390 research outputs found
Fat area and lipid droplet morphology of porcine oocytes during in vitro maturation with trans-10, cis-12 conjugated linoleic acid and forskolin
Lipid droplets (LD) in porcine oocytes form a dark mass reaching almost all cytoplasm. Herein we investigated changes in fat areas, cytoplasmic tone and LD morphology during in vitro maturation (IVM) of porcine oocytes cultured with 100mM trans-10, cis-12 conjugated
linoleic acid (t10,c12 CLA) or 10mM forskolin at different time periods. Four groups were constituted: control, excipient, t10,c12 CLA and forskolin, with drugs being supplemented during 44 to 48h and the initial 22 to 24h in Experiments 1 and 2, respectively. In Experiment 3,
forskolin was supplemented for the first 2 h. Matured oocytes were inseminated with frozen-thawed boar semen and cleavage rate recorded. Before and during IVM, samples of oocytes were evaluated for LD, total and fat areas and fat gray value or for meiotic progression. Results showed that forskolin supplementation during 44 to 48 h or 22 to 24 h inhibits oocyte maturation (exp. 1: forskolin = 5.1±8.0%, control = 72.6±5.0%; exp. 2: forskolin =24.3±7.4%, control =71.6±5.6%) and cleavage (exp. 1: forskolin=0.0±0.0%, control=55.4±4.1%; exp. 2: forskolin=8.3±3.3%, control=54.5±3.0%). Forskolin also reduced oocyte and fat areas. In Experiment 3, forskolin negative effect on oocyte maturation and cleavage disappeared, although minor (P<0.03) LD and oocyte fat areas were identified at 22 to 24 h of IVM. Oocytes supplemented with t10,c12 CLA during 44 to 48h presented a lighter (P<0.04) colour tone cytoplasm than those of control and forskolin. In conclusion, t10,c12 CLA and forskolin were capable of modifying the distribution and morphology of cytoplasmic LD during porcine oocyte maturation, thus reducing its lipid content in a time-dependent manner
A utilização de sémen fresco na fertilização in vitro de embriões ovinos melhora a qualidade dos blastocistos na raça portuguesa Merino
A produção de embriões em ovinos é uma tarefa difícil, exigindo experiência e condições onerosas, principalmente na
produção de embriões in vivo. A recolha sistemática de oócitos em animais de matadouro ou em animais vivos por ovum
pick-up, permite a produção in vitro de embriões (IVP), em larga escala e menos dispendiosa, nos pequenos ruminantes.
Esta possibilidade é importante não só como fonte de embriões mas também de oócitos e zigotos para fins comerciais ou de
investigação, facilitando a sua disponibilidade em tecnologias emergentes tais como a clonagem ou a transgénese. Para IVP
foram desenvolvidos vários protocolos de maturação, utilizando fertilização in vitro (IVF) com sémen fresco ou congelado.
Em Portugal, a produção de embriões in vitro foi somente realizada com sémen congelado dada a sua disponibilidade em
condições de rotina. Contudo, o sémen fresco poderá melhorar a produção de embriões frescos ou criopreservados.
Este trabalho teve como objectivo comparar a eficiência da IVP em ovinos usando diferentes protocolos de maturação de
oócitos e IVF com sémen fresco ou congelado. Oócitos (n=1768) recolhidos em matadouro foram maturados em meio
TCM199 com 100 μM cisteamine, 10 ng mL-1 EGF, 10 μg mL-1 E2 e gentamicina (mat A, n=692) ou suplementada com
10 μg mL-1 FSH e 0,3 mM piruvato de sódio (mat B, n=707) a 39 ºC e 5% CO2 durante 22h. O sémen fresco (FS) e
congelado/descongelado (TS) de carneiros de raça Merino Branco (n=3) foi lavado ou submetido a swim-up,
respectivamente. Após a fertilização (18h p.i.), os presumíveis zigotos foram cultivados em meio de fluido sintético do
oviducto (SOF) enriquecido com aminoácidos e BSA a 38,5 ºC, em atmosfera humidificada com 5% O2, 5% CO2 e 90% N2
até ao estadio de 2-4-8 células. Após clivagem, o desenvolvimento embrionário prosseguiu até ao estadio de blastocisto em
meio SOF, BSA e 10% FCS. A qualidade foi avaliada no dia 6-7, classificando-se como bons, médios e maus, baseado nos
parâmetros IETS. Os dados das taxas de produção embrionária foram analisados utilizando ANOVA. Foi utilizado o teste
de Mann-Whitney U para avaliação da qualidade dos embriões.
