A unitary model for structure functions and diffractive production at small x

We propose a unified approach which describes both structure functions in the small-$x$ region and diffractive production in $\gamma^*p$-interactions. It is shown that the model, based on reggeon calculus and a quark-parton picture of the interaction, gives a good description of available experimental data in a broad region of $Q^2$ (including $Q^2 =0$) with a single Pomeron of intercept $\alpha_P(0) = 1.2$. Predictions for very small $x$ are given and the problem of saturation of parton densities is discussed.Comment: 43 pages, latex, 15 postscript figure

Prevalencia de obesidad y otros factores de riesgo cardiovascular en una población rural del Paraguay(1)

OBJETIVO: Determinar la prevalencia de obesidady su relación con otros factores de riesgo cardiovasculares(FRC): antecedente familiar, HTA, DM, Dislipemia; enuna población rural del Paraguay.MATERIAL Y METODO: estudio observacional,descriptivo con componente analítico, de residentes enBella Vista Norte, realizado de enero a marzo de 2004.Muestreo aleatorio simple con visitas casa por casa, fueronincluidos individuos de 15 a 60 años de ambos sexos.Las variables fueron: peso, talla, IMC, circunferencia decintura y factores de riesgo cardiovasculares. Se analizó laasociación existente entre obesidad y otros FRC mediantela prueba chi2, se tomó la razón de riesgo (RR) y los valoresde p para el análisis de los resultados.RESULTADOS: de los 216 sujetos evaluados, 140(64,8%) eran de sexo femenino, con una media de edad:40±13 años. Se encontró sobrepeso/obesidad en 52,3%,(33,8% con sobrepeso y 18,5% obesos), en 44/76 (57,9%)varones y en 69/140 (49,6%). La mayor tasa de sobrepesofue observada entre 45 y 55años (37%) y obesidad entre35 y 54 años (63%). Los antecedentes familiares de losque presentaban sobrepeso/obesidad es la siguiente: HTA:52,2%, Dislipidemia 40,7%, DM 30,1%, ACV 9,7% eIAM 8,8%. Hubo asociación entre sobrepeso/obesidadcon: Dislipidemia en 59% (RR=2,11; IC95% 1,5–3;p<10!5); con HTA en 52,2% (RR=2,34; IC95% 1,6–3;p<10–5); con tolerancia anormal a la glucosa un 7,1%(RR=3,65; IC95% 0,8–16,8; p=NS). Se encontró obesidadabdominal en 63 (29,2%). Estos presentaron asociacióncon HTA en el 54% (RR=1,72; IC95%1,24-2,4; p<10!2),con dislipidemia 65,1% (RR=1,8; IC95% 1,4–2,4; p<10–4); con DM en 9,5% (RR=3,64; IC95% 1,06-12,4; p=NS).Hubo correlación lineal estadísticamente significativaentre los valores de IMC con los de: la presión arterial(estad f=24, r2=0,10, p<10Ñ6), con los del colesterol (estadf=19, r2=0,08, p<10Ñ6), y los de triglicéridos (estad f=16,r2=0,07, p<10Ñ4); y entre los valores de cintura con losde: presión arterial (estad f=30, r2=0,12, p<10Ñ6), con losdel colesterol (estad f=24, r2=0,10, p<10Ñ3), y los de triglicéridos(estad f=33, r2=0,14, p<10Ñ3). Las asociacionesmostraron además ser estadísticamente significativas conlos test de comparación de medias.CONCLUSIÓN: Poco más de la mitad de la poblaciónrural estudiada presentó sobrepeso/obesidad, asociándoseéste parámetro con la hipertensión arterial y la dislipidemiaen forma estadísticamente significativa

Maternal high fat diet compromises survival and modulates lung development of offspring, and impairs lung function of dams (female mice)

