A Physiological behavior and tolerance of Lactuca sativa to lead nitrate and silver nitrate heavy metals / Comportamento fisiológico e tolerância de Lactuca sativa aos metais pesados nitrato de chumbo e nitrato de prata

This study goal to evaluate the effects of different concentrations of lead (Pb) and silver (Ag) on germination, initial growth and anatomical alterations of Lactuca sativa L. Plants use various mechanisms to reduce the impacts caused by anthropic action, such as xenobiotic elements of soils and water contaminated by heavy metals. These metals were supplied as lead nitrate and silver nitrate and the following treatments were established: control for both metals, maximum dose of heavy metals, for arable soils, allowed by the National Council of the Environment (Ag = 25 mg. Kg-1, Pb = 180 mg. Kg-1), double (Ag = 50 mg. Kg-1, Pb = 360 mg. Kg-1) and triple (Ag = 75 mg. Kg-1, Pb = 540 mg. Kg -1) of this dosage. Vigor and germination tests of the seeds and possible anatomical changes in the leaves and roots of lettuce plants were performed. The species showed a high capacity to germinate under Pb and Ag stress, and the germination was never completely inhibited; however, the germination decreased with increasing Pb concentrations, but not under Ag stress. The use of increasing doses of metals reduced seed vigor and increased chlorophyll content. An increase in biomass was also observed in plants from treatments submitted to Pb. The phytotoxic effects of metals were more pronounced at 15 days after sowing. Anatomically, L. sativa was influenced by metal concentrations, and had a reduction of up to 79.9% in root epidermis thickness at the highest Pb concentration, although some structures did not suffer significant changes. The results suggest that L. sativa presents tolerance to high concentrations of heavy metals, showing possible mechanisms to overcome the stress caused by these metals. In this research lettuce possibly used the mechanism of exclusion of metals retaining Pb and Ag in the roots preserving the photosynthetic apparatus in the aerial part of the plants. In general, the chemical element Pb was more toxic than Ag, in these experimental conditions.

Este estudo teve como objetivo avaliar os efeitos de diferentes concentrações de chumbo (Pb) e prata (Ag) na germinação, crescimento inicial e alterações anatômicas de Lactuca sativa L. As plantas utilizam vários mecanismos para reduzir os impactos causados pela ação antrópica, como elementos xenobióticos de solos e água contaminada por metais pesados. Esses metais foram fornecidos como nitrato de chumbo e nitrato de prata e foram estabelecidos os seguintes tratamentos: controle para ambos os metais, dose máxima de metais pesados, para solos cultiváveis, permitida pelo Conselho Nacional do Meio Ambiente (Ag = 25mg.Kg-1, Pb = 180mg.Kg-1), dobro (Ag = 50mg.Kg-1, Pb = 360mg.Kg-1) e triplo (Ag = 75mg.Kg-1, Pb = 540 mg.Kg -1) desta dosagem. Foram realizados testes de vigor e germinação das sementes e possíveis alterações anatômicas nas folhas e raízes das plantas de alface. A espécie apresentou alta capacidade de germinar sob estresse de Ag e Pb, e a germinação nunca foi completamente inibida; entretanto, a germinação diminuiu com o aumento das concentrações de Pb, mas não sob estresse de Ag. O uso de doses crescentes dos metais, reduziu o vigor das sementes e aumentou o teor de clorofila. Também foi observado aumento da biomassa nas plantas a partir dos tratamentos submetidos ao Pb. Os efeitos fitotóxicos dos metais foram mais acentuados aos 15 dias após a semeadura. Anatomicamente, L. sativa foi influenciada pelas concentrações de metais, e teve uma redução de até 79,9% na espessura da epiderme radicular na maior concentração de Pb, embora algumas estruturas não tenham sofrido alterações significativas. Os resultados sugerem que L. sativa apresenta tolerância a altas concentrações de metais pesados, mostrando possíveis mecanismos para superar o estresse causado por esses metais. Nesta pesquisa a alface possivelmente utilizou o mecanismo de exclusão de metais retendo Pb e Ag nas raízes preservando o aparato fotossintético na parte aérea das plantas. De forma geral o elemento químico Pb se mostrou mais tóxico que Ag, nestas condições experimentais.

