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1.
J Dev Orig Health Dis ; 9(3): 338-343, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29374502

RESUMO

The present study used a sheep model of intrauterine growth restriction, combining maternal undernutrition and twinning, to determine possible markers of early damage to the fetal kidney. The occurrence of early deviations in fetal hemodynamics which may be indicative of changes in blood perfusion was assessed by Doppler ultrasonography. A total of 24 sheep divided in two groups were fed with the same standard grain-based diet but fulfilling either their daily maintenance requirements for pregnancy (control group; n=12, six singleton and six twin pregnancies) or only the 50% of such quantity (food-restricted group; n=12; four singleton and eight twin pregnancies). All the fetuses were assessed by both B-mode and Doppler ultrasonography at Day 115 of pregnancy. Fetal blood supply was affected by maternal undernutrition, although there were still no evidences of brain-sparing excepting in fetuses at greatest challenge (twins in underfed pregnancies). However, there were early changes in the blood supply to the kidneys of underfed fetuses and underfed twins evidenced decreases in kidney size.


Assuntos
Retardo do Crescimento Fetal/fisiopatologia , Hemodinâmica , Nefropatias/etiologia , Desnutrição/complicações , Animais , Animais Recém-Nascidos , Feminino , Nefropatias/diagnóstico por imagem , Nefropatias/patologia , Gravidez , Ovinos , Ultrassonografia Doppler , Ultrassonografia Pré-Natal
2.
Environ Sci Pollut Res Int ; 22(22): 18185-96, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26178827

RESUMO

During the European Life+ project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), photocatalytic remediation of nitrogen oxides (NOx), ozone (O3), volatile organic compounds (VOCs), and airborne particles on photocatalytic cementitious coating materials was studied in an artificial street canyon setup by comparing with a colocated nonactive reference canyon of the same dimension (5 × 5 × 53 m). Although the photocatalytic material showed reasonably high activity in laboratory studies, no significant reduction of NOx, O3, and VOCs and no impact on particle mass, size distribution, and chemical composition were observed in the field campaign. When comparing nighttime and daytime correlation plots of the two canyons, an average upper limit NOx remediation of ≤2% was derived. This result is consistent only with three recent field studies on photocatalytic NOx remediation in the urban atmosphere, whereas much higher reductions were obtained in most other field investigations. Reasons for the controversial results are discussed, and a more consistent picture of the quantitative remediation is obtained after extrapolation of the results from the various field campaigns to realistic main urban street canyon conditions.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Modelos Teóricos , Processos Fotoquímicos , Óxidos de Nitrogênio/análise , Ozônio/análise , Compostos Orgânicos Voláteis/análise
3.
J Environ Manage ; 155: 136-44, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25863437

RESUMO

Within the framework of the European Life+-funded project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), which was aimed at demonstrating the effectiveness of photocatalytic coating materials on a realistic scale, a photocatalytic de-polluting field site was set up in the Leopold II tunnel in Brussels, Belgium. For that purpose, photocatalytic cementitious materials were applied on the side walls and ceiling of selected test sections inside a one-way tunnel tube. This article presents the configuration of the test sections used and the preparation and implementation of the measuring campaigns inside the Leopold II tunnel. While emphasizing on how to implement measuring campaigns under such conditions, difficulties encountered during these extensive field campaigns are presented and discussed. This included the severe de-activation observed for the investigated material under the polluted tunnel conditions, which was revealed by additional laboratory experiments on photocatalytic samples that were exposed to tunnel air. Finally, recommendations for future applications of photocatalytic building materials inside tunnels are given.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Catálise , Emissões de Veículos , Bélgica , Materiais de Construção , Humanos
4.
Theriogenology ; 48(1): 1-10, 1997 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16728102

RESUMO

We summarize here the procedures for nuclear transfer using S-phase cytoplasts and describe a new method for avoiding loss of reconstructed embryos from the oviducts during in vivo culture. We obtained 2 clones of 5 genetically identical animals following the transfer of blastomeres from 16-cell embryos into enucleated preactivated cytoplasts. Metaphase II oocytes and embryos were surgically collected from superovulated Sarda breed ewes 54 and 120 h after sponge removal, respectively. Oocytes were exposed for 15 min to 5 mug/ml of Hoechst 33342 and were micromanipulated at room temperature. Efficiency in embryo reconstruction was 100% for enucleation and 98% for fusion. Embryos were embedded in agar as separate clones and transferred into the oviducts of temporary recipients. The fimbriae were closed with glass-nylon made filters. Embryo recovery from the temporary recipients was 97.3%, with a cleavage rate of 81.4%; development to morula-blastocyst stage was 70.6%. A total of 29 Grade 1 blastocysts corresponding to 5 clones were transferred into 13 naturally synchronous ewes, and scanning was performed at 30 and 90 d. Ten ewes were pregnant at the first scanning and nine at the second for a final pregnancy rate of 71.4%; the survival rate at term was 48%. Overall, we obtained 4 clones of identical lambs: two sets of 5 (one male set and one female set) and two sets of twins (both sets male). Pregnancy length in recipients carrying clones was longer than the standard period in Sarda breed (153 vs 150 d, respectively). Weight at birth was higher for male lambs obtained from nuclear transfer than for normal males (4.1 vs 3.6 kg), while the weight for females was normal.

