Modulation of intracellular pH in human ovarian cancer

To sustain tumor growth, the cancer cells need to adapt to low levels of oxygen (i.e., hypoxia) in the tumor tissue and to the tumor-associated acidic microenvironment. In this phenomenon, the activation of the sodium/proton exchanger 1 (NHE1) at the plasma membrane and the hypoxia-inducible factor (HIF) are critical for the control of the intracellular pH (pHi) and for hypoxia adaptation, respectively. Interestingly, both of these mechanisms end in sustaining cancer cell proliferation. However, regulatory mechanisms of pHi in human ovary tissue and in malignant ascites are unknown. Additionally, a potential role of NHE1 in the modulation of H(+) efflux in human ovarian cancer cells is unknown. In this review, we discussed the characteristics of tumor microenvironment of primary human ovarian tumors and tumor ascites, in terms of pHi regulatory mechanisms and oxygen level. The findings described in the literature suggest that NHE1 may likely play a role in pHi regulation and cell proliferation in human ovarian cancer, potentially involving HIF2α activation. Since ovarian cancer is the fifth cause of prevalence of women cancer in Chile and is usually of late diagnosis, i.e., when the disease jeopardizes peritoneal cavity and other organs, resulting in reduced patient survival, new efforts are required to improve patient-life span and for a better understanding of the pathophysiology of the disease. The potential advantage of the use of amiloride and amiloride-derivatives for cancer treatment in terms of NHE1 expression and activity is also discussed as a therapeutic approach in human ovarian cancer.

Cerebral Hemodynamics Patterns by Transcranial Doppler in Patients With Acute Liver Failure

INTRODUCTION

About half of patients with acute liver failure (ALF) show clinical signs of cerebral edema and intracranial hypertension. Neuroimaging diagnostics and electroencephalography have poor correlation with intracranial pressure measurement.

OBJECTIVE

The objective of this study was to characterize the cerebral hemodynamics patterns with transcranial Doppler (TCD) sonography in patients with ALF.

METHOD

We studied 21 patients diagnosed with ALF, admitted to the intensive care unit (ICU) at the Centro de Investigaciones Médico Quirúrgicas of Cuba. All of these patients had a TCD performed on arrival at ICU, evaluating the following: systolic (SV), diastolic (DV), and medium (MV) flows velocities and pulsatility index (PI) in right middle cerebral artery (RMCA) via temporal windows.

RESULTS

The sonographic patterns of cerebral hemodynamics were as follows: low-flow, 12 patients (57.1%); high resistance, 5 patients (23.8%); and hyperemic, 4 patients (19%). Patients who died while waiting had lower MV RMCA (56.1 vs 58.1 cm/s) and higher PI (1.71 vs 1.41) than patients who could undergo transplantation (P = .800 and P = .787, respectively).

CONCLUSIONS

In patients diagnosed with ALF admitted to the ICU the predominating cerebral hemodynamic pattern was low-flow with resistance increase. The TCD was shown to be a useful tool in the initial evaluation for prognosis and treatment.

Insulin receptor isoforms: an integrated view focused on gestational diabetes mellitus

The human insulin receptor (IR) exists in two isoforms that differ by the absence (IR-A) or the presence (IR-B) of a 12-amino acid segment encoded by exon 11. Both isoforms are functionally distinct regarding their binding affinities and intracellular signalling. However, the underlying mechanisms related to their cellular functions in several tissues are only partially understood. In this review, we summarize the current knowledge in this field regarding the alternative splicing of IR isoform, tissue-specific distribution and signalling both in physiology and disease, with an emphasis on the human placenta in gestational diabetes mellitus (GDM). Furthermore, we discuss the clinical relevance of IR isoforms highlighted by findings that show altered insulin signalling due to differential IR-A and IR-B expression in human placental endothelium in GDM pregnancies. Future research and clinical studies focused on the role of IR isoform signalling might provide novel therapeutic targets for treating GDM to improve the adverse maternal and neonatal outcomes.