A Physiological behavior and tolerance of Lactuca sativa to lead nitrate and silver nitrate heavy metals / Comportamento fisiológico e tolerância de Lactuca sativa aos metais pesados nitrato de chumbo e nitrato de prata

This study goal to evaluate the effects of different concentrations of lead (Pb) and silver (Ag) on germination, initial growth and anatomical alterations of Lactuca sativa L. Plants use various mechanisms to reduce the impacts caused by anthropic action, such as xenobiotic elements of soils and water contaminated by heavy metals. These metals were supplied as lead nitrate and silver nitrate and the following treatments were established: control for both metals, maximum dose of heavy metals, for arable soils, allowed by the National Council of the Environment (Ag = 25 mg. Kg-¹, Pb = 180 mg. Kg-¹), double (Ag = 50 mg. Kg-¹, Pb = 360 mg. Kg-¹) and triple (Ag = 75 mg. Kg-¹, Pb = 540 mg. Kg-¹) of this dosage. Vigor and germination tests of the seeds and possible anatomical changes in the leaves and roots of lettuce plants were performed. The species showed a high capacity to germinate under Pb and Ag stress, and the germination was never completely inhibited; however, the germination decreased with increasing Pb concentrations, but not under Ag stress. The use of increasing doses of metals reduced seed vigor and increased chlorophyll content. An increase in biomass was also observed in plants from treatments submitted to Pb. The phytotoxic effects of metals were more pronounced at 15 days after sowing. Anatomically, L. sativa was influenced by metal concentrations, and had a reduction of up to 79.9% in root epidermis thickness at the highest Pb concentration, although some structures did not suffer significant changes. The results suggest that L. sativa presents tolerance to high concentrations of heavy metals, showing possible mechanisms to overcome the stress caused by these metals. In this research lettuce possibly used the mechanism of exclusion of metals retaining Pb and Ag in the roots preserving the photosynthetic apparatus in the aerial part of the plants. In general, the chemical element Pb was more toxic than Ag, in these experimental conditions.

Este estudo teve como objetivo avaliar os efeitos de diferentes concentrações de chumbo (Pb) e prata (Ag) na germinação, crescimento inicial e alterações anatômicas de Lactuca sativa L. As plantas utilizam vários mecanismos para reduzir os impactos causados pela ação antrópica, como elementos xenobióticos de solos e água contaminada por metais pesados. Esses metais foram fornecidos como nitrato de chumbo e nitrato de prata e foram estabelecidos os seguintes tratamentos:controle para ambos os metais, dose máxima de metais pesados, para solos cultiváveis, permitida pelo Conselho Nacional do Meio Ambiente (Ag = 25mg.Kg-¹, Pb = 180mg.Kg-¹), dobro (Ag = 50mg.Kg-¹, Pb = 360mg.Kg-¹) e triplo (Ag = 75mg.Kg-¹, Pb = 540 mg.Kg-¹) desta dosagem. Foram realizados testes de vigor e germinação das sementes e possíveis alterações anatômicas nas folhas e raízes das plantas de alface. A espécie apresentou alta capacidade de germinar sob estresse de Ag e Pb, e a germinação nunca foi completamente inibida; entretanto, a germinação diminuiu com o aumento das concentrações de Pb, mas não sob estresse de Ag. O uso de doses crescentes dos metais, reduziu o vigor das sementes e aumentou o teor de clorofila. Também foi observado aumento da biomassa nas plantas a partir dos tratamentos submetidos ao Pb. Os efeitos fitotóxicos dos metais foram mais acentuados aos 15 dias após a semeadura. Anatomicamente, L. sativa foi influenciada pelas concentrações de metais, e teve uma redução de até 79,9% na espessura da epiderme radicular na maior concentração de Pb, embora algumas estruturas não tenham sofrido alterações significativas. Os resultados sugerem que L. sativa apresenta tolerância a altas concentrações de metais pesados, mostrando possíveis mecanismos para superar o estresse causado por esses metais. Nesta pesquisa a alface possivelmente utilizou o mecanismo de exclusão de metais retendo Pb e Ag nas raízes preservando o aparato [...].

