. We show here that vitamin D-treated animals display an increased number of axons within the lesion site. In addition, rats supplemented with vitamin D₃ at the dose of 200 IU/kg/day exhibit (i) an improved breathing when hindlimb was electrically stimulated; (ii) an H-reflex depression similar to control animals and (iii) an increased number of axons within the lesion and in the distal area. Our data confirm that vitamin D is a potent molecule that can be used for improving neuromuscular adaptive mechanisms and H-reflex responses.

Individualized higher dose of 70-75 Gy using five-fraction robotic stereotactic radiotherapy for non-small-cell lung cancer: a feasibility study

OBJECTIVE

To determine whether robotic stereotactic radiotherapy of 70-75 Gy delivered in five fractions results in an improved therapeutic ratio, compared with three fractions, in the treatment of peripheral non-small-cell lung cancer (NSCLC), in which case doses of up to 85 Gy in five fractions may be feasible.

MATERIALS AND METHODS

Between December 2006 and May 2010, 20 patients (9 female, 11 male, aged 65 to 88) were treated using the CyberKnife® Robotic Radiosurgery System for NSCLC with doses ranging from 67 Gy to 75 Gy based on location, histopathological type, grade of histopathological differentiation, tumor diameter/volume, and normal tissue constraints, with the doses being delivered in five fractions over 5 to 8 days. Tumor diameters ranged from 1.5 cm to 3.4 cm (median: 2.5 cm). Patients with Stage I to IV NSCLC were treated, and the results and observations were analyzed for clinical characteristics and outcomes including toxicity. All patients, except one who had refused surgery, had co-morbid conditions that precluded a lobectomy.

RESULTS

Twenty patients were followed every three months by positron emission tomography/computed tomography (PET/CT). Mean follow-up was 23 months (range: four to 58 months). Local control was achieved in all treated tumors. Three patients expired, and three developed new regional metastases, none of which was within the planning target volume (PTV). The remainder of the patients demonstrated no evidence of recurrence or continued growth detectable by PET/CT. There was no toxicity above Grade 1.

CONCLUSIONS

It is feasible to treat peripheral NSCLC with individualized maximal tolerable doses ranging from 67 Gy to 75 Gy in five fractions chosen on the basis of location, histopathological type, grade of histopathological differentiation, tumor diameter/volume, and normal tissue constraints.

The changing face of hospitalisation due to gastrointestinal bleeding and perforation

BACKGROUND

Temporal changes in the incidence of cause-specific gastrointestinal (GI) complications may be one of the factors underlying changing medical practice patterns.

AIM

To report temporal changes in the incidence of five major causes of specific gastrointestinal (GI) complication events.

METHODOLOGY

Population-based study of patients hospitalised due to GI bleeding and perforation from 1996 to 2005 in Spain. We report crude rates, and estimate regression coefficients of temporal trends, severity and recorded drug use for five frequent GI events. GI hospitalisation charts were validated by independent review of large random samples.

RESULTS

The incidence per 100 000 person-years of hospitalisations due to upper GI ulcer bleeding and perforation decreased over time [from 54.6 and 3.9 in 1996 (R² = 0.944) to 25.8 and 2.9 in 2005 (R² = 0.410) respectively]. On the contrary, the incidence per 100 000 person-years of colonic diverticular and angiodysplasia bleeding increased over time [3.3 and 0.9 in 1996 (R² = 0.443) and 8.0 and 2.6 in 2005 (R² = 0.715) respectively]. A small increasing trend was observed for the incidence per 100 000 person-years of intestinal perforations (from 1.5 to 2.3 events). Based on data extracted from the validation process, recent recorded drug intake showed an increased frequency of anticoagulants with colonic diverticular and angiodysplasia bleeding, whereas NSAID and low-dose aspirin use were more prevalent in peptic ulcer bleeding and colonic diverticular bleeding respectively.

CONCLUSIONS

From 1996 to 2005, hospitalisations due to peptic ulcer bleeding and perforation have decreased significantly, whereas the number of cases of colonic diverticular and angiodysplasia bleeding have increased.

Liver transplantation in a patient treated by sorafenib for hepatocellular carcinoma

Sorafenib is a multikinase inhibitor currently used in the palliative treatment of advanced hepatocellular carcinoma. In patients with small hepatocellular carcinoma, sorafenib could be suggested as neoadjuvant therapy to control tumor growth during waiting time for liver transplantation. However, up to now, safety of liver transplantation in patients undergoing sorafenib treatment is not known. Herein, we report a case of successful liver transplantation in a patient treated by sorafenib for hepatocellular carcinoma. In this patient, liver transplantation was performed safely and histological examination of explanted liver evidenced complete necrosis of the largest tumor nodule.

