Tug-of-War Driven by the Structure of Carboxylic Acids: Tuning the Size, Morphology, and Photocatalytic Activity of α-Ag2WO4.

Size and morphology control during the synthesis of materials requires a molecular-level understanding of how the addition of surface ligands regulates nucleation and growth. In this work, this control is achieved by using three carboxylic acids (tartaric, benzoic, and citric) during sonochemical syntheses. The presence of carboxylic acids affects the kinetics of the nucleation process, alters the growth rate, and governs the size and morphology. Samples synthesized with citric acid revealed excellent photocatalytic activity for the degradation process of Rhodamine B, and recyclability experiments demonstrate that it retains 91% of its photocatalytic activity after four recycles. Scavenger experiments indicate that both the hydroxyl radical and the hole are key species for the success of the transformation. A reaction pathway is proposed that involves a series of dissolution-hydration-dehydration and precipitation processes, mediated by the complexation of Ag+. We believe these studies contribute to a fundamental understanding of the crystallization process and provide guidance as to how carboxylic acids can influence the synthesis of materials with controlled size and morphology, which is promising for multiple other scientific fields, such as sensor and catalysis fields.

Dimethylformamide Preserves the Integrity of Cryopreserved Goat Semen in a Soybean Lecithin-Based Extender.

This study investigated the cryoprotectant effects of dimethylformamide (DMF), ethylene glycol (EG), and dimethyl sulfoxide (DMSO) as substitutes for glycerol (GLY) in a soybean lecithin (SL)-based extender in the cryopreservation of buck sperm. In this study, the semen of three Saanen bucks was individually extended in SL supplemented with 5% GLY (control), DMF, EG, or DMSO. After this, the extended semen was cryopreserved and two straws from each group were thawed (37°C for 30 seconds), pooled, and analyzed for sperm motion parameters, plasma membrane integrity (PMI), acrosomal integrity (ACI), and high mitochondrial membrane potential (HMMP). Samples were analyzed after 15 minutes (T0) and after 2 hours of incubation at 37°C (T2). The results revealed higher values of motility (total and progressive) and sperm motion parameters for DMF than the other cryoprotectants (p < 0.0001). PMI and HMMP did not differ (p > 0.05) between GLY and DMF, but ACI was higher (p < 0.01) for DMF compared with GLY. Based on these results, DMF and GLY samples were used in heterologous in vitro fertilization assays by using bovine oocytes (n = 337) obtained from a slaughterhouse. No differences (p > 0.05) were observed between GLY and DMF for unfertilized (GLY: 38.8%; DMF: 25.33%), pronucleus (GLY: 25.68%; DMF: 27.92%), and cleavage rates (GLY: 35.52%; DMF: 46.75%). Based on these results, it is concluded that DMF preserves sperm motion characteristics and ACI better than GLY, EG, and DMSO, and it is the penetrating cryoprotectant of choice for the cryopreservation of buck sperm in SL extender.

Diluent Containing Dimethylformamide Added With Sucrose Improves In Vitro Quality After Freezing/Thawing Stallion Sperm.

The aim of this study was to investigate the effects of sucrose on post-thawed equine semen quality. Semen samples (n = 24) were collected from six stallions. They were diluted (200 × 106 sperm/mL) in a freezing medium based on skimmed milk, egg yolk, dimethylformamide, and supplemented with sucrose at concentrations of 0 (Control), 25, 50, and 100 mM and in a commercial extender (BotuCrio). Subsequently, they were filled in straws (0.5 mL) and subjected to freezing and storage (-196°C). Immediately after thawing (37°C, 30 seconds), semen samples were evaluated for kinetics (CASA), plasma and acrosomal membrane integrity, and mitochondrial membrane potential (flow cytometry). The addition of 50 and 100mM sucrose to the freezing extender increased (P < .05) the parameters of TM, PM, VCL, VSL, and VAP, compared to the control group. The WOB parameter of the group supplemented with 100 mM sucrose was higher (P < .05) than the control group. Higher values ​​(P < .05) of ALH and BCF were observed in groups treated with sucrose (25, 50, and 100 mM), compared to BotuCrio. The semen frozen in the presence of 100 mM sucrose presented higher percentages (P < .05) of sperm with intact plasma and acrosomal membranes, and high mitochondrial membrane potential in relation to the other groups. It is concluded that the addition of sucrose to equine semen freezing extender increase motility (50 and 100 mM), plasma and acrosomal membrane integrity preserve, and high sperm mitochondrial membrane potential (100 mM) after thawing.