A Physiological behavior and tolerance of Lactuca sativa to lead nitrate and silver nitrate heavy metals

Abstract This study goal to evaluate the effects of different concentrations of lead (Pb) and silver (Ag) on germination, initial growth and anatomical alterations of Lactuca sativa L. Plants use various mechanisms to reduce the impacts caused by anthropic action, such as xenobiotic elements of soils and water contaminated by heavy metals. These metals were supplied as lead nitrate and silver nitrate and the following treatments were established: control for both metals, maximum dose of heavy metals, for arable soils, allowed by the National Council of the Environment (Ag = 25 mg. Kg-1, Pb = 180 mg. Kg-1), double (Ag = 50 mg. Kg-1, Pb = 360 mg. Kg-1) and triple (Ag = 75 mg. Kg-1, Pb = 540 mg. Kg -1) of this dosage. Vigor and germination tests of the seeds and possible anatomical changes in the leaves and roots of lettuce plants were performed. The species showed a high capacity to germinate under Pb and Ag stress, and the germination was never completely inhibited; however, the germination decreased with increasing Pb concentrations, but not under Ag stress. The use of increasing doses of metals reduced seed vigor and increased chlorophyll content. An increase in biomass was also observed in plants from treatments submitted to Pb. The phytotoxic effects of metals were more pronounced at 15 days after sowing. Anatomically, L. sativa was influenced by metal concentrations, and had a reduction of up to 79.9% in root epidermis thickness at the highest Pb concentration, although some structures did not suffer significant changes. The results suggest that L. sativa presents tolerance to high concentrations of heavy metals, showing possible mechanisms to overcome the stress caused by these metals. In this research lettuce possibly used the mechanism of exclusion of metals retaining Pb and Ag in the roots preserving the photosynthetic apparatus in the aerial part of the plants. In general, the chemical element Pb was more toxic than Ag, in these experimental conditions.

Resumo Este estudo teve como objetivo avaliar os efeitos de diferentes concentrações de chumbo (Pb) e prata (Ag) na germinação, crescimento inicial e alterações anatômicas de Lactuca sativa L. As plantas utilizam vários mecanismos para reduzir os impactos causados pela ação antrópica, como elementos xenobióticos de solos e água contaminada por metais pesados. Esses metais foram fornecidos como nitrato de chumbo e nitrato de prata e foram estabelecidos os seguintes tratamentos: controle para ambos os metais, dose máxima de metais pesados, para solos cultiváveis, permitida pelo Conselho Nacional do Meio Ambiente (Ag = 25 mg.Kg-1, Pb = 180 mg.Kg-1), dobro (Ag = 50 mg.Kg-1, Pb = 360 mg.Kg-1) e triplo (Ag = 75 mg.Kg-1, Pb = 540 mg.Kg -1) desta dosagem. Foram realizados testes de vigor e germinação das sementes e possíveis alterações anatômicas nas folhas e raízes das plantas de alface. A espécie apresentou alta capacidade de germinar sob estresse de Ag e Pb, e a germinação nunca foi completamente inibida; entretanto, a germinação diminuiu com o aumento das concentrações de Pb, mas não sob estresse de Ag. O uso de doses crescentes dos metais, reduziu o vigor das sementes e aumentou o teor de clorofila. Também foi observado aumento da biomassa nas plantas a partir dos tratamentos submetidos ao Pb. Os efeitos fitotóxicos dos metais foram mais acentuados aos 15 dias após a semeadura. Anatomicamente, L. sativa foi influenciada pelas concentrações de metais, e teve uma redução de até 79,9% na espessura da epiderme radicular na maior concentração de Pb, embora algumas estruturas não tenham sofrido alterações significativas. Os resultados sugerem que L. sativa apresenta tolerância a altas concentrações de metais pesados, mostrando possíveis mecanismos para superar o estresse causado por esses metais. Nesta pesquisa a alface possivelmente utilizou o mecanismo de exclusão de metais retendo Pb e Ag nas raízes preservando o aparato fotossintético na parte aérea das plantas. De forma geral o elemento químico Pb se mostrou mais tóxico que Ag, nestas condições experimentais.