© 2019 The Author(s). Published in Respiratory Research. Background: Epidemiological studies have identified strong relationships between maternal obesity and offspring respiratory dysfunction; however, the causal direction is not known. We tested whether maternal obesity alters respiratory function of offspring in early life. Methods: Female C57Bl/6 J mice were fed a high or low fat diet prior to and during two rounds of mating and resulting pregnancies with offspring lung function assessed at 2 weeks of age. The lung function of dams was measured at 33 weeks of age. Results: A high fat diet caused significant weight gain prior to conception with dams exhibiting elevated fasting glucose, and glucose intolerance. The number of surviving litters was significantly less for dams fed a high fat diet, and surviving offspring weighed more, were longer and had larger lung volumes than those born to dams fed a low fat diet. The larger lung volumes significantly correlated in a linear fashion with body length. Pups born from the second pregnancy had reduced tissue elastance compared to pups born from the first pregnancy, regardless of the dam's diet. As there was reduced offspring survival born to dams fed a high fat diet, the statistical power of lung function measures of offspring was limited. There were signs of increased inflammation in the bronchoalveolar lavage fluid of dams (but not offspring) fed a high fat diet, with more tumour necrosis factor-α, interleukin(IL)-5, IL-33 and leptin detected. Dams that were fed a high fat diet and became pregnant twice had reduced fasting glucose immediately prior to the second mating, and lower levels of IL-33 and leptin in bronchoalveolar lavage fluid. Conclusions: While maternal high fat diet compromised litter survival, it also promoted somatic and lung growth (increased lung volume) in the offspring. Further studies are required to examine downstream effects of this enhanced lung volume on respiratory function in disease settings

TDP-43 induces p53-mediated cell death of cortical progenitors and immature neurons

TAR DNA-binding protein 43 (TDP-43) is a key player in neurodegenerative diseases including frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). Accumulation of TDP-43 is associated with neuronal death in the brain. How increased and disease-causing mutant forms of TDP-43 induce cell death remains unclear. Here we addressed the role of TDP-43 during neural development and show that reduced TDP-43 causes defects in neural stem/progenitor cell proliferation but not cell death. However, overexpression of wild type and TDP-43A315T proteins induce p53-dependent apoptosis of neural stem/progenitors and human induced pluripotent cell (iPS)-derived immature cortical neurons. We show that TDP-43 induces expression of the proapoptotic BH3-only genes Bbc3 and Bax, and that p53 inhibition rescues TDP-43 induced cell death of embryonic mouse, and human cortical neurons, including those derived from TDP-43G298S ALS patient iPS cells. Hence, an increase in wild type and mutant TDP-43 induces p53-dependent cell death in neural progenitors developing neurons and this can be rescued. These findings may have important implications for accumulated or mutant TDP-43 induced neurodegenerative diseases

Autonomous growth potential of leukemia blast cells is associated with poor prognosis in human acute leukemias

We have described a severe combined immunodeficiency (SCID) mouse model that permits the subcutaneous growth of primary human acute leukemia blast cells into a measurable subcutaneous nodule which may be followed by the development of disseminated disease. Utilizing the SCID mouse model, we examined the growth potential of leukemic blasts from 133 patients with acute leukemia, (67 acute lymphoblastic leukemia (ALL) and 66 acute myeloid leukemia (AML)) in the animals after subcutaneous inoculation without conditioning treatment. The blasts displayed three distinct growth patterns: "aggressive", "indolent", or "no tumor growth". Out of 133 leukemias, 45 (33.8%) displayed an aggressive growth pattern, 14 (10.5%) displayed an indolent growth pattern and 74 (55.6%) did not grow in SCID mice. The growth probability of leukemias from relapsed and/or refractory disease was nearly 3 fold higher than that from patients with newly diagnosed disease. Serial observations found that leukemic blasts from the same individual, which did not initiate tumor growth at initial presentation and/or at early relapse, may engraft and grow in the later stages of disease, suggesting that the ability of leukemia cells for engraftment and proliferation was gradually acquired following the process of leukemia progression. Nine autonomous growing leukemia cell lines were established in vitro. These displayed an aggressive proliferation pattern, suggesting a possible correlation between the capacity of human leukemia cells for autonomous proliferation in vitro and an aggressive growth potential in SCID mice. In addition, we demonstrated that patients whose leukemic blasts displayed an aggressive growth and dissemination pattern in SClD mice had a poor clinical outcome in patients with ALL as well as AML. Patients whose leukemic blasts grew indolently or whose leukemia cells failed to induce growth had a significantly longer DFS and more favorable clinical course

