Compaction and condensation of DNA mediated by the C-terminal domain of Hfq.

Hfq is a bacterial protein that is involved in several aspects of nucleic acids metabolism. It has been described as one of the nucleoid associated proteins shaping the bacterial chromosome, although it is better known to influence translation and turnover of cellular RNAs. Here, we explore the role of Escherichia coli Hfq's C-terminal domain in the compaction of double stranded DNA. Various experimental methodologies, including fluorescence microscopy imaging of single DNA molecules confined inside nanofluidic channels, atomic force microscopy, isothermal titration microcalorimetry and electrophoretic mobility assays have been used to follow the assembly of the C-terminal and N-terminal regions of Hfq on DNA. Results highlight the role of Hfq's C-terminal arms in DNA binding, change in mechanical properties of the double helix and compaction of DNA into a condensed form. The propensity for bridging and compaction of DNA by the C-terminal domain might be related to aggregation of bound protein and may have implications for protein binding related gene regulation.

Energy footprint and carbon emission reduction using off-the-grid solar-powered mixing for lagoon treatment.

Mixing is the driver for the energy footprint of water resource recovery in lagoons. With the availability of solar-powered equipment, one potential measure to decrease the environmental impacts of treatment is to transition to an off-the-grid treatment. We studied the comparative scenarios of an existing grid-powered mixer and a solar-powered mixer. Testing was conducted to monitor the water quality, and to guarantee that the effluent concentrations were maintained equally between the two scenarios. Meanwhile, the energy consumption was recorded with the electrical energy monitor by the wastewater treatment utility, and the carbon emission changes were calculated using the emission intensity of the power utility. The results show that after the replacement, both energy usage and energy costs were significantly reduced, with the energy usage having decreased by 70% and its cost by 47%. Additionally, carbon-equivalent emission from electricity importation dropped by 64%, with an effect on the overall carbon emissions (i.e., including all other contributions from the process) decreasing from 3.8% to 1.5%.

Impact of Macroporosity on Catalytic Upgrading of Fast Pyrolysis Bio-Oil by Esterification over Silica Sulfonic Acids.

Fast pyrolysis bio-oils possess unfavorable physicochemical properties and poor stability, in large part, owing to the presence of carboxylic acids, which hinders their use as biofuels. Catalytic esterification offers an atom- and energy-efficient route to upgrade pyrolysis bio-oils. Propyl sulfonic acid (PrSO3 H) silicas are active for carboxylic acid esterification but suffer mass-transport limitations for bulky substrates. The incorporation of macropores (200 nm) enhances the activity of mesoporous SBA-15 architectures (post-functionalized by hydrothermal saline-promoted grafting) for the esterification of linear carboxylic acids, with the magnitude of the turnover frequency (TOF) enhancement increasing with carboxylic acid chain length from 5 % (C3 ) to 110 % (C12 ). Macroporous-mesoporous PrSO3 H/SBA-15 also provides a two-fold TOF enhancement over its mesoporous analogue for the esterification of a real, thermal fast-pyrolysis bio-oil derived from woodchips. The total acid number was reduced by 57 %, as determined by GC×GC-time-of-flight mass spectrometry (GC×GC-ToFMS), which indicated ester and ether formation accompanying the loss of acid, phenolic, aldehyde, and ketone components.

Conocimientos, actitudes y prácticas sobre la prueba de citología cervical en una población rural peruana / Knowledge, attitudes and practices on cervical cytology in a Peruvian rural population

Introducción: La citología cervical constituye la principal herramienta para la detección y tratamiento del cáncer de cérvix. Algunos estudios llevados a cabo en población urbana han relacionado la realización y adherencia con los conocimientos, las actitudes y las prácticas favorables de las mujeres con respecto a esta prueba. Objetivo: evaluar los conocimientos, actitudes y prácticas con respecto a la citología cervical en mujeres pertenecientes a un grupo poblacional del ámbito rural. Material y Métodos: estudio de corte transversal-analítico en una población de aproximadamente 3148 mujeres en edad fértil, de ellas se obtuvo una muestra representativa. Se utilizó una encuesta anónima, validada, dirigida, y aplicada por personal de salud capacitado que labora en centros de salud del primer nivel de atención de los distritos de la provincia de Bolívar, La Libertad. Resultados: El 80 por ciento de las mujeres encuestadas tuvo un nivel de conocimiento alto e intermedio, el 70 por ciento una actitud favorable, mientras que el 44 por ciento reportó prácticas correctas en relación con la prueba de citología cervical. El nivel de conocimiento alto e intermedio estuvo asociado a la edad mayor de 30 años (p:0.02), estado civil casada (p:0.05), el mayor grado de instrucción (p:0.00) y el uso de métodos anticonceptivos (p:0.01); no se encontró relación con la edad de inicio de relaciones sexuales (p:0.98). Conclusiones: Existe un alto nivel de conocimientos, actitudes y prácticas correctas hacia la citología cervical en la población rural de la provincia de Bolívar, pero una baja adherencia hacia la misma(AU)