A Physiological behavior and tolerance of Lactuca sativa to lead nitrate and silver nitrate heavy metals.

This study goal to evaluate the effects of different concentrations of lead (Pb) and silver (Ag) on germination, initial growth and anatomical alterations of Lactuca sativa L. Plants use various mechanisms to reduce the impacts caused by anthropic action, such as xenobiotic elements of soils and water contaminated by heavy metals. These metals were supplied as lead nitrate and silver nitrate and the following treatments were established: control for both metals, maximum dose of heavy metals, for arable soils, allowed by the National Council of the Environment (Ag = 25 mg. Kg-1, Pb = 180 mg. Kg-1), double (Ag = 50 mg. Kg-1, Pb = 360 mg. Kg-1) and triple (Ag = 75 mg. Kg-1, Pb = 540 mg. Kg -1) of this dosage. Vigor and germination tests of the seeds and possible anatomical changes in the leaves and roots of lettuce plants were performed. The species showed a high capacity to germinate under Pb and Ag stress, and the germination was never completely inhibited; however, the germination decreased with increasing Pb concentrations, but not under Ag stress. The use of increasing doses of metals reduced seed vigor and increased chlorophyll content. An increase in biomass was also observed in plants from treatments submitted to Pb. The phytotoxic effects of metals were more pronounced at 15 days after sowing. Anatomically, L. sativa was influenced by metal concentrations, and had a reduction of up to 79.9% in root epidermis thickness at the highest Pb concentration, although some structures did not suffer significant changes. The results suggest that L. sativa presents tolerance to high concentrations of heavy metals, showing possible mechanisms to overcome the stress caused by these metals. In this research lettuce possibly used the mechanism of exclusion of metals retaining Pb and Ag in the roots preserving the photosynthetic apparatus in the aerial part of the plants. In general, the chemical element Pb was more toxic than Ag, in these experimental conditions.

Alginate microparticles as carriers for the UV filter 2-ethylhexyl 4-methoxycinnamate: Influence on photostability.

OBJECTIVE: The organic ultraviolet UVB filter 2-ethylhexyl 4-methoxycinnamate (EHMC) was encapsulated in microparticles (MPs) of sodium alginate and co-loaded with vitamin E (Vit.E) by an extrusion process using an aerodynamically assisted jetting (AAJ) methodology. The aim was to assess the effect of encapsulation concerning UVB filter release from the MPs and its photochemical stability. METHODS: The EHMC photostability was analysed by exposing the samples (both MPs in aqueous dispersion and incorporated in a cream preparation) during 1 h to simulated solar light. For the MPs (empty-MP, EHMC-MP and EHMC + Vit.E-MP), the morphology and size were characterized; while in the case of the encapsulated samples, the amount of EHMC-loading was determined. The release of EHMC was evaluated by adding EHMC-MP or EHMC + Vit.E-MP to 65% ethanol in water under mechanical stirring at 32°C. RESULTS: All MPs showed a homogeneous size distribution with a median of 90.5 ± 2.5 µm for EHMC-MP and 70.4 ± 1.14 µm for EHMC + Vit.E-MP. The encapsulation efficiency was 92.9% and 99.4% for EHMC-MP and EHMC + Vit.E-MP, respectively. The observed release from the MPs was lower than the dissolution of the pure UV filter. EHMC-MP and EHMC + Vit.E-MP were successfully incorporated into a cream formulation, with no evidence of phase separation or colour modification. Upon simulated light exposure, the photoisomerization/phototransformation of EHMC encapsulated in MPs and Vit.E-MP decreased as compared to free EHMC, both in aqueous dispersion and as a cream. The conformational ratio of the isomers (Z-/E-EHMC) was found to be the lowest in the presence of Vit.E. CONCLUSION: This work demonstrates that use of these alginate microparticulate carriers could enhance the effectiveness of sunscreen preparations containing this UVB filter.