Os diferentes protocolos de maturação não interferiram (p>0,05) quer com as taxas de maturação quer com as taxas de
produção de embriões. A qualidade embrionária foi superior (p=0,004) na fertilização com sémen fresco (bom:
FS=40,1±8,0% vs TS=32,9±5,6%; média: FS=20,1±4,7% vs TS=35,7±5,8%; má: FS=39,8±9,8% vs TS=31,4±7,6%).
Em conclusão, estes resultados preliminares mostram que o sémen fresco de carneiro pode ser facilmente utilizado
para fertilização in vitro e melhora a qualidade dos embriões produzidos.#Embryo production in sheep is a difficult task demanding experience and expensive facilities, particularly when dealing
with in vivo embryo production. Easy ways to obtain ovine embryos consist of collecting oocytes at slaughterhouses or
systematically pick them up from live animals, allowing a large scale and cheaper in vitro embryo production (IVP) for
small ruminants. Those are important sources of embryos, oocytes and zygotes for commercial, laboratorial and research
proposes, making easier the availability of resources for emerging techniques like cloning or transgenesis. For IVP, several
oocyte maturation protocols have been developed using fertilization (IVF) either with fresh or frozen-thawed semen. In
Portugal, IVP has been done through IVF using cryopreserved semen because it is easily available for routine use.
However, the use of fresh semen could improve embryo production and cryopreservation results.
The aim of this work was to compare the efficiency of in vitro embryo production in ovine using different oocyte
maturation protocols and fresh or frozen semen for IVF.
Abattoir-derived oocytes (n=1768) were matured in TCM199, 10 μM cysteamine, 10 ng mL-1 EGF, 10 μg mL-1 E2 and
gentamicin (mat A, n=692) or plus 10 μg mL-1 FSH and 0.3 mM sodium piruvate (mat B, n=707) at 39 ºC and 5% CO2 for
22h. Prior to fertilization, either fresh (FS) or frozen/thawed (TS) semen from Merino rams (n=3) was washed or submitted
to swim-up respectively. Presumptive zygotes (18h p.i.) were cultured in synthetic oviductal fluid (SOF) enriched with
aminoacids and 6 mg mL-1 BSA at 38.5 ºC, under 5% O2, 5% CO2 and 90% N2 in an humidified atmosphere until the stage
of 2-4-8 cell embryos. After assessing cleavage, embryo development proceeded until the blastocyst stage in SOF+BSA and
10% FCS. Quality was evaluated on D6-7 by scoring embryos as good, fair and bad based on IETS guidelines. Data from
embryo production rates were analysed using ANOVA. Mann-Whitney U test was used for embryo quality evaluation.
Different maturation protocols did not interfere (P>0.05) either on maturation or on embryo quality or production rates.
Embryo quality was higher (P=0.004) when fertilization was accomplished with fresh semen (good: FS=40.1±8.0% vs
TS=32.9±5.6%; fair: FS=20.1±4.7% vs TS=35.7±5.8%; bad: FS=39.8±9.8% vs TS=31.4±7.6%).
Preliminar results show that ram fresh semen can be easily used for in vitro fertilization and improves the quality of
produced embryos
Intensive Blood Pressure Treatment Reduced Stroke Risk in Patients With Albuminuria in the SPRINT Trial
Background and Purpose- Albuminuria is associated with stroke risk among individuals with diabetes. However, the association of albuminuria with incident stroke among nondiabetic patients is less clear. Methods- We performed a post hoc analysis of the SPRINT (Systolic Blood Pressure Intervention Trial), which examined the effect of higher versus lower intensity blood pressure management on mortality in 8913 participants without diabetes. We fit unadjusted and adjusted Cox proportional hazards models to estimate the association of baseline albuminuria (urinary albumin-to-creatinine ratio ≥30 mg/g versus<30 mg/g) with stroke risk. We also assessed effect modification according to treatment arms. Results- Mean age was 68±9 years, 35% were female, and 30% were black. Median follow-up was 3.2 years, and 19% patients had baseline albuminuria. Incident stroke occurred in 129 individuals during follow-up. Albuminuria was associated with increased stroke risk (unadjusted hazard ratio, 2.24; 95% CI, 1.55-3.23; adjusted hazard ratio 1.73; 95% CI, 1.17-2.56). The association of albuminuria with incident stroke differed according to the randomized treatment arm (P interaction=0.03). In the intensive treatment arm, the association of albuminuria and stroke was nonsignificant (unadjusted hazard ratio, 1.25; 95% CI, 0.69-2.28), whereas, in the standard treatment arm, it was significant (unadjusted hazard ratio, 3.44; 95% CI, 2.11-5.61). Conclusions- In a post hoc analysis of SPRINT, baseline albuminuria (versus not) was associated with a higher risk of incident stroke, but this relationship appeared to be restricted to those in the standard treatment arm. Further studies are required to conclusively determine if reduction of albuminuria in itself is beneficial in reducing stroke risk. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062.info:eu-repo/semantics/publishedVersio
Scoping review of cytolytic vaginosis literature
Background: Cytolytic vaginosis (CV) is a little-known, controversial condition that is typically not considered for women presenting with vulvovaginitis symptoms. Objective: The objective of this scoping review was to identify and compile the global evidence on CV.