Effects of L-Carnitine on Equine Semen Quality During Liquid Storage.

l-Carnitine (LC) plays a key role in sperm metabolism, easily providing energy through ß-oxidation, which positively affects motility. The objective of this study was to investigate the association between blood plasma and seminal plasma LC levels, as well as the effect of LC as an additive in a skimmed milk-based extender during sperm storage at 5°C. In the first experiment, semen and blood samples from 14 Quarter Horse stallions were used. The LC content in blood plasma and seminal plasma was determined by spectrophotometry and their relationships with seminal parameters were evaluated. In the second experiment, ejaculates (n = 16) from four Quarter Horses were used. Each ejaculate was split into four treatment groups with different LC concentrations: 0 (control), 0.5, 1.0, and 2.0 mM. Sperm motility, integrity of plasma and acrosomal membranes, intracellular reactive oxygen species content, and plasma membrane stability were evaluated immediately after samples reached 5°C (0 hour) and after 24, 48, and 72 hours. There was a positive correlation (p < 0.05) between LC levels in seminal plasma with both sperm concentration and plasma and acrosomal membrane integrity. Furthermore, the addition of LC (1 and 2 mM) preserved the motility of equine sperm stored at 5°C. It was concluded that the concentrations of LC with seminal plasma present correlate to semen parameters and the addition of LC to skimmed milk-based extender preserves the motility of equine sperm stored at 5°C for up to 48 hours.

Gold nanochannels oxidation by confined water.

Confined and interstitial water has a key role in several chemical, physical and biological processes. It is remarkable that many aspects of water behavior in this regime (e.g., chemical reactivity) remain obscure and unaddressed. In particular for gold surfaces, results from simulations indicated that the first wetting layer would present hydrophilic behavior in contrast to the overall hydrophobic character of the bulk water on this surface. In the present work we investigate the properties of confined water on Au 〈111〉 nanochannels. Our findings, based on a large set of morphological, structural and spectroscopic experimental data and ab initio computer simulations, strongly support the hypothesis of hydrophilicity of the first wetting layer of the Au 〈111〉 surface. A unique oxidation process was also observed in the nanochannels driven by confined water. Our findings indicated that the oxidation product is Au(OH)3. Therefore, the Au surface reactivity against confined water needs to be considered for nanoscopic applications such as, e.g., catalysis in fine chemicals, pharmaceuticals, and the food industry green processes.

Immunolocalization of leptin and its receptor in the sheep ovary and in vitro effect of leptin on follicular development and oocyte maturation.

The aims of the study were to characterize leptin and it is receptor (LEPR) proteins immunoexpression in ovine ovaries and to evaluate the effects of leptin on development of secondary follicles cultured in vitro. The ovaries were collected and fixed for immunohistochemical analysis. Additional pairs of ovaries were collected and secondary follicles were isolated and cultured, for 18 days, in α-MEM+ alone or supplemented with 10 or 25 ng/mL of leptin. The antrum formation and fully grown oocytes rates were higher in 25 ng/mL leptin than all treatments. GSH levels and mitochondrial activity were higher in 10 or 25 ng/mL leptin than α-MEM+. 25 ng/mL leptin showed a higher percentage of MII than the α-MEM+. In conclusion, leptin and its receptor are expressed in ovine ovaries and 25 ng/mL leptin promoted higher in vitro maturation rates by improving follicular development, GSH levels and mitochondrial activity of ovine oocytes compared to control medium.

Effects of adiponectin during in vitro maturation of goat oocytes: MEK 1/2 pathway and gene expression pattern.

Recent studies have shown that adiponectin, an adipokine predominantly produced by adipose tissue, regulates several reproductive processes. However, the mechanisms of action of adiponectin on the maturation of goat oocytes remain to be determined. The aim of this study was to investigate whether (a) adiponectin influences the meiotic maturation of goat oocytes; (b) MAPK MEK 1/2 mediates the effects of adiponectin; and 3) adiponectin differentially affects mRNA relative abundance of genes relevant for adiponectin signal transduction in goat oocytes. The addition of adiponectin (5 µg/ml) during the maturation of goat oocytes resulted in a higher percentage of successful nuclear maturation compared to those of the group without adiponectin (p < 0.05). Adiponectin-stimulated nuclear oocyte maturation was significantly impaired by a mitogen-activated protein kinase MEK 1/2 inhibitor, U0126 (p < 0.05). There was no evidence of any adiponectin-induced difference in the relative transcript abundances of AdipoR1, AdipoR2, AMPKα1, AMPKα2, PPARα and PPARγ genes. In conclusion, these results indicate that adiponectin has a positive effect on the meiotic maturation of goat oocytes through the MAPK MEK 1/2 pathway. Furthermore, the adiponectin does not affect the relative abundance of genes relevant for adiponectin signal transduction in goat oocytes.

Expression of adiponectin and its receptors (AdipoR1 and AdipoR2) in goat ovary and its effect on oocyte nuclear maturation in vitro.