OBJECTIF: Le filtre ultraviolet organique D'UVB 2-éthylhexyl 4-methoxycinnamate (EHMC) a été encapsulé dans des microparticules (MPs) d'alginate de sodium et co-chargé avec la vitamine E (Vit.E) par un processus d'extrusion utilisant une méthode de jet assisté aérodynamique (AAJ). L'objectif était d'évaluer l'effet de l'encapsulation concernant la libération du filtre UVB par les MPs et sa stabilité photochimique. MÉTHODES: La photostabilité EHMC a été analysée en exposant les échantillons (les deux MPs en dispersion aqueuse et incorporés dans une préparation de type crème) pendant 1 h à la lumière solaire simulée. Pour les MPs (MP-vide, EHMC-MP et EHMC - Vit.E-MP), la morphologie et la taille ont été caractérisées; tandis que dans le cas des échantillons encapsulés, la quantité de charge EHMC a été déterminée. Le relargage de l'EHMC a été évalué en ajoutant EHMC-MP ou EHMC - Vit.E-MP à 65% d'éthanol dans l'eau sous agitation mécanique à 32°C. RÉSULTATS: Tous les MP ont montré une distribution homogène de taille avec une médiane de 90,5 +- 2,5 µm pour EHMC-MP et de 70,4 +- 1,14 µm pour l'EHMC et Vit.E-MP. L'efficacité de l'encapsulation était de 92,9 % et 99,4 % pour EHMC-MP et EHMC - Vit.E-MP, respectivement. Le relargage observé des MPs était inférieur à la dissolution du filtre UV pur. EHMC-MP et EHMC - Vit.E-MP ont été incorporés avec succès dans une formulation de crème, sans aucune preuve de séparation de phase ou de modification des couleurs. Après exposition à la lumière simulée, la photoiomérisation/phototransformation de l'EHMC encapsulée dans les MPs et Vit.E-MP a diminué par rapport à l'EHMC libre, à la fois dans la dispersion aqueuse et la crème. Le rapport conformationnel des isomères (Z-/E-EHMC) s'est avéré le plus bas en présence de Vit.E.

In vitro and in silico evaluation of fucosterol from Sargassum horridum as potential human acetylcholinesterase inhibitor.

The fucosterol has been reported numerous biological activities. In this study, the activity in vitro of the fucosterol from Sargassum horridum as potential human acetylcholinesterase inhibitor was evaluated. The structural identification was obtained by nuclear magnetic resonance (NMR) spectroscopy and based on experimental data, we combined docking and molecular dynamics simulations coupled to the molecular-mechanics-generalized-born-surface-area approach to evaluating the structural and energetic basis for the molecular recognition of fucosterol and neostigmine at the binding site of acetylcholinesterase (AChE). In addition, the Lineweaver-Burk plot showed the nature of a non-competitive inhibition. The maximum velocity (Vmax) and the constant of Michaelis-Menten (Km) estimated for fucosterol (0.006 µM) were 0.015 1/Vo (ΔA/h and 6.399 1/[ACh] mM-1, respectively. While, for neostigmine (0.14 µM), the Vmax was 0.022 1/Vo (ΔA/h) and Km of 6.726 1/[ACh] mM-1, these results showed a more effective inhibition by fucosterol respect to neostigmine. Structural analysis revealed that neostigmine reaches the AChE binding site reported elsewhere, whereas fucosterol can act as a no-competitive and competitive acetylcholinesterase inhibitor, in agree with kinetic enzymatic experiments. Binding free energy calculations revealed that fucosterol reaches the acetylcholinesterase binding site with higher affinity than neostigmine, which is according to experimental results. Whereas the per-residue decomposition free energy analysis let us identify crucial residues involved in the molecular recognition of ligands by AChE. Results corroborate the ability of theoretical methods to provide crucial information at the atomic level about energetic and structural differences in the binding interaction and affinity from fucosterol with AChE. Communicated by Ramaswamy H. Sarma.