Methods: A medical librarian searched Prospero, Wiley Cochrane Library, Ovid Embase, Ovid Medline, EBSCO CINAHL, ProQuest Dissertations and Theses Global, and Scopus, from inception to April 4, 2019 and updated to October 17, 2021. Studies were eligible if they discussed CV. Two independent reviewers conducted study selection and data extraction.
Results: Sixty-four studies were identified, with 67% of studies (n = 43) published since 2007. Studies were from around the world, including the United States (28%, n = 18), Brazil (11%, n = 7), Portugal (11%, n = 7), and China (11%, n = 7). Fifty percent of studies (n = 32) were reviews; the remainder were observational; and of these, 78% (n = 25) were cross-sectional. The most frequent topics included: diagnosis (19%, n = 12), prevalence (17%, n = 11), and overview of CV (50%, n = 32). Evidence for prevalence in symptomatic women (median prevalence of 5%, interquartile range 3%-8%) was based only on 16% of studies (n = 10) with minimal evidence on prevalence in asymptomatic women and across different geographic regions. Microbiological findings, including abundant lactobacilli and fragmented epithelial cells, were found useful to distinguish between CV and vulvovaginal candidiasis, and Lactobacillus crispatus was noted to dominate the vaginal flora in women with CV. Most studies used subjective criteria to diagnose CV as the condition lacks gold-standard microscopic criteria. The suggested primary treatment (baking soda irrigations) was largely based on expert opinion, and there was minimal evidence on associations between CV and other conditions.
Conclusion: Knowledge gaps currently exist in all realms of CV research. Additional research is needed to confirm the validity of CV and ensure that women are diagnosed and treated effectively.info:eu-repo/semantics/publishedVersio
Vocal Communications and the Maintenance of Population Specific Songs in a Contact Zone
Bird song has been hypothesized to play a role in several important aspects of the biology of songbirds, including the generation of taxonomic diversity by speciation; however, the role that song plays in speciation within this group may be dependent upon the ability of populations to maintain population specific songs or calls in the face of gene flow and external cultural influences. Here, in an exploratory study, we construct a spatially explicit model of population movement to examine the consequences of secondary contact of populations singing distinct songs. We concentrate on two broad questions: 1) will population specific songs be maintained in a contact zone or will they be replaced by shared song, and 2) what spatial patterns in the distribution of songs may result from contact? We examine the effects of multiple factors including song-based mating preferences and movement probabilities, oblique versus paternal learning of song, and both cultural and genetic mutations. We find a variety of conditions under which population specific songs can be maintained, particularly when females have preferences for their population specific songs, and we document many distinct patterns of song distribution within the contact zone, including clines, banding, and mosaics
Selected reactive oxygen species and antioxidant enzymes in common bean after Pseudomonas syringae pv. phaseolicola and Botrytis cinerea infection
Phaseolus vulgaris cv. Korona plants were
inoculated with the bacteria Pseudomonas syringae pv.
phaseolicola (Psp), necrotrophic fungus Botrytis cinerea
(Bc) or with both pathogens sequentially. The aim of the
experiment was to determine how plants cope with multiple
infection with pathogens having different attack strategy.
Possible suppression of the non-specific infection with
the necrotrophic fungus Bc by earlier Psp inoculation was
examined. Concentration of reactive oxygen species
(ROS), such as superoxide anion (O2
-) and H2O2 and
activities of antioxidant enzymes such as superoxide dismutase
(SOD), catalase (CAT) and peroxidase (POD) were
determined 6, 12, 24 and 48 h after inoculation. The
measurements were done for ROS cytosolic fraction and
enzymatic cytosolic or apoplastic fraction. Infection with
Psp caused significant increase in ROS levels since the
beginning of experiment. Activity of the apoplastic
enzymes also increased remarkably at the beginning of
experiment in contrast to the cytosolic ones. Cytosolic
SOD and guaiacol peroxidase (GPOD) activities achieved
the maximum values 48 h after treatment. Additional forms
of the examined enzymes after specific Psp infection were
identified; however, they were not present after single Bc
inoculation. Subsequent Bc infection resulted only in
changes of H2O2 and SOD that occurred to be especially
important during plant–pathogen interaction. Cultivar Korona
of common bean is considered to be resistant to Psp and mobilises its system upon infection with these bacteria.