Introduction: Cervical cytology is the main tool for the detection and treatment of cervical cancer. Some studies carried out in the urban population have associated the realization and adherence with knowledge, attitudes and favorable practices of women with respect to this test. Objective: The aim of this study was to determine the level of knowledge, attitudes and practices towards cervical cytology in women of childbearing age in a rural Peruvian province. Material and Methods: A cross-sectional analytical study was conducted in a population of approximately 3148 women of childbearing age, a representative sample was obtained. An anonymous, validated, directed survey was used; it was applied by trained health personnel working in health centers of the primary care level in the districts of the province of Bolívar, La Libertad. Results: A total of 400 surveys were carried out. The results showed that 80 percent of the women surveyed had high and intermediate levels of knowledge, 70 percent had a favorable attitude, while 44 percent reported correct practices related to the cervical cytology test. The high and intermediate levels of knowledge were associated with age over 30 years (p: 0.02), married marital status (p: 0.05), the highest level of instruction (p: 0.00) and the use of contraceptive methods (p: 0.01); no relationship was found with the age of onset of sexual intercourse (p: 0.98). Conclusions: There is a high level of knowledge, attitudes and correct practices towards cervical cytology in the rural population of the province of Bolívar, but a low adherence to it(AU)

Silica nanoparticles induce oxidative stress and inflammation of human peripheral blood mononuclear cells.

In the present study, the effects of 10- or 100-nm silica oxide (SiO2) NPs on human peripheral blood mononuclear cells (PBMC) were examined. Cytotoxic effects and oxidative stress effects, including glutathione (GSH) depletion, the formation of protein radical species, and pro-inflammatory cytokine responses, were measured. PBMC exposed to 10-nm NP concentrations from 50 to 4,000 ppm showed concentration-response increases in cell death; whereas, for 100-nm NPs, PBMC viability was not lost at <500 ppm. Interestingly, 10-nm NPs were more cytotoxic and induced more oxidative stress than 100-nm NPs. Immunoelectron micrographs show the cellular distribution of GSH and NPs. As expected based on the viability data, the 10-nm NPs disturbed cell morphology to a greater extent than did the 100-nm NPs. Antibody to the radical scavenger, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), was used for Western blot analysis of proteins with radicals; more DMPO proteins were found after exposure to 10-nm NPs than 100-nm NPs. Examination of cytokines (TNF-α, IL-1ra, IL-6, IL-8, IL-1ß, and IFN-γ) indicated that different ratios of cytokines were expressed and released after exposure to 10- and 100-nm NPs. IL-1ß production was enhanced by 10- and 100-nm NPs;, the cytotoxicity of the NPs was associated with an increase in the IL-1ß/IL-6 ratio and 100-nm NPs at concentrations that did not induce loss of cell viability enhanced IL-1ß and IL-6 to an extent similar to phytohemagglutinin (PHA), a T cell mitogen. In conclusion, our results indicate that SiO2 NPs trigger a cytokine inflammatory response and induce oxidative stress in vitro, and NPs of the same chemistry, but of different sizes, demonstrate differences in their intracellular distribution and immunomodulatory properties, especially with regard to IL-1ß and IL-6 expression.

The maternal autoimmune environment affects the social behavior of offspring.

Autism spectrum disorders (ASD) are neurodevelopmental disorders with unknown etiology. BTBR-T(+)tf/J (BTBR) mice, a mouse strain with behaviors that resemble autism and with elevated levels of anti-brain antibodies (Abs), have enhanced activation of peripheral B cells and CD4(+) T cells and an expanded percentage of CD4(+) T cells expressing Vß6 chains. The CD4(+)CD25(+)Vß6(+) and Vß6-splenic cells of BTBR mice have elevated levels of IL-4, IFN-γ and IL-17, but there appears to be no preferential CD4(+) T subset skewing/polarization. The high level of IgG production by BTBR B cells was dependent on T cells from BTBR mice. The CD4(+) T cells of BTBR mice, especially those expressing Vß6 become spontaneously activated and expanded in an autoimmune-like manner, which occurred in both BTBR and B6 hosts that received an equal number of BTBR and B6 bone marrow cells. BTBR mice also have an elevated percentage of peripheral blood neutrophils, which may represent their elevated inflammatory state. B6 offspring derived from B6 dams that were gestationally injected with purified IgG from sera of BTBR mice, but not IgG of B6 mice, developed significantly impaired social behavior. Additionally, B6 offspring that developed in BTBR dams had impaired social behavior, while BTBR offspring that developed in B6 dams had improved social behavior. All of the immunological and behavioral parameters of BTBR mice were compared with those of B6 mice, which have relatively normal behaviors. The results indicate maternal Abs and possibly other maternal influences affect the social behavior of offspring.

Immunomodulatory Effects of Danshen (Salvia miltiorrhiza) in BALB/c Mice.