Adiponectin is an adipokine secreted primarily by adipocytes and is involved in the control of male and female reproductive functions. Circulating levels of adiponectin are inversely correlated with body fat mass, and its biological effects are predominantly mediated through two receptors, AdipoR1 and AdipoR2. The aim of the present study was to verify the expression of the adiponectin system (adiponectin and its receptors, AdipoR1 and AdipoR2) in goat ovary using qPCR and immunohistochemistry analyses and further investigate the in vitro effects of recombinant adiponectin (5 µg/mL and 10 µg/mL) on goat oocyte nuclear maturation. We demonstrated that the mRNA and proteins of the adiponectin system are present in goat ovary. Gene and protein expression of AdipoR1 and AdipoR2 was detected in follicular cells (oocyte, cumulus, granulosa and theca) of small and large antral follicles, while adiponectin mRNA was not detected in oocytes from small and large follicles or in large follicle cumulus cells. Finally, addition of various concentrations of adiponectin in maturation medium affected the number of oocytes that reached metaphase II. In conclusion, in the present study, we detected expression of adiponectin and its receptors AdipoR1 and AdipoR2 in goat ovarian follicles. Furthermore, we demonstrated that recombinant adiponectin increases nuclear maturation of goat oocytes in vitro.

The Effect of Canthaxanthin on the Quality of Frozen Ram Spermatozoa.

The addition of antioxidants to semen cryopreservation extenders has been employed for combating oxidative damage. This work aimed to evaluate the addition of carotenoid canthaxanthin to a cryopreservation extender of ram semen. Three breeder rams were used and, after semen collection, with 48-hour intervals between collection, the samples were included in the pool formation (n = 6). The experimental groups comprised 0 (control), 0.1, 1, 10, and 25 µM of canthaxanthin. After thawing (37°C/30 s) and incubation at 37°C for 2 hours, semen aliquots from each group were evaluated for sperm kinetics (CASA), the integrity of the plasma and acrosomal membranes (iPAM), intracellular reactive oxygen species (ROS) production, and lipid peroxidation (LPO) by flow cytometry associated with the image. The control group and canthaxanthin 1 µM after incubation at 37°C for 2 hours showed increases of curvilinear velocity and amplitude of lateral head displacement with decreases of linearity, straightness, and wobble (p < 0.05), which were not observed for the canthaxanthin 10 and 25 µM. The supplementation of a Tris-egg yolk extender with canthaxanthin had no effect on the iPAM, intracellular ROS production in viable spermatozoa, or LPO. In conclusion, supplementation with 10 and 25 µM of canthaxanthin in a Tris-egg yolk extender used for ram semen cryopreservation is able to protect ovine sperm from kinetic changes after incubation at 37°C for 2 hours post-thawing.

Expression of angiogenic factors and luteinizing hormone receptors in the corpus luteum of mares induced to ovulate with deslorelin acetate.

The effects of deslorelin acetate use in inducing ovulation need to be clarified to improve the results of equine embryo transfer. The mRNA abundance for angiogenic factors and LH receptor (LHR) in corpus luteum (CL) was studied in mares with natural (control group [CG]) and induced ovulation with deslorelin acetate (treatment group [TG]; follicles: ≥ 35 mm). Transrectal ultrasonography was used to verify the ovulation day, and on Days 4, 8, and 12 after ovulation (Day 0), CL samples were obtained through ultrasound-guided biopsy. The messenger RNA expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and LHR genes were analyzed by real-time polymerase chain reaction. A positive correlation was observed between VEGF and LHR (P < 0.00001, r = 0.78), and it was possible to detect higher LHR expression in the TG than in the CG on Day 4 (P < 0.05). Moreover, this expression was higher on Days 4 and 8 than on Day 12 in the TG. Basic fibroblast growth factor was also expressed in luteal tissue on all days for both groups; however, these differences were not significant. In conclusion, deslorelin acetate was effective for the induction of ovulation in mares, resulting in higher expression of LHR, especially on the fourth day after ovulation. In addition, VEGF expression was influenced by induced ovulation, with a lower level on Day 12, which is expected in nonpregnant mares.

Levantamento qualitativo de gêneros de parasitos em amostras fecais de jacarés criados comercialmente em sistema fechado no estado do Rio de Janeiro / Qualitative survey of parasites genera on fecal samples of alligators in a commercial closed farming system in the state of Rio de Janeiro

O objetivo desta pesquisa foi realizar um diagnóstico qualitativo dos gêneros de parasitos encontrados em amostras fecais ambientais de jacarés (Caiman latirostris Daudin, 1802), criados comercialmente em sistema fechado, no período de 2008 a 2009, no estado do Rio de Janeiro. Um total de 300 amostras foi coletado de 150 filhotes, 80 de animais de engorda e 70 de reprodução, e submetido a análises coproparasitológicas, de flutuação (método de Willis-Mollay) e sedimentação simples (método de Lutz), de acordo com Hoffmann (1987). As amostras foram visualizadas à luz da microscopia óptica. Os resultados obtidos evidenciaram a presença de oocistos de Eimeria e Isospora, cistos de Balantidium e ovos de Acanthostomum e Dujardinascaris.

