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21.
Alessandro S Guimarães Filipe B Carmo Marcos B Heinemann Ricardo WD Portela Roberto Meyer Andrey P Lage Núbia Seyffert Anderson Miyoshi Vasco Azevedo Aurora MG Gouveia 《BMC veterinary research》2011,7(1):1-5
Background
Multiple congenital ocular anomalies (MCOA) syndrome is a hereditary congenital eye defect that was first described in Silver colored Rocky Mountain horses. The mutation causing this disease is located within a defined chromosomal interval, which also contains the gene and mutation that is associated with the Silver coat color (PMEL17, exon 11). Horses that are homozygous for the disease-causing allele have multiple defects (MCOA-phenotype), whilst the heterozygous horses predominantly have cysts of the iris, ciliary body or retina (Cyst-phenotype). It has been argued that these ocular defects are caused by a recent mutation that is restricted to horses that are related to the Rocky Mountain Horse breed. For that reason we have examined another horse breed, the Icelandic horse, which is historically quite divergent from Rocky Mountain horses.Results
We examined 24 Icelandic horses and established that the MCOA syndrome is present in this breed. Four of these horses were categorised as having the MCOA-phenotype and were genotyped as being homozygous for the PMEL17 mutation. The most common clinical signs included megaloglobus, iris stromal hypoplasia, abnormal pectinate ligaments, iridociliary cysts occasionally extending into the peripheral retina and cataracts. The cysts and pectinate ligament abnormalities were observed in the temporal quadrant of the eyes. Fourteen horses were heterozygous for the PMEL17 mutation and were characterized as having the Cyst-phenotype with cysts and occasionally curvilinear streaks in the peripheral retina. Three additional horses were genotyped as PMEL17 heterozygotes, but in these horses we were unable to detect cysts or other forms of anomalies. One eye of a severely vision-impaired 18 month-old stallion, homozygous for the PMEL17 mutation was examined by light microscopy. Redundant duplication of non-pigmented ciliary body epithelium, sometimes forming cysts bulging into the posterior chamber and localized areas of atrophy in the peripheral retina were seen.Conclusions
The MCOA syndrome is segregating with the PMEL17 mutation in the Icelandic Horse population. This needs to be taken into consideration in breeding decisions and highlights the fact that MCOA syndrome is present in a breed that are more ancient and not closely related to the Rocky Mountain Horse breed. 相似文献22.
Recent approaches have failed to detect nucleotide sequence motifs in Scaffold/Matrix Attachment Regions (S/MARs). The lack
of any known motifs, together with the confirmation that some S/MARs are not associated to any peculiar sequence, indicates
that some structural elements, such as DNA curvature, have a role in chromatin organization and on their efficiency in protein
binding. Similar to DNA curvature, S/MARs are located close to promoters, replication origins, and multiple nuclear processes
like recombination and breakpoint sites. The chromatin structure in these regulatory regions is important to chromosome organization
for accurate regulation of nuclear processes. In this article we review the biological importance of the co-localization between
bent DNA sites and S/MARs.
Published in Russian in Biokhimiya, 2006, Vol. 71, No. 5, pp. 598–606. 相似文献
23.
Z Carvalho-Santos P Machado I Alvarez-Martins SM Gouveia SC Jana P Duarte T Amado P Branco MC Freitas ST Silva C Antony TM Bandeiras M Bettencourt-Dias 《Developmental cell》2012,23(2):412-424
Cilia and flagella are involved in a variety of processes and human diseases, including ciliopathies and sterility. Their motility is often controlled by?a central microtubule (MT) pair localized within the ciliary MT-based skeleton, the axoneme. We characterized the formation of the motility apparatus in detail in Drosophila spermatogenesis. We show that assembly of the central MT pair starts prior to the meiotic divisions, with nucleation of a singlet MT within the basal body of a small cilium, and that the second MT of the pair only assembles much later, upon flagella formation. BLD10/CEP135, a conserved player in centriole and flagella biogenesis, can bind and stabilize MTs and is required for the early steps of central MT pair formation. This work describes a genetically tractable system to study motile cilia formation and provides an explanation for BLD10/CEP135's role in assembling highly stable MT-based structures, such as motile axonemes and centrioles. 相似文献
24.