TP53INP1 decreases pancreatic cancer cell migration by regulating SPARC expression

Tumor protein 53 induced nuclear protein 1 (TP53INP1) is a p53 target gene that induces cell growth arrest and apoptosis by modulating p53 transcriptional activity. TP53INP1 interacts physically with p53 and is a major player in the p53-driven oxidative stress response. Previously, we demonstrated that TP53INP1 is downregulated in an early stage of pancreatic cancerogenesis and when restored is able to suppress pancreatic tumor development. TP53INP1 downregulation in pancreas is associated with an oncogenic microRNA miR-155. In the present work, we studied the effects of TP53INP1 on cell migration. We found that TP53INP1 inactivation correlates with increased cell migration both in vivo and in vitro. The impact of TP53INP1 expression on cell migration was studied in different cellular contexts: mouse embryonic fibroblast and different pancreatic cancer cell lines. Its expression decreases cell migration by the transcriptional downregulation of secreted protein acidic and rich in cysteine (SPARC). SPARC is a matrix cellular protein, which governs diverse cellular functions and has a pivotal role in regulating cell-matrix interactions, cellular proliferation and migration. SPARC was also showed to be upregulated in normal pancreas and in pancreatic intraepithelial neoplasia lesions in a pancreatic adenocarcinoma mouse model only in the TP53INP1-deficient animals. This novel TP53INP1 activity on the regulation of SPARC expression could explain in part its tumor suppressor function in pancreatic adenocarcinoma by modulating cellular spreading during the metastatic process.

Comparison of [¹¹¹In]pentetreotide-SPECT and [¹⁸F]FDOPA-PET in the localization of extra-adrenal paragangliomas: the case for a patient-tailored use of nuclear imaging modalities

AIMS AND METHODS

The aim of this prospective study was to compare the diagnostic value of [¹⁸F]FDOPA-PET and [¹¹¹In]pentetreotide-SPECT somatostatin receptor scintigraphy (SRS) in patients with nonmetastatic extra-adrenal paragangliomas (PGLs). Twenty-five consecutive unrelated patients who were known or suspected of having nonmetastatic extra-adrenal PGLs were prospectively evaluated with SRS and [¹⁸F]FDOPA-PET. ¹³¹I-MIBG and [¹⁸F]FDG-PET were added to the work-up in patients with a personal or familial history of PGL, predisposing mutations, abdominal PGLs, metanephrine hypersecretion and abdominal foci on SRS and/or [¹⁸F]FDOPA-PET.

RESULTS

SRS correctly detected 23/45 lesions of which 20 were head or neck lesions (H&N) and 3 were abdominal lesions. [¹⁸F]FDOPA-PET detected significantly more lesions than SRS (39/45, P < 0·001). Both SRS and ¹⁸F-DOPA-PET detected significantly more H&N than abdominal lesions (66·7% vs 20%, P = 0·003 and 96·7% vs 67%, P = 0·012, respectively). In two patients with the succinate dehydrogenase D (SDHD) mutation, [¹⁸F]FDOPA-PET missed five abdominal PGLs which were detected by the combination of SRS, [¹³¹I]MIBG and [¹⁸F]FDG-PET. A lesion-based analysis using a forward stepwise logistic regression model demonstrates that size ≤ 10 mm (P = 0·002) and abdominal lesions (P = 0·031) were independently associated with "[¹⁸F]FDOPA-PET diagnosis only". In turn, a previous history of surgery and/or the presence of germline mutation was associated with lower lesion size (P = 0·001).

CONCLUSIONS

The sensitivity of SRS for localizing parasympathetic PGLs is lower than originally reported, and [¹⁸F]FDOPA-PET is better than SRS for localizing small lesions. SRS should be replaced by [¹⁸F]FDOPA-PET as the first-line imaging procedure in H&N PGL, especially in patients at risk of multifocal disease (predisposing mutations and or previous history of surgery).