The objective of this paper was to diagnose qualitatively parasite genera found in environmental fecal samples of alligators (Caiman latirostris Daudin, 1802) commercially bred from 2008 to 2009 in a closed farming system in the state of Rio de Janeiro. A total of 300 samples were collected from 150 young, 80 fattening and 70 breeding processed by two different methods, the flotation (method of Willis-Mollay) and simple sedimentation (method of Lutz), according to Hoffmann (1987). The samples were then examined by optical microscopy. The results revealed presence of Eimeria and Isospora oocysts, Balantidium cysts, and Acanthostomum and Dujardinascaris eggs.

Antimicrobial, antiproliferative and proapoptotic activities of extract, fractions and isolated compounds from the stem of Erythroxylum caatingae plowman.

In the study, we have examined the antitumor and antimicrobial activities of the methanol extract, the fractions, a fraction of total alkaloids and two alkaloids isolated from the stem of Erythroxylum caatingae Plowman. All test fractions, except the hexane fractions, showed antimicrobial activity on gram-positive bacteria and fungi. The acetate: methanol (95:5), acetate, chloroform and hexane fractions show the highest cytotoxicity activity against the NCI-H292, HEp-2 and K562 cell lines using MTT. The absence of hemolysis in the erythrocytes of mice was observed in these fractions and 6ß-Benzoyloxy-3α-(3,4,5- trimethoxybenzoyloxy) tropane (catuabine B). Staining with Annexin V-FITC and JC-1 was used to verify the mechanism of action of the compounds of E. caatingae that showed cytotoxicity less than 30 µg/mL in leukemic cells. After 48 h of incubation, we observed that the acetate: methanol (95:5), acetate, and chloroform fractions, as well as the catuabine B, increased in the number of cells in early apoptosis, from 53.0 to 74.8%. An analysis of the potential of the mitochondrial membrane by incorporation of JC-1 showed that most cells during incubation of the acetate: methanol (95:5) and acetate fractions (63.85 and 59.2%) were stained, suggesting the involvement of an intrinsic pathway of apoptosis.

Cytotoxic effect and apoptosis induction by Bothrops leucurus venom lectin on tumor cell lines.

Neoplastic transformation is the abnormal proliferation of cells. These transformations are often related to changes in cell surface glycoconjugates which can be detected by lectins. We evaluated the anti-tumor potential of BlL, a galactoside-binding lectin isolated from Bothrops leucurus venom as well as its cytotoxicity and hemolysis activity. The phosphatidylserine externalization and mitochondrial membrane potential were also determined. BlL exhibited cytotoxic activity against all tumor cell lines tested by induced phosphatidylserine externalization and mitochondrial depolarization, indicating cell death by apoptosis.

Detecção de Toxoplasma gondii no sêmen de ovinos naturalmente infectados / Toxoplasma gondii detection in the semen of naturally infected sheep

O objetivo deste trabalho foi estudar a eliminação de Toxoplasma gondii no sêmen de carneiros naturalmente infectados. Foram utilizados 65 reprodutores submetidos inicialmente à pesquisa de anticorpos anti-T. gondii por meio da técnica de imunofluorescência indireta (IFI). Os carneiros sorologicamente positivos foram submetidos à colheita de sêmen para detecção do DNA de T. gondii. Na sorologia observaram-se 6/65 (9,2 por cento) carneiros positivos, enquanto no PCR nested de sêmen 4/6 (66,6 por cento) carneiros foram positivos. Conclui-se que a detecção, por meio da técnica da PCR nested, da forma proliferativa de T. gondii no sêmen de carneiros naturalmente infectados, reforça a necessidade de se pesquisar sobre a possibilidade da transmissão horizontal do parasito via sêmen na espécie ovina.

The aim of this paper was to study the Toxoplasma gondii shedding in the semen of naturally infected rams. Sixty-five rams were initially submitted to anti-T. gondii antibody detection by indirect immunofluorescence (IIF). Serologically positive rams were then submitted to semen collection for T. gondii DNA detection. In the serology, 6/65 (9.2 percent) rams were positive, while in the nested PCR of semen there were 4/6 (66.6 percent) positive rams. It can be concluded that detection of the proliferative form of T. gondii in semen of naturally infected rams by the nested PCR technique reinforces the need to investigate possible horizontal transmission of this parasite via semen in sheep.