Inhibition of mitochondrial fission by Drp-1 blockade by short-term leptin and Mdivi-1 treatment improves white adipose tissue abnormalities in obesity and diabetes

Background: Obesity and type 2 diabetes are chronic diseases characterized by insulin resistance, mitochondrial dysfunction and morphological abnormalities. Objective: We have investigated if dysregulation of mitochondrial dynamics and biogenesis is involved in an animal model of obesity and diabetes. Methods: The effect of short-term leptin and mdivi-1 – a selective inhibitor of Drp-1 fission-protein – treatment on mitochondrial dynamics and biogenesis was evaluated in epididymal white adipose tissue (WAT) from male ob/ob mice. Results: An increase in Drp-1 protein levels and a decrease in Mfn2 and OPA-1 protein expression were observed with enhanced and sustained mitochondrial fragmentation in ob/ob mice compared to wt C57BL/6 animals (p < 0.05). The content of mitochondrial DNA and PGC-1α mRNA expression –both parameters of mitochondrial biogenesis– were reduced in ob/ob mice (p < 0.05). Treatment with leptin and mdivi-1 significantly increased mitochondrial biogenesis, improved fusion-to-fission balance and attenuated mitochondrial dysfunction, thus inducing white-to-beige adipocyte transdifferentiation. Measurements of glucose and lipid oxidation in adipocytes revealed that both leptin and mdivi-1 increase substrates oxidation while in vivo determination of blood glucose concentration showed decreased levels by 50% in ob/ob mice, almost to the wt level. Conclusions: Pharmacological targeting of Drp-1 fission protein may be a potential novel therapeutic tool for obesity and type 2 diabetes.Fil: Finocchietto, Paola Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Perez, Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Blanco, Guillermo Armando C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Miksztowicz, Verónica Julieta. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Fisiopatología y Bioquímica Clínica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Marotte, Clarisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Morales, C.. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Patología; ArgentinaFil: Peralta, Jorge Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Berg, G.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Instituto de Fisiopatologia y Bioquimica Clinica.; ArgentinaFil: Poderoso, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Poderoso, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Carreras, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentin

Indirect ultraviolet photodesorption from CO:N2 binary ices - an efficient grain-gas process

UV ice photodesorption is an important non-thermal desorption pathway in many interstellar environments that has been invoked to explain observations of cold molecules in disks, clouds and cloud cores. Systematic laboratory studies of the photodesorption rates, between 7 and 14 eV, from CO:N2 binary ices, have been performed at the DESIRS vacuum UV beamline of the synchrotron facility SOLEIL. The photodesorption spectral analysis demonstrates that the photodesorption process is indirect, i.e. the desorption is induced by a photon absorption in sub-surface molecular layers, while only surface molecules are actually desorbing. The photodesorption spectra of CO and N2 in binary ices therefore depend on the absorption spectra of the dominant species in the subsurface ice layer, which implies that the photodesorption efficiency and energy dependence are dramatically different for mixed and layered ices compared to pure ices. In particular, a thin (1-2 ML) N2 ice layer on top of CO will effectively quench CO photodesorption, while enhancing N2 photodesorption by a factors of a few (compared to the pure ices) when the ice is exposed to a typical dark cloud UV field, which may help to explain the different distributions of CO and N2H+ in molecular cloud cores. This indirect photodesorption mechanism may also explain observations of small amounts of complex organics in cold interstellar environments.Comment: 21 pages 5 figure

New record of grasshopper (Orthoptera: acrididae & romaleidae) defoliators and population dynamics of insects on crops of Heliconia spp. in the Amazon.

Apesar da expansão da ?oricultura, pouco se sabe sobre insetos associados à cultura no norte do Brazil. O objetivo foi identi?car as principais espécies de gafanhotos desfolhadores, associados a cultivos de Heliconia spp. na região Nordeste do Estado do Pará, Brazil, nas cidades de Castanhal, Belém e Benevides de agosto de 2004 a março de 2005. Os representantes com maior abundância desses municípios foram dos herbívoros da ordem Coleoptera, Thysanoptera, Hemiptera e Orthoptera. Os invíduos coletados de Orthoptera foram Cornops frenatum frenatum (Marshall) e Eutropidacris cristata L. (Orthoptera: Acrididae), Prionolopha serrata L. e Chromacris speciosa Thunberg (Orthoptera: Romaleidae), que apresentam potencial de danos ao cultivo de culturas de helicônias no Nordeste do Estado do Pará, Brazil

Trichospilus diatraeae (Hymenoptera: eulophidae): a potential biological control agent of Lepidopteran pests of oil palm in the brazilian Amazon.