On-water remote monitoring robotic system for estimating the patch coverage of Anabaena sp. filaments in shallow water

An on-water remote monitoring robotic system was developed for indirectly estimating the relative density of marine cyanobacteria blooms at the subtidal sandy-rocky beach in Balandra Cove, Baja California Sur, Mexico. The system is based on an unmanned surface vehicle to gather underwater videos of the seafloor for avoiding physical damage on Anabaena sp. cyanobacteria colonies, which grow in tufts of filaments weakly attached to rocks, seagrass, and macroalgae. An on-axis image stabilization mechanism was developed to support a camcorder and minimize wave perturbation while recording underwater digital images of the seafloor. Color image processing algorithms were applied to estimate the patch coverage area and density, since Anabaena sp. filaments exhibit a characteristic green tone. Results of field tests showed the feasibility of the robotic system to estimate the relative density, distribution, and coverage area of cyanobacteria blooms, preventing the possible impact of direct observation. The robotic system could also be used in surveys of other benthos in the sublittoral zone.

Regulation of lipid metabolism and peroxisome proliferator-activated receptors in rainbow trout adipose tissue by lipolytic and antilipolytic endocrine factors

The aim of this study was to determine the effects of growth hormone (GH) and insulin-like growth factor (IGF)-I on glycerol release and the regulation of IGF-I and IGF-II expression by GH in isolated rainbow trout adipocytes. Cells were also incubated with GH, tumor necrosis factor α (TNFα), or insulin to analyze the gene expression of peroxisome proliferator-activated receptors (PPARs) and lipid metabolism markers: hormone sensitive lipase, fatty acid synthase (FAS), and lipoprotein lipase. Complimentary in vivo experiments were performed by intraperitoneally administering insulin, TNFα, or lipopolysaccharide and subjecting the animals to fasting and refeeding periods. The results showed that IGF-I had an antilipolytic effect and GH had a lipolytic effect; the latter occurred independently of IGF modulation and in conjunction with a reduction in PPARα expression in adipocytes. The anabolic action of insulin was demonstrated through its upregulation of lipogenic genes such as lipoprotein lipase, FAS, and PPARγ, whereas GH, by contrast, inhibited FAS expression in adipose tissue. The gene transcription levels of PPARs changed differentially during fasting and refeeding, and the TNFα and/or lipopolysaccharide administration suggested that the regulation of PPARs helps maintain metabolic adipose tissue homeostasis in rainbow trout.

A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND

No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy.

METHODS

We used data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home.

RESULTS

As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001).

CONCLUSIONS

Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated.

Advances in artificial olfaction: sensors and applications

The artificial olfaction, based on electronic systems (electronic noses), includes three basic functions that operate on an odorant: a sample handler, an array of gas sensors, and a signal-processing method. The response of these artificial systems can be the identity of the odorant, an estimate concentration of the odorant, or characteristic properties of the odour as might be perceived by a human. These electronic noses are bio inspired instruments that mimic the sense of smell. The complexity of most odorants makes characterisation difficult with conventional analysis techniques, such as gas chromatography. Sensory analysis by a panel of experts is a costly process since it requires trained people who can work for only relatively short periods of time. The electronic noses are easy to build, provide short analysis times, in real time and on-line, and show high sensitivity and selectivity to the tested odorants. These systems are non-destructive techniques used to characterise odorants in diverse applications linked with the quality of life such as: control of foods, environmental quality, citizen security or clinical diagnostics. However, there is much research still to be done especially with regard to new materials and sensors technology, data processing, interpretation and validation of results. This work examines the main features of modern electronic noses and their most important applications in the environmental, and security fields. The above mentioned main components of an electronic nose (sample handling system, more advanced materials and methods for sensing, and data processing system) are described. Finally, some interesting remarks concerning the strengths and weaknesses of electronic noses in the different applications are also mentioned.