Thermoplastic cassava starch-chitosan bilayer films containing essential oils

[EN] Starch-chitosan bilayer films, containing or not essential oils in the casted chitosan layer were obtained by thermo-compression. Bilayer films exhibited a good interfacial adhesion and better mechanical resistance than starch monolayers, although they were less stretchable and less transparent. Starchchitosan films were effective at controlling the bacterial growth in pork meat, but the thermal treatment applied to obtain the bilayers reduced their antimicrobial properties as compared to chitosan monolayers. The addition of essential oils did not promote any antimicrobial action in chitosan mono and bilayer films applied to pork meat. The final amount of essential oils in the films was very limited probably due to the losses occurred during film processing method. Other strategies to incorporate the essential oils into chitosan-based films should be used to improve their final retention in the film matrix and their effective release into the coated food. (C) 2017 Elsevier Ltd. All rights reserved.The authors acknowledge the financial support provided by the Spanish Ministerio de Economia y Competividad (Projects AGL2013-42989-R and AGL2016-76699-R). Author Cristina Valencia-Sullca thanks the Peruvian Grant National Program (PRONABEC).Valencia-Sullca, CE.; Vargas, M.; Atarés Huerta, LM.; Chiralt, A. (2018). Thermoplastic cassava starch-chitosan bilayer films containing essential oils. Food Hydrocolloids. 75:107-115. https://doi.org/10.1016/j.foodhyd.2017.09.008S1071157

Non-Metabolic Membrane Tubulation and Permeability Induced by Bioactive Peptides

BACKGROUND: Basic cell-penetrating peptides are potential vectors for therapeutic molecules and display antimicrobial activity. The peptide-membrane contact is the first step of the sequential processes leading to peptide internalization and cell activity. However, the molecular mechanisms involved in peptide-membrane interaction are not well understood and are frequently controversial. Herein, we compared the membrane activities of six basic peptides with different size, charge density and amphipaticity: Two cell-penetrating peptides (penetratin and R9), three amphipathic peptides and the neuromodulator substance P. METHODOLOGY/PRINCIPAL FINDINGS: Experiments of X ray diffraction, video-microscopy of giant vesicles, fluorescence spectroscopy, turbidimetry and calcein leakage from large vesicles are reported. Permeability and toxicity experiments were performed on cultured cells. The peptides showed differences in bilayer thickness perturbations, vesicles aggregation and local bending properties which form lipidic tubular structures. These structures invade the vesicle lumen in the absence of exogenous energy. CONCLUSIONS/SIGNIFICANCE: We showed that the degree of membrane permeabilization with amphipathic peptides is dependent on both peptide size and hydrophobic nature of the residues. We propose a model for peptide-induced membrane perturbations that explains the differences in peptide membrane activities and suggests the existence of a facilitated “physical endocytosis,” which represents a new pathway for peptide cellular internalization

Genetic diversity of the African malaria vector Anopheles gambiae

The sustainability of malaria control in Africa is threatened by the rise of insecticide resistance in Anopheles mosquitoes, which transmit the disease1. To gain a deeper understanding of how mosquito populations are evolving, here we sequenced the genomes of 765 specimens of Anopheles gambiae and Anopheles coluzzii sampled from 15 locations across Africa, and identified over 50 million single nucleotide polymorphisms within the accessible genome. These data revealed complex population structure and patterns of gene flow, with evidence of ancient expansions, recent bottlenecks, and local variation in effective population size. Strong signals of recent selection were observed in insecticide-resistance genes, with several sweeps spreading over large geographical distances and between species. The design of new tools for mosquito control using gene-drive systems will need to take account of high levels of genetic diversity in natural mosquito populations