Danshen, the root and rhizome of Salvia miltiorrhiza Bge, a Traditional Chinese Medicine, especially for cardiovascular and cerebrovascular diseases, has unique immunomodulatory effects. Danshen is capable of anti-inflammation and antiallergy, which are immunosuppressive activities, whereas it is also able to promote immunity against cancer, viruses, and bacteria. Most previous reports were performed with use of a purified compound or compounds of Danshen. Since there are more than twenty active compounds in Danshen, it is very difficult to predict that one compound will act the same way when it is combined with other compounds. In order to overcome this limitation, we used the crude form of Danshen to study its immunomodulatory effects in a mouse model. The mice were fed daily diet supplements of Danshen for three months and then tested for their immunity, including leukocyte subsets in peripheral blood, humoral and cell-mediated immune responses, and host defenses against a Listeria monocytogenes (LM) infection. Different doses of Danshen caused different immunomodulatory effects. Danshen at 0.5% decreased serum IgE production in BALB/c mice; 1% Danshen promoted cell-mediated immunity; Danshen at 0.5 and 1% inhibited the production of oxygen free radicals in liver and spleen and NO production in liver; 2% Danshen enhanced the host resistance against LM with increased numbers of peripheral monocytes and natural killer (NK) cells and decreased production of IL-1 ß and NO.

Shamrock surfactants with terminal carboxylate headgroups and a central phosphorodithioate or quaternary ammonium headgroup.

Surfactants 3 (tripotassium O,O'-di-[11-(carboxylato)undecyl]phosphorodithioate) and 4 (sodium 12-[dimethyl-(11-carboxylatoundecyl)ammonio]dodecanoate), which are new shamrock surfactants, were prepared and characterized. Shamrock surfactants represent a novel class of surfactants that contain a central headgroup connected to two flanking headgroups by hydrocarbon chains; they do not contain long-chain alkyl groups. Surfactants 3 and 4 were characterized in water by measurement of their Krafft temperatures and critical aggregation concentrations, and their aggregates were studied by 1H and 31P NMR spectroscopy, dynamic laser light scattering, and phase-contrast optical microscopy. Aqueous 3 and 4 were also studied by cryoetch high-resolution scanning electron microscopy, which revealed fences with interposed lacelike patterns for the former and compartments formed by irregular fences for the latter. Coacervates were likely formed upon the undisturbed hydration of 3 and 4, as determined by phase-contrast optical microscopy.

Surfactant quaternary ammonium hydrotris(1-pyrazolyl)borates.

Quaternary ammonium surfactants with the hydrotris(1-pyrazolyl)borate anion as an unusual counterion were prepared and characterized. Dodecyl- (1a), tetradecyl- (1b), and hexadecyltrimethylammonium hydrotris(1-pyrazolyl)borate (1c), as well as didodecyldimethylammonium hydrotris(1-pyrazolyl)borate (2), were prepared by metathesis reactions with the corresponding quaternary ammonium bromides and potassium hydrotris(1-pyrazolyl)borate (4). Although the surfactants have limited stabilities in water at 23 degrees C, they were characterized by measurement of their Krafft temperatures and critical aggregation concentrations. (1)H NMR spectroscopy suggested that the single-chain surfactants 1 form small aggregates in water and revealed an association of the quaternary ammonium and hydrotris(1-pyrazolyl)borate ions above their critical aggregation concentrations. Cryo-etch high-resolution scanning electron microscopy indicated that 1a and 1b most likely form segregation patterns upon plunge-freezing and cryo-etching of their aqueous solutions, and a single-crystal X-ray diffraction study of 1a was performed.

Tratamiento quirurgico de la esofagitis peptica / Peptical esophagitis surgical treatment

En 132 pacientes se empleo la tecnica de gastropexia posterior con calibracion del cardias, descrita originalmente por Hill en 1967. Los resultados fueron excelentes en 90 casos, de los 97 que puedieron ser controlados. Se considera que la existencia de epitelio columnar como revestimiento del extremo inferior del esofago, es una indicacion absoluta de cirugia, y que las estenosis severas que se presentan en estos otros pacientes, deben tratarse con dialataciones post-operatorias y que no tiene mayor objeto efectuarlas con anterioridad. Solamente el 50% de pacientes con estrecheces tratados en esta forma requirieron dilataciones post-operatorias. Hubo tres casos de mortalidad, pero solamente dos estuvieron relacionadas con la operacion

Tratamiento de las estenosis esofagicas pepticas / Treatment of peptic esophageal stenosis

El tratamiento de los pacientes con estenosis esofagica peptica es controvertido. La literatura medica contiene multiples informes que abogan por el manejo medico, con base en dilataciones esofagicas frecuentes (1,2). Sin embargo, muchos cirujanos consideran que estos pacientes presentan un reflujo gastroesofagico importante y que requieren una correccion quirurgica del mecanismo esfinteriano en el nivel del esofago distal complementada con la dilatacion transendoscopica de la estenosis durante el acto quirurgico, en casos severos (3,4). Proponemos la utilizacion rutinaria de este ultimo procedimiento, por considerar que es el tratamiento racional del estado patologico estudiado.