Optimization of the magnetoelectric response of poly(vinylidene fluoride)/epoxy/Vitrovac laminates

The effect of the bonding layer type and piezoelectric layer thickness on the magnetoelectric (ME) response of layered poly(vinylidene fluoride) (PVDF)/epoxy/Vitrovac composites is reported. Three distinct epoxy types were tested, commercially known as M-Bond, Devcon, and Stycast. The main differences among them are their different mechanical characteristics, in particular the value of the Young modulus, and the coupling with the polymer and Vitrovac (Fe39Ni39Mo4Si6B12) layers of the laminate. The laminated composites prepared with M-Bond epoxy exhibit the highest ME coupling. Experimental results also show that the ME response increases with increasing PVDF thickness, the highest ME response of 53 V·cm(-1)·Oe(-1) being obtained for a 110 μm thick PVDF/M-Bond epoxy/Vitrovac laminate. The behavior of the ME laminates with increasing temperatures up to 90 °C shows a decrease of more than 80% in the ME response of the laminate, explained by the deteriorated coupling between the different layers. A two-dimensional numerical model of the ME laminate composite based on the finite element method was used to evaluate the experimental results. A comparison between numerical and experimental data allows us to select the appropriate epoxy and to optimize the piezoelectric PVDF layer width to maximize the induced magnetoelectric voltage. The obtained results show the critical role of the bonding layer and piezoelectric layer thickness in the ME performance of laminate composites.

Insulin, IGF-I, and muscle MAPK pathway responses after sustained exercise and their contribution to growth and lipid metabolism regulation in gilthead sea bream

Herein, we studied whether sustained exercise positively affects growth of gilthead sea bream by alterations in a) plasma concentrations of insulin and IGF-I, b) signaling pathways in muscle, or c) regulation of lipid metabolism. Specifically, we evaluated the effects of moderated swimming (1.5 body lengths per second; BL/s) on the circulating concentrations of insulin and IGF-I, morphometric parameters, and expression of genes related to lipid metabolism in gilthead sea bream (80-90 g BW). Exercise increased the specific growth rate (P < 0.05) and reduced the hepatosomatic index (P = 0.006). Plasma IGF-I concentrations increased in exercised fish (P = 0.037), suggesting a role for this endocrine factor in the control of muscular growth and metabolic homeostasis during swimming. The observed decrease in plasma insulin concentrations (P = 0.016) could favor the mobilization of tissue reserves in exercised fish. In this sense, the increase in liver fatty acid content (P = 0.041) and the changes in expression of peroxisome proliferator-activated receptors PPARα (P = 0.017) and PPARγ (P = 0.033) indicated a hepatic lipid mobilization. Concentration of glycogen in both white and red muscles was decreased (P = 0.021 and P = 0.017, respectively) in exercised (n = 12) relative to control (n = 12) gilthead sea bream, whereas concentrations of glucose (P = 0.016) and lactate (P = 0.0007) were decreased only in red muscle, indicating the use of these substrates. No changes in the glucose transporter and in lipoprotein lipase mRNA expression were found in any of the tissues studied. Exercised sea bream had decreased content of PPARβ mRNA in white and red muscle relative to control sea bream expression (P = 0.001 and P = 0.049, respectively). Mitogen-activated protein kinase phosphorylation was significantly down-regulated in both white and red muscles of exercised sea bream (P = 0.0374 and P = 0.0371, respectively). Tumor necrosis factor-α expression of white muscle was down-regulated in exercised gilthead sea bream (P = 0.045). Collectively, these results contribute to the knowledge base about hormonal regulation of growth and lipid metabolism in exercised gilthead sea bream.

Composition and sensory evaluation of lamb carcasses used for the traditional Mexican lamb dish, "barbacoa"

The objective of this study was to determine the differences in carcass characteristics and sensory attributes of "barbacoa" (a traditional Mexican lamb dish), both of imported (New Zealand) and domestic lambs in Mexico. A total of 28 carcasses from Pelibuey, Pelibuey×Suffolk and imported lambs were used. Carcass composition was determined by dissection of primal cuts from the left half of each carcass. The "barbacoa" from each ovine group was prepared separately in order to perform a consumer sensory evaluation for aroma, taste and tenderness. Results showed that imported lambs had larger carcasses, greater fatness and had better conformation than national lambs. There was no difference between groups in terms of lean tissue percentage (muscle+others) or in total carcass fat. The sensory attributes of the "barbacoa" did not differ among breeds. Pelibuey lambs (rustic, prolific and adaptable to the wide variety of Mexican climates) show competitive production performance in relation to specialized breeds.