5.
Theriogenology ; 42(2): 235-9, 1994 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16727530

RESUMO

The effects of a single injection of porcine FSH (pFSH) administered in long acting vehicle on the superovulatory response of milk (Sarda breed) sheep were determined during the anestrous season. The sheep (n=42), synchronized with intravaginal sponges (40 mg fluorogestone acetate -FGA- for 14 d) were submitted 24 h before sponge removal to three different superovulatory treatments. Group 1 (n=16) was treated with a single intramuscular (im) injection of 16 mg of pFHS dissolved in 30 % polyvinylpyrrolidone (PVP); Group 2 (n=12) was injected im with 6, 5, 3 and 2 mg of pFSH every 12 h over 2 d; Group 3 (n=14) was given 800 IU of PMSG and 12 mg of pFSH. All sheep were mated with a fertile ram. Embryos were recovered surgically at Day 7 of sponge removal and graded for the quality according to their morphology. The percentage of good quality embryos recovered was 84% in Group 1, 68% in Group 2 and 77% in Group 3. Data for the onset of estrus, number of corpora lutea (CL), number of unovulated follicles, embryo recovery rate, embryo quality and fertilization rate were recorded for the 3 groups. The onset of estrus, number of CL, number of unovulated follicles, fertilization rate and number of good quality embryos did not differ significantly among the 3 groups. The embryo recovery rate was significantly lower in the group treated with PMSG-FSH (Group 3) than in the 2 other groups. It is concluded that during the anestrous season a single injection im of pFSH results on average in a superovulatory response as good as the more traditional treatments like multiple injections of pFSH and PMSG-pFSH combined.

6.
Boll Soc Ital Biol Sper ; 68(5): 311-4, 1992 May.
Artigo em Italiano | MEDLINE | ID: mdl-1457099

RESUMO

Embryos at 4 cell stage obtained from Sarda ewes superovulated with FSHp (Sigma) were micromanipulated in order to obtain single blastomeres (1/4 E). The 1/4 E have been located randomly in two groups. In the first (Group A n. 30) the 1/4 E have been put back in empty zonae pellucidae; in the second (Group B n. 21) they have been microencapsulated in sodium alginate (1.1%) by dropping cell-alginate solution in a 1.5% CaCl2. Each capsule (1 mm diameter) contained four 1/4 E. The blastomeres have been co-cultured for 5 days in CZB medium on oviductal cell monolayer in a humidified incubator (5% CO2, 95% air, 38.5 degrees C). No differences were found between the groups reaching blastocyst stage after the end of the culture period (A 50%-B 47%).


Assuntos
Alginatos , Blastômeros/fisiologia , Técnicas de Cultura/métodos , Desenvolvimento Embrionário e Fetal/fisiologia , Ovinos/embriologia , Zona Pelúcida/fisiologia , Animais , Composição de Medicamentos , Ácido Glucurônico , Ácidos Hexurônicos , Micromanipulação
7.
Boll Soc Ital Biol Sper ; 66(12): 1173-9, 1990 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-2100529

RESUMO

Four cell embryos collected by laparatomy from Sardinian breed ewes superovulated with FSH-p (16 mg Sigma), were divested of their zonae pellucidae (ZP) by micromanipulation or chemical methods (pronase 0.5%, tyrode pH 2.2). The blastomeres were separated by pipetting using a flame polished pasteur pipette in a Ca free medium (PBS. Sigma) and were inserted into previously evacuated Z.P. using a Leitz micromanipulator. The Z.P. were removed either mechanically or with acid tyrode; pronase was unable to digest them after incubation at 30 degrees C for 120 minutes. The single blastomeres were cocultured on a monolayer of ovine oviductal epithelial cells in TCM 199 + 10 FCS at 38 degrees C in 5% CO2 for 60 hours. No developments were observed in blastomeres obtained by acid digestion of the ZP while 50% of the other blastomeres continued their development until the 16 cell stages. Our results suggest that coculture with oviductal epithelial cell monolayers can support in vitro development of single ovine blastomeres.


Assuntos
Blastômeros , Desenvolvimento Embrionário e Fetal , Técnicas de Cultura de Órgãos/métodos , Ovinos/embriologia , Animais , Células Cultivadas , Embrião de Mamíferos/cirurgia , Células Epiteliais , Oviductos/citologia
8.
Boll Soc Ital Biol Sper ; 65(5): 445-52, 1989 May.
Artigo em Italiano | MEDLINE | ID: mdl-2775549

RESUMO

Ovarian activity, assessed by the plasma progesterone concentrations, were studied in four groups of Sardinian breed sheep with different lambing season. The resumption of ovarian activity was shorter and similarly the proportion of ewes which had resumed ovarian activity in response to introduction of rams was greater in sheep with November and December rather than January and March lambings. The resumption of oestrus activity was delayed in sheep with a high level of lactation.


Assuntos
Ovário/fisiologia , Período Pós-Parto/fisiologia , Ovinos/fisiologia , Animais , Estro , Feminino , Lactação , Gravidez , Progesterona/sangue , Estações do Ano , Comportamento Sexual Animal
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