Postpartum follow up of gestational diabetes in a Tertiary Care Center.

BACKGROUND: Gestational diabetes is a risk factor for future development of type 2 diabetes. The primary aim of this study was to estimate the prevalence of postpartum glucose tolerance status evaluation in pregnancies complicated by gestational diabetes 6-12 weeks after delivery. The secondary one was to identify the factors that are implicated with postpartum glucose retesting. METHODS: This was a retrospective study performed with a cohort of women with gestational diabetes, with prenatal care and delivery at a tertiary care center, from January 2013 to April 2017. The diagnosis of gestational diabetes was based on IADPSG criteria (Fasting ≥ 92 mg/dl, 1 h ≥ 180 mg/dl and/or 2 h ≥ 153 mg/dl, respectively) and the diagnosis of type 2 diabetes and prediabetes were made using the 2016 ADA's criteria (fasting and 2 h after glucose load ≥ 126 mg/dl and/or ≥ 200 and 100-125 mg/dl and/or 140 and 199 mg/dl, respectively). All women had an appointment scheduled 6-12 weeks postpartum with the results of a 75-g oral glucose tolerance test (OGTT). RESULTS: Of the 152 evaluated women, 21 (13.8%) returned with the postpartum OGTT results. Of these, 9 (45.0%) had a diagnosis of prediabetes. The use of insulin during gestation was the only factor implicated in a higher adherence rate to postpartum testing OR 6.33 (p 0.002). No significance was found for other demographic and clinical variables (age, family income, years of study, parity, gestational age at first visit, smoking, family history of type 2 diabetes, diagnosis of gestational diabetes before the third trimester, pregestational body mass index, previous history of gestational diabetes and ethnicity). CONCLUSION: The majority of patients with gestational diabetes did not return postpartum to perform OGTT and in our study the only factor implicated in a higher postpartum return was the use of insulin during pregnancy. Considering that 45.0% were diagnosed with prediabetes, diabetes care teams should initially identify non-adherent patients.

Endometrial expression of estrogen and progesterone receptors in non-cyclic mares treated only with long-acting progesterone.

Administration of progesterone (P4) after estradiol is usually performed to prepare non-cyclic mares as embryo recipients. However, there are successful pregnancy reports after embryo transfer in non-cyclic mares treated only with progestins. The objective of this study was to evaluate endometrial gene expression and immunostaining for estrogen receptor alpha (ERα), beta (ERß) and progesterone receptor (PR) in seasonal anestrous mares treated with long acting P4 (LA P4). Endometrial tissue from eight seasonal anestrous mares was collected immediately before administration of 1.5 g of LA P4 and five days after. The receptors protein expression was evaluated by immunohistochemistry and the percentage of the immunostained area was determined by ImageJ software. Transcripts abundance for ERα, ERß and PR were determined by RT-qPCR. Blood samples were collected daily to measure plasma P4 concentrations. Protein expression for ERα was greater (p < 0.05) after LA P4 administration, although gene expression was not affected by treatment (p > 0.05). There was no difference for ERß protein expression (p = 0.07) and ERß gene expression was reduced (p < 0.05) after treatment. Gene and protein expression for PR was not altered (p > 0.05). In conclusion, endometrial PR and ERα expression patterns after LA P4 administration were similar to those previously found in protocols using estradiol prior to LA P4 to prepare non-cyclic mares as embryo recipients.

Administration of 2.5 mg of estradiol followed by 1,500 mg of progesterone to anovulatory mares promote similar uterine morphology, hormone concentrations and molecular dynamics to those observed in cyclic mares.