Characterization and endocrine regulation of proliferation and differentiation of primary cultured preadipocytes from gilthead sea bream (Sparus aurata)

A preadipocyte primary cell culture was established to gain knowledge about adipose tissue development in gilthead sea bream (Sparus aurata), one of the most extensively produced marine aquaculture species in the Mediterranean. The preadipocytes obtained from the stromal-vascular cell fraction of adipose tissue proliferated in culture, reaching confluence around day 8. At that time, the addition of an adipogenic medium promoted differentiation of the cells into mature adipocytes, which showed an enlarged cytoplasm filled with lipid droplets. First, cell proliferation and differentiation were analyzed under control and adipogenic conditions during culture development. Next, the effects of insulin, GH, and IGF-I on cell proliferation were evaluated at day 8. All peptides significantly stimulated proliferation of the cells after 48 h of incubation (P < 0.002 for GH and IGF-I and P < 0.05 for insulin), despite no differences were observed between the different doses tested. Subsequently, the effects of insulin and IGF-I maintaining differentiation when added to growth medium were studied at day 11, after 3 d of induction with adipogenic medium. The results showed that IGF-I is more potent than insulin enhancing differentiation (P < 0.01 for IGF-I compared with the control). In summary, a primary culture of gilthead sea bream preadipocytes has been characterized and the effects of several regulators of growth and development have been evaluated. This cellular system can be a good model to study the process of adipogenesis in fish, which may help improve the quality of the product in aquaculture.

Effect of guar gum on glucose and lipid metabolism in white sea bream Diplodus sargus

The aim of this study was to assess the role of soluble non-starch polysaccharide (guar gum) on white sea bream Diplodus sargus, glucose and lipid metabolism. A control diet was formulated to contain 40 % crude protein, 14 % crude lipids and 35 % pregelatinized maize starch, and three other diets were formulated similar to the control diet except for guar gum, which was included at 4 % (diet GG4), 8 % (diet GG8) or 12 % (diet GG12). Diets were fed to the fish for 9 weeks on a pair-feeding scheme. Guar gum had no effect on growth performance, feed efficiency, glycaemia, cholesterolaemia and plasma triacylglyceride levels. Hepatic glucokinase and pyruvate kinase activities, liver glycogen content and liver insulin-like growth factor-I gene expression were not affected by dietary guar gum, while fructose-1,6-bisphosphatase activity was lower in fish fed guar gum-supplemented diets. Hepatic glucose-6-phosphate dehydrogenase activity was higher in fish fed diets GG4 and GG8 than in the control group. Overall, data suggest that in contrast to mammals guar gum had no effect on white sea bream glucose utilization and in lowering plasma cholesterol and triacylglyceride levels. However, it seems to contribute to lower endogenous glucose production.

Overall survival benefit for sequential doxorubicin-docetaxel compared with concurrent doxorubicin and docetaxel in node-positive breast cancer--8-year results of the Breast International Group 02-98 phase III trial