We put forward a hypothesis that the extent of defence
reaction was so great that subsequent infection did not
trigger significant additional response
PRODUTOS DO INTEMPERISMO E AVALIAÇÃO DO NÍVEL DE DETERIORAÇÃO EM ROCHAS ORNAMENTAIS DA FORTALEZA DE SANTA CRUZ (NITERÓI, RJ)
DOI 10.12957/tamoios.2012.5084
RESUMO A Fortaleza de Santa Cruz, magnífico exemplo da arquitetura dos tempos da chegada dos europeus ao nosso continente, começou a ser construída por volta de 1555 na entrada da Baía de Guanabara (Niterói, RJ) com blocos de gnaisse facoidal local. De modo geral, rochas empregadas em construções em ambientes litorâneos e urbanos são expostas ao sal marinho, bem como, aos poluentes CO2, S e N e, em decorrência disso, os processos relacionados ao intemperismo podem causar danos consideráveis a essas construções. Na Fortaleza de Santa Cruz foram identificados diversos tipos de crostas (negra, de sal, orgânica, “flowstones”) e estalactites como produtos do intemperismo. A intensidade dos processos é diferente nos três pavimentos que compõem a Fortaleza, levando a níveis distintos de deterioração dos blocos de rocha, em função da circulação, teor de umidade e de sal no ar em cada pavimento.
Palavras-chaves: intemperismo; rochas ornamentais; crosta negra; dissolução.
ABSTRACT The Santa Cruz Fort, a magnificent example of architecture at the time of arrival of the Europeans to our continent, began to be constructed at about 1555 at the entrance of the Guanabara Bay (Niterói, RJ) with local blocks of augen gnaiss. In general, rocks employed in constructions in coastal and urban environments are exposed to sea derived salts and pollutants such as CO2, S and N and, as consequence of that, weathering related processes can cause considerable damage to these constructions. In the Santa Cruz Fort, various types of crusts (black, salt, organic, flowstones) and stalactites have been identified as weathering products. The intensity of such processes is different in the Fort’s three main floors and that leads to distinct deteriorations levels of the blocks of rock in each floor, a function of air circulation, humidity and salt content.
Keywords: Weathering; building stones; black crust; dissolution
Considerations regarding the dominance of Cylindrospermopsis raciborskii under low light availability in a low phosphorus lake
The neurogenic effects of exogenous neuropeptide Y: early molecular events and long-lasting effects in the hippocampus of trimethyltin-treated rats.
Modulation of endogenous neurogenesis is regarded as a promising challenge in neuroprotection. In the rat model of hippocampal neurodegeneration obtained by Trimethyltin (TMT) administration (8 mg/kg), characterised by selective pyramidal cell loss, enhanced neurogenesis, seizures and cognitive impairment, we previously demonstrated a proliferative role of exogenous neuropeptide Y (NPY), on dentate progenitors in the early phases of neurodegeneration. To investigate the functional integration of newly-born neurons, here we studied in adult rats the long-term effects of intracerebroventricular administration of NPY (2 \ub5g/2 \ub5l, 4 days after TMT-treatment), which plays an adjuvant role in neurodegeneration and epilepsy. Our results indicate that 30 days after NPY administration the number of new neurons was still higher in TMT+NPY-treated rats than in control+saline group. As a functional correlate of the integration of new neurons into the hippocampal network, long-term potentiation recorded in Dentate Gyrus (DG) in the absence of GABAA receptor blockade was higher in the TMT+NPY-treated group than in all other groups. Furthermore, qPCR analysis of Kruppel-like factor 9, a transcription factor essential for late-phase maturation of neurons in the DG, and of the cyclin-dependent kinase 5, critically involved in the maturation and dendrite extension of newly-born neurons, revealed a significant up-regulation of both genes in TMT+NPY-treated rats compared with all other groups. To explore the early molecular events activated by NPY administration, the Sonic Hedgehog (Shh) signalling pathway, which participates in the maintenance of the neurogenic hippocampal niche, was evaluated by qPCR 1, 3 and 5 days after NPY-treatment. An early significant up-regulation of Shh expression was detected in TMT+NPY-treated rats compared with all other groups, associated with a modulation of downstream genes. Our data indicate that the neurogenic effect of NPY administration during TMT-induced neurodegeneration involves early Shh pathway activation and results in a functional integration of newly-generated neurons into the local circuit
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