Genome size dynamics in Artemisia L. (Asteraceae): following the track of polyploidy

Polyploidy is a key factor in the evolution of higher plants and plays an important role in the variation of plant genomes, leading to speciation in some cases. During polyploidisation, different balancing processes take place at the genomic level that can promote variation in nuclear DNA content. We estimated genome size using flow cytometry in 84 populations of 67 Artemisia species and one population of Crossostephium chinense. A total of 73 sequences of nrDNA ITS and 3'-ETS were newly generated and analysed, together with previously published sequences, to address the evolution of genome size in a phylogenetic framework. Differences in 2C values were detected among some lineages, as well as an increase of genome size heterogeneity in subgenera whose phylogenetic relationships are still unclear. We confirmed that the increase in 2C values in Artemisia polyploids was not proportional to ploidy level, but 1Cx genome size tended to decrease significantly when high ploidy levels were reached. The results lead us to hypothesise that genome size in polyploids tends to a maximum as it follows saturation behaviour, in agreement with the Michaelis-Menten model. We tested different arithmetic functions with our dataset that corroborated a non-linear relationship of genome size increase in polyploids, allowing us to suggest a theoretical upper limit for the DNA content of this genus.

Wood degradation by white rot fungi: cytochemical studies using lignin peroxidase-immunoglobulin-gold complexes

Using an anti-lignin peroxidase antiserum-protein A-gold complex, we found lignin peroxidase mainly intracellularly in several white rot fungi colonizing sawdust under laboratory conditions. This enzyme was also present in fungi found in naturally decayed wood. However, in all cases, lignin peroxidase was located mainly inside the fungal cells. Labeled lignin peroxidase did not bind to the lignocellulosic samples tested, with the exception of poplar milled-wood lignin. These results are discussed in relation to the role of lignin peroxidase during wood degradation.

Tumor protein p53-induced nuclear protein (TP53INP1) expression in medullary thyroid carcinoma: a molecular guide to the optimal extent of surgery?

BACKGROUND

Medullary thyroid cancer (MTC) is characterized by early regional lymph node metastasis, the presence of which represents a critical obstacle to cure. At present no molecular markers have been successfully integrated into the clinical care of sporadic MTC. The present study was designed to evaluate TP53INP1 expression in MTC and to assess its ability to guide the surgeon to the optimal extent of surgery performed with curative intent.

METHODS

Thirty-eight patients with sporadic MTC were evaluated. TP53INP1 immunoexpression was studied on embedded paraffin material and on cytological smears.

RESULTS

TP53INP1 was expressed in normal C cells, in C-cell hyperplasia, and in 57.9% of MTC. It was possible to identify two groups of MTC according to the proportion of TP53INP1 expressing tumor cells: group 1 from 0% to <50% and group 2 from 50% to 100% of positive cells. Patients with a decreased expression of TP53INP1 (group 1) had a lower rate of nodal metastasis (18.8% versus 63.4% in group 2; P = 0.009), with only minimal lymph node involvement per N1 patient (2.7% of positive lymph nodes versus 22.9%; P < 0.001) and better outcomes (100% of biochemical cure versus 55.5%; P < 0.001). Patients with distant metastases were only observed in group 2. Cytological samples exhibit similar results to their embedded counterparts.

CONCLUSIONS

TP53INP1 immunoexpression appears to be a clinical predictor of lymph node metastasis in MTC. The evaluation of TP53INP1 expression may guide the extent of lymph node dissection in the clinically node-negative neck. These findings require prospective validation.

Organ-specific shifts in mtDNA heteroplasmy following systemic delivery of a mitochondria-targeted restriction endonuclease

Most pathogenic mtDNA mutations are heteroplasmic and there is a clear correlation between high levels of mutated mtDNA in a tissue and pathology. We have found that in vivo double strand breaks (DSB) in mtDNA lead to digestion of cleaved mtDNA and replication of residual mtDNA. Therefore, if DSB could be targeted to mutations in mtDNA, mutant genomes could be eliminated and the wild-type mtDNA would repopulate the cells. This can be achieved by using mitochondria-targeted restriction endonucleases as a means to degrade specific mtDNA haplotypes in heteroplasmic cells or tissues. In the present work we investigated the potential of systemic delivery of mitochondria-targeted restriction endonucleases to reduce the proportion of mutant mtDNA in specific tissues. Using the asymptomatic NZB/BALB mtDNA heteroplasmic mouse as a model, we found that a mitochondria-targeted ApaLI (that cleaves BALB mtDNA at a single site and does not cleave NZB mtDNA) increased the proportion of NZB mtDNA in target tissues. This was observed in heart, using a cardiotropic adeno-associated virus type-6 (AAV6) and in liver, using the hepatotropic adenovirus type-5 (Ad5). No mtDNA depletion or loss of cytochrome c oxidase activity was observed in any of these tissues. These results demonstrate the potential of systemic delivery of viral vectors to specific organs for the therapeutic application of mitochondria-targeted restriction enzymes in mtDNA disorders.