To test the hypothesis that the administration of 2.5 mg of estradiol benzoate (EB) followed by 1500 mg of long acting progesterone (LA P4) causes similar uterine changes and molecular dynamics in anovulatory mares to those observed in cyclic ones, we evaluated the changes of estrogen (ERα and ERß) and progesterone receptors (PR) in anestrous, transitional and cyclic mares by RT-qPCR and immunohistochemistry. In addition, we evaluated uterine edema, tonus and estrogens and progesterone plasma profile. Endometrial biopsies were taken from anestrous and transitional mares immediately before EB injection, 48 h after EB administration and five days after LA P4 was given. In cyclic mares, biopsies were collected at estrus and at five days after ovulation. Similar estrogen peaks were achieved after the injection of the single EB dose between treated and cyclic groups, as well as maximum uterine edema. Uterine tone was increased to diestrus levels after administration of 1500 mg of LA P4. Changes in relative abundance of transcripts for PR, ERα and ERß when progesterone stimulated endometrium was compared to estrogen stimulated endometrium were similar between cyclic and non-cyclic treated mares. However, apparent decreased PR in the endometrial glandular epithelium was not observed in non-cyclic mares five days after LA P4 administration as observed at five days after ovulation in cyclic mares. The protocol produced similar endometrial edema, uterine tonus and changes in relative abundance of PR, ERα and ERß transcripts to those observed in cyclic mares during late estrus and early diestrus, as well as similar estradiol and estrogen conjugate plasma concentrations.

Polyhydroxybutyrate and polyhydroxydodecanoate produced by Burkholderia contaminans IPT553.

AIMS: In this paper, we introduce a new Burkholderia contaminans capable of producing a newly characterized polymer. METHODS AND RESULTS: CG-MS and magnetic nuclear resonance 1 H and 13 C were used to determine the constitution of polymers produced in glucose, glucose with casein, sucrose and sucrose with casein. Three pairs of primers were used to find the polyhydroxyalkanoates (PHA) synthase class and sequence. The synthesized polymers were composed by short-chain length PHA (scl-PHA), especially polyhydroxybutyrate (PHB), and medium chain length PHA (mcl-PHA), especially polyhydroxydodecanoate (PHDd), and their concentration, constitution and molecular weight depend on carbon source used. The bacterium showed only class I synthase which could not explain the mcl-PHA production. CONCLUSIONS: Burkholderia contaminans has a class I PHA synthase and produces PHB combined to PHDd when cultivated in sucrose or glucose, and PHDd concentration is affected when casein is used. SIGNIFICANCE AND IMPACT OF THE STUDY: PHA are natural polymers produced by a wide range of bacteria. The presence of PHDd monomers confers to the polymer elastomeric properties. Previously, PHDd was only obtained when bacteria were cultivated in related carbon source. In this work, B. contaminansIPT553 produced PHB with PHDd using simple and low-cost carbon sources that can make possible the cheaper production of a more flexible biopolymer with crystallinity and elasticity different from the more common PHAs.

Parasitism and inflammation in ear skin and in genital tissues of symptomatic and asymptomatic male dogs with visceral leishmaniasis.

Canine visceral leishmaniasis (CVL) is transmitted through vector, although venereal transmission has been suggested. This study aimed to compare the parasitic loads and inflammatory processes in genital tissues with ear skin from seropositive male dogs. Forty-five seropositive dogs were separated into groups containing symptomatic (n = 23) and asymptomatic (n = 22) animals. The control group (n = 2) healthy animals with seronegative and negative results in direct parasitological test. Samples of ear tip skin, prepuce, glans penis, testis, epididymis, and prostate were collected for evaluation of parasitic load and inflammatory infiltrate. Although ear tip skin was the most intensely parasitized, prepuce and epididymis revealed no difference in parasitism when compared with ear tip skin (P > 0.05). Parasitic loads in testis and prostate were lower than other tissues (P < 0.05). Parasitism in glans penis was high, similar to prepuce and epididymis, but lower than ear tip skin. High parasitism was more frequent in symptomatic dogs than asymptomatic animals. Severe inflammatory processes were more frequent within the symptomatic animals compared with asymptomatic and more predominant in prepuce and epididymis. Ear tip skin and genital tissues presented signs of chronic inflammation. There were weak and moderate positive correlations between parasitic loads and inflammatory processes. Our results demonstrate that, likewise with the ear tip skin, the genital of seropositive dogs can carry a large number of Leishmania infantum amastigotes and this process are more intense in symptomatic animals. These data have important implications for understanding the possibility of venereal transmission of CVL.