A expansão da monocultura da palma do óleo (Elaeis guineensis) pode favorecer pragas como as lagartas Opsiphanes invirae Hübner, Brassolis sophorae L. (Lepidoptera: Nymphalidae) e Eupalamides cyparissias (Fabricius) (Lepidoptera: Castniidae). O objetivo foi avaliar o potencial de Trichospilus diatraeae Cherian & Margabandhu (Hymenoptera: Eulophidae) como parasitóide de pupas de lepidópteras-praga da palma do óleo. Cinquenta fêmeas de T. diatraeae foram mantidas um tubo de ensaio por 48 horas com uma pupa dos seguintes hospedeiros: O. invirae, B. sophorae ou E. cyparissias, com, até, dois dias de idade. Trichospilus diatraeae realizou o parasitismo nas três espécies de Lepidoptera, mas obteve potencial reprodutivo em pupas de O. invirae e B. sophorae. Isto sugere que este parasitoide, de hábito polífago, pode representar uma alternativa para o controle de pragas de lepidópteros da palma de óleo na Amazônia brasileir

Wavelength-Dependent UV Photodesorption of Pure N2N_2 and O2O_2 Ices

Context: Ultraviolet photodesorption of molecules from icy interstellar grains can explain observations of cold gas in regions where thermal desorption is negligible. This non-thermal desorption mechanism should be especially important where UV fluxes are high. Aims: $N_2$ and $O_2$ are expected to play key roles in astrochemical reaction networks, both in the solid state and in the gas phase. Measurements of the wavelength-dependent photodesorption rates of these two infrared-inactive molecules provide astronomical and physical-chemical insights into the conditions required for their photodesorption. Methods: Tunable radiation from the DESIRS beamline at the SOLEIL synchrotron in the astrophysically relevant 7 to 13.6 eV range is used to irradiate pure $N_2$ and $O_2$ thin ice films. Photodesorption of molecules is monitored through quadrupole mass spectrometry. Absolute rates are calculated by using the well-calibrated CO photodesorption rates. Strategic $N_2$ and $O_2$ isotopolog mixtures are used to investigate the importance of dissociation upon irradiation. Results: $N_2$ photodesorption mainly occurs through excitation of the $b^1\sqcap_u$ state and subsequent desorption of surface molecules. The observed vibronic structure in the $N_2$ photodesorption spectrum, together with the absence of $N_3$ formation, supports that the photodesorption mechanism of $N_2$ is similar to CO, i.e., an indirect DIET (Desorption Induced by Electronic Transition) process without dissociation of the desorbing molecule. In contrast, $O_2$ photodesorption in the 7−13.6 eV range occurs through dissociation and presents no vibrational structure. Conclusions: Photodesorption rates of $N_2$ and $O_2$ integrated over the far-UV field from various star-forming environments are lower than for CO. Rates vary between $10^{-3}$ and $10^{-2}$ photodesorbed molecules per incoming photon.Astronom

Development of a manometric monitoring method for early detection of air microbiological contamination in the bloodstream

Atmospheric air is a microbial habitat of pathogenic bioaerosols that may pose serious risks to humans. A commonly laboratory-based approach for the diagnosis of such infections in the bloodstream is the blood culture analysis. Its clinical relevance is attributed to the fact that these infections are characterized by high rates of morbidity and mortality, requiring the need for efficient methods for rapid diagnosis. For this reason, our study aimed to develop a method of manometric monitoring for the rapid detection of viable microorganisms in blood culture vials. A methodology was developed to detect pressure variation in intra-vials through a manometric instrument that was coupled to vials of blood culture containing culture broth that allowed microbial growth. This device allowed the early detection of microbial activity based on the production or use of intra-flask gases as a result of microbial metabolic activity. The analyzed variables were the pressure as a function of time, microbial species, and culture medium. The highest pressure found in the flasks without microorganisms was 40 mmHg between 2 and 6 h, and the lowest pressure was 42 mmHg between 21 and 24 h. The variation of the internal pressure in blood culture flasks according to different groups of microorganisms as a function of time demonstrated that the fermentative gram-negative bacilli and gram-positive cocci exhibited a significant increase in relation to their respective control groups (p < 0.001). The non-fermenting gram-negative bacilli showed expected results in relation to the pressure variation in which the production of negative pressures was noticed during the period of analysis, with a significant difference with respect to their control groups (p < 0.001). The developed methodology for the early detection of microorganisms responsible for bloodstream infection was demonstrated to be effective.e Fundação de Apoio à Pesquisa e à Inovação Tecnológica do Estado de Sergipe-Program Centelha (FAPITEC/SE) and by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and Portuguese Science and Technology Foundation (FCT) through the project UIDB/04469/2020 (strategic fund) funded by national funds, and co-financed Education (FCT/MEC) from national funds and FEDER, under the Partnership Agreement PT2020info:eu-repo/semantics/publishedVersio