Learning-dependent neurogenesis in the olfactory bulb determines long-term olfactory memory

Inhibitory interneurons of the olfactory bulb are subjected to permanent adult neurogenesis. Their number is modulated by learning, suggesting that they could play a role in plastic changes of the bulbar network associated with olfactory memory. Adult male C57BL/6 mice were trained in an associative olfactory task, and we analyzed long-term retention of the task 5, 30, and 90 d post-training. In parallel, we assessed the fate of these newborn cells, mapped their distribution in the olfactory bulb and measured their functional implication using the immediate early gene Zif268. In a second set of experiments, we pharmacologically modulated glutamatergic transmission and using the same behavioral task assessed the consequences on memory retention and neurogenesis. Finally, by local infusion of an antimitotic drug, we selectively blocked neurogenesis during acquisition of the task and looked at the effects on memory retention. First we demonstrated that retrieval of an associative olfactory task recruits the newborn neurons in odor-specific areas of the olfactory bulb selected to survive during acquisition of the task and that it does this in a manner that depends on the strength of learning. We then demonstrated that acquisition is not dependent on neurogenesis if long-term retention of the task is abolished by blocking neurogenesis. Adult-born neurons are thus involved in changes in the neural representation of an odor; this underlies long-term olfactory memory as the strength of learning is linked to the duration of this memory. Neurogenesis thus plays a crucial role in long-term olfactory memory.

Quantitative immunohistochemical expression of c Kit in breast carcinomas is predictive of patients' outcome

Background:

c Kit (CD117) expression in tissues has been reported as a relevant target for specific therapy in some human malignancies, but has been poorly documented in breast carcinomas

Methods:

The prognostic significance of c Kit in a series of 924 breast carcinomas (mean follow-up, 79 months) was investigated using standardised high-throughput quantitative densitometry of immunohistochemical precipitates in tissue microarrays.

Results:

c Kit was expressed in 14.7% breast carcinomas (and in 42 out of 586 node-negative tumours). In univariate analysis, (log-rank test) the score of c Kit expression correlated with poor patient outcome P=0.02 and particularly in node-negative cases (P=0.002). In multivariate Cox analysis, c Kit was an indicator of metastasis independent of 25 other concomitantly evaluated markers of prognosis. Logistic regression showed that c Kit ranked 10 out of 25 (P=0.041), and was included in a 10-marker signature that allowed 79.2% of the patients to be correctly classified in the metastatic or metastasis-free categories independently of hormone receptors and HER-2 status. Interestingly, c Kit was also a significant predictor of metastasis in node-negative tumours (2 out of 25 ranking, P<0.0001) and included in a six-marker signature of prognosis, correctly classifying 88.6% of the patients (P<0.0001).

Conclusion:

We concluded that, as assessed by quantitative immunohistochemistry, c Kit is an independent prognostic indicator that could also potentially serve as a target for specific therapy in breast carcinomas.

Combined inhibition of PAK7, MAP3K7 and CK2alpha kinases inhibits the growth of MiaPaCa2 pancreatic cancer cell xenografts

A panel of kinases whose inhibition increased apoptosis of pancreatic adenocarcinoma cells in vitro was recently established. The aim of this work was to observe in a mouse xenograft model whether inhibition of these kinases would alter pancreatic tumor growth. Rate of apoptosis, caspase-3 activity and cell viability were assessed in two pancreatic cancer cell lines, MiaPaCa2 and BxPC3, after inhibiting selected kinases by transfection of specific siRNAs. For in vivo experiments, MiaPaCa2 cells were injected into the pancreas of nude mice, where they formed tumors. Inhibition of kinases was obtained by repeated intraperitoneal (i.p.) injections of modified O-Methyl (OMe) siRNAs specific for the selected kinases. Tumor volumes were assessed after 21 days. Among selected kinases, PAK7, MAP3K7 and CK2alpha were those whose inhibition increased apoptosis the most in vitro. Simultaneous inhibition of two of them increased apoptosis up to five times. Moreover, inhibiting these kinases had little effect on 10 non-pancreatic cell lines, suggesting pancreatic specificity. In vivo, OMe-siRNAs induced significant but incomplete inhibition of kinase expression (45-75%). Nevertheless, such inhibition resulted in a twofold increase in caspase-3 activity in tumors and a strong reduction in tumor volume (about 75%). In vivo inhibition by OMe-siRNAs of three survival kinases apparently specific for pancreatic cancer cells, PAK7, MAP3K7 and CK2alpha, decreases significantly the growth of xenografted MiaPaCa2 cells. This strategy is therefore of potential clinical interest.