EM Dorneles JA Santana GI Andrade EL Santos AS Guimarães RA Mota AS Santos A Miyoshi V Azevedo AM Gouveia AP Lage MB Heinemann 《Genetics and molecular research : GMR》2012,11(3):2051-2059
Corynebacterium pseudotuberculosis, the infectious agent of caseous lymphadenitis (CLA), is responsible for substantial economic losses in goat and sheep production. Molecular characterization of C. pseudotuberculosis isolates by enterobacterial repetitive intergenic consensus (ERIC)-PCR has shown promising results in genotyping strains isolated from sheep with CLA. We evaluated the genetic diversity of C. pseudotuberculosis isolates collected from the Sert?o region of the Pernambuco (PE) State, Brazil, and investigated the potential of ERIC-PCR as a tool for the molecular typing of strains of C. pseudotuberculosis isolated from goats. Thirty-two C. pseudotuberculosis strains isolated from goats in the municipalities of Floresta and Ibimirim, PE, C. pseudotuberculosis type strain ATCC 19410, the 1002 vaccine strain, and a field isolate of Rhodococcus equi were fingerprinted using the primers ERIC-1R and ERIC-2 and the primer pair ERIC- 1R+ERIC-2. Using 100% similarity as the cutoff, 8, 10, and 7 genotypes were obtained with ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively. The Hunter-Gaston discriminatory index calculated for the ERIC-1-PCR was 0.75. The index for the ERIC-2-PCR was 0.88, and the index for the ERIC-1+2-PCR was 0.79. Among goat isolates of C. pseudotuberculosis, three, two and four genotypes (found by ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively) had been previously described among sheep isolates from Minas Gerais State, Brazil. These results showed that ERIC-PCR has good discriminatory power and typeability, making it a useful tool for discrimination among C. pseudotuberculosis isolates from goats. 相似文献
25.
L M Gouveia G M Paccola M T Torquato F O Menezes C E Piccinato M C Foss 《Hormones et métabolisme》2000,32(1):35-39
The present study was designed to determine the effect of essential hypertension on peripheral glucose metabolism during the postabsorptive state and after an oral glucose challenge. Ten normal subjects and nine patients with essential hypertension were studied after an overnight fast (12-14 h) and for 3 h after the ingestion of 75 g of glucose. Peripheral glucose metabolism was analyzed by the forearm technique to estimate muscle exchange of substrate combined with indirect calorimetry. Decreased forearm glucose uptake was observed in hypertensive patients compared to normal subjects (4.9+/-0.6 vs. 8.6+/-0.5 mmol x 100 ml forearm(-1) x 3 h(-1)) with diminished nonoxidative glucose metabolism (2.7+/-0.5 vs. 6.9+/-0.6 mmol x 100 ml forearm(-1) x 3 h(-1)). Muscle glucose oxidation did not differ significantly between groups. Both serum free fatty acid levels and lipid oxidation rates were similar in the normal subjects and the hypertensive patients, and declined in a similar fashion after glucose ingestion. Basal serum insulin levels did not differ significantly between normal and hypertensive patients, whereas the insulinemic response to glucose load was greater among the patients with essential hypertension. These data show that insulin resistance occurring in patients with essential hypertension is accompanied by impaired muscle glucose uptake and nonoxidative metabolism. 相似文献
26.
EO Ogueji CD Nwani SC Iheanacho CE Mbah CO Okeke A Yaji 《African Journal of Aquatic Science》2018,43(3):293-303
Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled. 相似文献
27.
Leonilde Marchão Teresa Lopes da Silva Luísa Gouveia Alberto Reis 《Journal of applied phycology》2018,30(3):1583-1595
Microalgae have been used to remove nitrogen, phosphorus, and chemical oxygen demand (COD) from brewery wastewater (BWW). The microalga Scenedesmus obliquus was grown on BWW, using bubble column photobioreactors that operated under batch and continuous regimes. For the first time, the cell physiological status cell membrane integrity and enzymatic activity was monitored during the microalgae based BWW treatment, using flow cytometry. All the cultivations batch and continuous displayed a proportion of cells with intact membrane >?87%, although the continuous cultivations displayed a lower proportion of cells with enzymatic activity (20–40%) than the batch cultivations (97%). The dilution rate of 0.26 day?1 was the most favorable condition, since the microalgae cultivation attained the maximum biomass productivity (0.2 g ash-free dry weight day?1) and the total nitrogen and COD removal rates were the highest (97 and 74%, respectively), while the phosphorous removal rate was the third (23%). 相似文献
28.
Context-dependent memory: colour versus odour 总被引:2,自引:1,他引:1
An olfactory stimulus and a visual stimulus were employed in a context-
dependent memory study using a prose passage as the to-be-remembered item.
Ninety-five university students (aged 17-35 years) learned the passage of
prose in the presence of one of the stimuli and were then asked to recall
the passage with the original context either reinstated or not reinstated.
The results revealed a significant context-dependent memory effect for the
olfactory cue but not for the visual cue. They demonstrate support for the
effectiveness of odours as context cues and it is suggested that
context-dependent memory processes may underlie the formation and retrieval
of odour-evoked autobiographical memories.
相似文献
29.
30.