Polyhydroxybutyrate and polyhydroxydodecanoate produced by burkholderia contaminans IPT553

AimsIn this paper, we introduce a new Burkholderia contaminans capable of producing a newly characterized polymer. Methods and ResultsCG-MS and magnetic nuclear resonance H-1 and C-13 were used to determine the constitution of polymers produced in glucose, glucose with casein, sucrose and sucrose with casein. Three pairs of primers were used to find the polyhydroxyalkanoates (PHA) synthase class and sequence. The synthesized polymers were composed by short-chain length PHA (scl-PHA), especially polyhydroxybutyrate (PHB), and medium chain length PHA (mcl-PHA), especially polyhydroxydodecanoate (PHDd), and their concentration, constitution and molecular weight depend on carbon source used. The bacterium showed only class I synthase which could not explain the mcl-PHA production. ConclusionsBurkholderia contaminans has a class I PHA synthase and produces PHB combined to PHDd when cultivated in sucrose or glucose, and PHDd concentration is affected when casein is used. Significance and Impact of the StudyPHA are natural polymers produced by a wide range of bacteria. The presence of PHDd monomers confers to the polymer elastomeric properties. Previously, PHDd was only obtained when bacteria were cultivated in related carbon source. In this work, B. contaminansIPT553 produced PHB with PHDd using simple and low-cost carbon sources that can make possible the cheaper production of a more flexible biopolymer with crystallinity and elasticity different from the more common PHAs.

Comparison of different regimens of estradiol benzoate treatments followed by long-acting progesterone to prepare noncycling mares as embryo recipients.

The present study evaluated the influence of different regimens of estradiol benzoate (EB) treatments followed by a single dose of long-acting progesterone (LA P4) on plasma estrogen and P4 concentrations in noncyclic mares prepared as embryo recipients. Twenty-one anestrous mares were distributed into three groups (n = 7 mares per group), according to the EB dose received (single dose of 2.5 mg, total of 5 mg in decreasing doses, and total of 10 mg in decreasing doses), which was followed by a single administration of 1500 mg of LA P4 in all groups. Mares were reevaluated during the ovulatory phase and seven of them became part of the cyclic nontreated control group. Ultrasonography was performed to monitor endometrial edema, and blood samples were collected to measure estradiol (E2), estrogen conjugate (EC), and P4 by RIA. Maximum uterine edema was achieved 24 hours after administration of EB in all treated groups. Maximum E2 concentrations were observed 24 hours after the first EB injection in treated groups and there were no differences (P > 0.05) among treatments. Maximum EC concentration was observed 24 hours after the single EB injection in the 2.5-mg group, whereas in the 5- and 10-mg groups EC peaks were observed 48 hours after the first EB administration. Maximum P4 concentrations were detected 24 hours after LA P4 injection, although higher P4 concentrations were observed in the group treated with 2.5 mg of EB than in that treated with 10 mg of EB (P < 0.05). Because P4 concentrations were reduced after administration of high doses of EB, we also measured 17α-hydroxyprogesterone (17-OH-P) to test the hypothesis that high concentrations of EB would accelerate the conversion of P4 to 17-OH-P. However, 17-OH-P concentrations paralleled P4 profile in all groups, irrespective of EB doses. In summary, the three EB treatment regimens induced similar E2 peaks, although the observation of EC peaks 24 hours after E2 peaks in the 5- and 10-mg groups indicate that an excess of E2 was given, which was converted into EC to be inactivated. Administration of 10 mg of EB reduced P4 concentrations 24 hours after LA P4 was given. We demonstrated that the mechanism by which this reduction occurred was not by an increase in P4 metabolism to 17α-OH-P. In conclusion, the use of 2.5 mg of EB followed by 1500 mg of LA P4 appears to be a more appropriate regimen to treat noncyclic mares, although additional studies are needed to verify embryo survival with this treatment dose.