EVALUACIÓN DEL CULTIVO PROTEGIDO POR AGROTEXTIL EN LA CULTURA DE LECHUGA Y SU DESEMPEÑO EN DIFERENTES TIPOS DE APLICACIONES

RESUMEN El uso de cultivos protegidos con agrotextil es una técnica que se ha ido destacando a lo largo del tiempo, por su eficacia y facilidad de aplicación, principalmente en forma de cubiertas flotantes. El objetivo de este trabajo fue evaluar los diferentes métodos de aplicación del agrotextil blanco (17 g / m2) aplicado en forma de coberturas flotantes, asociadas a cubierturas de suelo utilizando agrotextil negro (45 g / m2) y mulching plástico negro (MP 25 µm) en el cultivo de lechuga. Los resultados mostraron variaciones significativas para masa fresca, lo que indica que el mejor método de aplicación fue en mulching plástico asociado al agrotextil en forma de cubierta flotante. El cultivo de lechuga mantenida sobre el agrotextil mostró un desarrollo vegetativo superior cuando se comparó en la parte aérea el número de hojas / planta y la altura, mostrando mejores resultados cuando se utilizó, en el tratamiento, la cobertura directamente sobre el cultivo o utilizando una guía de hilo de nylon como guía en comparación con el tratamiento sin cobertura agrotextil. Otro factor positivo fue el efecto de agrotextil como barrera física contra insectos plaga, reduciendo significativamente la infestación.

Strong coupling between pyramidal cell activity and network oscillations in the olfactory cortex

Oscillatory activity is a prominent characteristic of electrophysiological recordings in the olfactory system and has been proposed to play a key role in encoding olfactory representations. Studies in several systems have shown that some aspects of information coding involve characteristics that intertwine spikes and fast oscillations (in the beta and gamma range) of local field potentials (LFP). In the insect olfactory system, it has been proposed that oscillatory activity could provide a temporal link between cells. Following previous data, we have proposed that gamma band oscillations in mammals could subserve a gating function for the transfer of information between the olfactory bulb (OB) and the anterior piriform cortex (aPC), which are functionally coupled. In this study, we used an electrophysiological approach to investigate the temporal relationship between LFP gamma oscillations and single-unit activity by simultaneously recording LFP and single unit discharges in the rat aPC during odor evoked activity. Our data showed that mean spike discharges and gamma oscillatory bursts were synchronized with the same respiratory cycle epoch (around the inspiration/expiration transition). Temporal correlations between spikes and LFP revealed that cortical cell spikes were tightly phase-coupled with the peak of gamma oscillations and that this phase-coupling was not odor-dependent. Our results suggest that gamma oscillation may act as a temporal filter. Oscillatory phase-coupled spikes in the OB could act in increasing the probability of spike emission in the aPC cell during a narrow time-window, explaining the tight phase-coupling observed in the aPC. The role of spike-LFP phase-coupling as a binding function between odor features is discussed.

Patulin biodegradation using Pichia ohmeri and Saccharomyces cerevisiae

The effectiveness of Pichia ohmeri and Saccharomyces cerevisiae in the biodegradation of patulin was evaluated in vitro. Patulin is a toxin produced by Penicillium expansum, the predominant fungal contaminant in post-harvest apple. The biodegradation experiment was carried out in culture medium (Yeast Medium broth, YM) and commercial apple juice. These substrates were artificially contaminated with patulin previously produced by P. expansum strain 2 in malt extract broth and purified over a silica gel column. The YM broth was inoculated with P. ohmeri 158 with proved anti-P. expansum activity, whereas the apple juice was inoculated with dried Saccharomyces cerevisiae cells. The residual patulin in contaminated substrates was determined by reversed-phase HPLC. P. ohmeri 158 in YM broth degraded over 83% of the initial 223 µg (8.92 µg/ml) of patulin after incubation at 25 °C for two days under static conditions; after five days of incubation, this percentage was greater than 99%, and patulin levels fell below the limit of detection after 15 days. In the apple juices inoculated with 0.25 g/l of commercial dried S. cerevisiae cells (corresponding 1.8 x 107 cells/ml), 96% of patulin was degraded (initial contamination of 4.5 µg/ml of patulin) after 143 hours of incubation at 25 °C under static conditions. However, 90% degradation occurred when the juice was contaminated with 7.0 µg/ml under the same conditions, indicating that the biodegradation rate is concentrationdependent. The effective biodegradation of patulin using P. ohmeri 158 and S. cerevisiae demonstrates a promising application for innocuous yeast isolated from natural microbiota in the biological control, which can prevent both fruit spoilage and P. expansum mycotoxin contamination.