Background In women with node-positive breast cancer, the Breast International Group (BIG) 02-98 tested the incorporation of docetaxel (Taxotere) into doxorubicin (Adriamycin)-based chemotherapy, and compared sequential and concurrent docetaxel. At 5 years, there was a trend for improved disease-free survival (DFS) with docetaxel. We present results at 8-year median follow-up and exploratory analyses within biologically defined subtypes. Methods Patients were randomly assigned to one of four treatments: (i) sequential control: doxorubicin (A) (75 mg/m(2)) × 4 →classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF); (ii) concurrent control: doxorubicin, cyclophosphamide (AC)(60/600 mg/m(2)) × 4 →CMF; (iii) sequential docetaxel: A (75 mg/m(2)) × 3 → docetaxel (T) (100 mg/m(2)) × 3 → CMF and (iv) concurrent docetaxel: AT(50/75 mg/m(2)) × 4 →CMF. The primary comparison evaluated docetaxel efficacy regardless of the schedule. Exploratory analyses were undertaken within biologically defined subtypes. Results Two thousand eight hundred and eighty-seven patients were enrolled. After 93.4 months of median follow-up, there were 916 DFS events. For the primary comparison, there was no significant improvement in DFS from docetaxel [hazard ratio (HR) = 0.91, 95% confidence interval (CI) = 0.80-1.05, P = 0.187]. In secondary comparisons, sequential docetaxel significantly improved DFS compared with sequential control (HR = 0.81, 95% CI = 0.67-0.99, P = 0.036), and significantly improved DFS (HR = 0.84, 95% CI = 0.72-0.99, P = 0.035) and overall survival (OS) (HR = 0.79, 95% CI = 0.65-0.98, P = 0.028) compared with concurrent doxorubicin-docetaxel. Luminal-A disease had the best prognosis. HRs favored addition of sequential docetaxel in all subtypes, except luminal-A; but this observation was not statistically supported because of limited numbers. Conclusion With further follow-up, the sequential docetaxel schedule resulted in significantly better OS than concurrent doxorubicin-docetaxel, and continued to show better DFS than sequential doxorubicin-based control.

Electronic nose for the identification of pig feeding and ripening time in Iberian hams

An electronic nose system to control the processing of dry-cured Iberian ham is presented. The sensors involved are tin oxide semiconductors thin films. They were prepared by RF sputtering. Some of the sensors were doped with metal catalysts as Pt and Pd, in order to improve the selectivity of the sensors. The multisensor with 16 semiconductor sensors, gave different responses from two types of dry-cured Iberian hams which differ in the feeding and curing time. The data has been analysed using the PCA (principal component analysis) and backpropagation and probabilistic neural networks. The analysis shows that different types of Iberian ham can be discriminated and identified successfully.

Influence of temperature on structure and magnetic properties of exchange coupled TbCo/FeNi bilayers

Among amorphous films of rare earth-transition metal (RE-TM) alloys as exchange-biasing layers in magnetoresistive heads and spin-valve sensors, the amorphous Tb-Co films have most high practical potential. In the present work the influence of the temperature and the heat treatment parameters on the structure and magnetic properties was studied for exchange bias FeNi/Tb35Co65 bilayers annealed in vacuum or a nitrogen flow. A simple explanation of the dependence of the magnetic properties on the temperature and the heat treatment parameters connected with structural changes in each one of the layers was proposed.

Glycemic and insulin responses in white sea bream Diplodus sargus, after intraperitoneal administration of glucose

A glucose tolerance test was performed in white sea bream Diplodus sargus, juveniles to evaluate the effect of a glucose load on plasma glucose, insulin, triacylglyceride levels, and on liver glycogen storage in order to study the capability of glucose utilization by this species. After being fasted for 48 h, fish were intraperitoneally injected with either 1 g of glucose per kg body weight or a saline solution. Plasma glucose rose from a basal level of 4 to a peak of 18-19 mmol l(-1), 2-4 h after glucose injection and fish exhibited hyperglycemia for 9 h. An insulin peak (from 0.5 to 0.8 ng ml(-1)) was observed 2-6 h after glucose injection, and basal value was attained within 9 h. Liver glycogen peaked 6-12 h after the glucose load and thereafter decreased to the basal value which was attained 24 h after injection. Plasma triacylglycerides in glucose-injected fish were only significantly higher than the basal value 12 h after injection. Glucose-injected fish generally showed lower plasma triacylglyceride levels than control fish. Our results indicate that under these experimental conditions, glucose acts as an insulin secretagogue in white sea bream juveniles. Moreover, insulin may have contributed to restoring basal plasma glucose levels by enhancing glucose uptake in the liver. Further studies are needed to corroborate the lipolytic action of glucose. Clearance of glucose from the blood stream was fast, comparatively to other species, indicating that white sea bream has a good capability of glucose utilization.

Nanoscale strain-induced pair suppression as a vortex-pinning mechanism in high-temperature superconductors

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centres in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa(2)Cu(3)O(7) matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.