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61.
Alomá Moreno O y MJ Freuler 《Phyton》2015,84(2):466-472
The present study of the Orchidaceae family was carried out in Guamuahaya’s mountain range, from 2000 to March 2013. Fifteen districts were explored after 33 expeditions in the Province of Cienfuegos. Ninety two plant species were identified in the studied area, taking into account the ecological parameters of the mountainous areas of Cienfuegos and Cumanayagua municipalities. 相似文献
62.
MJ Doughty 《Biotechnic & histochemistry》2016,91(8):501-509
Goblet cells were visualized in impression cytology specimens from bulbar conjunctiva of the rabbit eye using Giemsa staining. Highly magnified images were used to generate outlines of the goblet cells and their characteristic eccentric nuclei. Using sets of 10 cells from 15 cytology specimens, I found that the longest dimension of the goblet cells averaged 16.7 ± 2.3 μm, the shortest dimension averaged 14.4 ± 1.8 μm and the nucleus averaged 6.3 ± 0.8 μm. The goblet cells were ellipsoid in shape and the longest:shortest cell dimension ratio averaged 1.169 ± 0.091. The goblet cell areas ranged from 108 to 338 μm2 (average 193 ± 50 μm2). The area could be predicted reliably from the longest and shortest dimensions (r2 = 0.903). The areas of goblet cell nuclei were 15–58 μm2 (average 33 ± μm2) and the nucleus:cytoplasm area fraction was predictably greater in smaller goblet cells and less in the larger goblet cells (Spearman correlation = 0.817). The nuclei were estimated to occupy an average of 9.5% of the cell volume. The differences in size, shape and nucleus:cytoplasm ratio may reflect differences in goblet cell maturation. 相似文献
63.
The suitability of using macroinvertebrates as bioindicators of stream water quality was tested in the Mkondoa River in an agricultural area at Kilosa, using the rapid bioassessment protocol. The family biotic index (FBI) showed marked variation in water quality along the stream from values ranging from 4.1 to 5.0 in the upstream reaches, indicating good water quality, 5.3 to 5.5 in the mid-reaches and 6.0 to 6.5 in the lower reaches. The water quality index (WQI) indicated that water quality was fair (77 ± 0.98) in the upstream reach of the Mkondoa, marginal (55 ± 0.86) in the midstream reach and poor (33 ± 0.45) in the downstream reach. There were significant relationships between biological oxygen demand and dissolved oxygen and the occurrence of specific taxa, mainly Chironomus and Caenis. Significant changes in macroinvertebrate abundance were mostly related to changes in water quality. As in other parts of the world, macroinvertebrate communities proved to be good biological indicators of water quality and they should be used as bioindicators in long-term monitoring of this river. 相似文献
64.
Susan C Burleigh Teun van de Laar Corné JM Stroop Wout MJ van Grunsven Niaobh O’Donoghue Pauline M Rudd Gavin P Davey 《BMC biotechnology》2011,11(1):1-17
Background
The photorespiratory nitrogen cycle in C3 plants involves an extensive diversion of carbon and nitrogen away from the direct pathways of assimilation. The liberated ammonia is re-assimilated, but up to 25% of the carbon may be released into the atmosphere as CO2. Because of the loss of CO2 and high energy costs, there has been considerable interest in attempts to decrease the flux through the cycle in C3 plants. Transgenic tobacco plants were generated that contained the genes gcl and hyi from E. coli encoding glyoxylate carboligase (EC 4.1.1.47) and hydroxypyruvate isomerase (EC 5.3.1.22) respectively, targeted to the peroxisomes. It was presumed that the two enzymes could work together and compete with the aminotransferases that convert glyoxylate to glycine, thus avoiding ammonia production in the photorespiratory nitrogen cycle.Results
When grown in ambient air, but not in elevated CO2, the transgenic tobacco lines had a distinctive phenotype of necrotic lesions on the leaves. Three of the six lines chosen for a detailed study contained single copies of the gcl gene, two contained single copies of both the gcl and hyi genes and one line contained multiple copies of both gcl and hyi genes. The gcl protein was detected in the five transgenic lines containing single copies of the gcl gene but hyi protein was not detected in any of the transgenic lines. The content of soluble amino acids including glycine and serine, was generally increased in the transgenic lines growing in air, when compared to the wild type. The content of soluble sugars, glucose, fructose and sucrose in the shoot was decreased in transgenic lines growing in air, consistent with decreased carbon assimilation.Conclusions
Tobacco plants have been generated that produce bacterial glyoxylate carboligase but not hydroxypyruvate isomerase. The transgenic plants exhibit a stress response when exposed to air, suggesting that some glyoxylate is diverted away from conversion to glycine in a deleterious short-circuit of the photorespiratory nitrogen cycle. This diversion in metabolism gave rise to increased concentrations of amino acids, in particular glutamine and asparagine in the leaves and a decrease of soluble sugars. 相似文献65.
Zuluaga NA Cuartas JM Londoño JG 《Biomédica : revista del Instituto Nacional de Salud》2004,24(2):207-225
Due to its high prevalence during pregnancies, preeclampsia is considered an important public health problem. Many investigators agree in that its expression is related to the interaction between genetic and environmental factors. Many studies have searched for genetic factors, attempting to identify chromosomal regions or candidate genes whose variants may be related to high preeclampsia susceptibility. Several studies have associated a number of susceptibility genes to preeclampsia, but the results have not been replicated consistently in all populations. Mapping of genes and chromosomal regions by linkage analysis has located potential markers on chromosomes 2 and 4. Identification of the genes located in these candidate regions will pinpoint the genetic risk factors, will lead to a better understanding of the syndrome, and will provide clues for its prevention and treatment. 相似文献
66.
67.
A Luquita L Urli MJ Svetaz AM Gennaro ME Giorgetti G Pistone R Volpintesta S Palatnik M Rasia 《Journal of biomedical science》2010,17(1):8
Background
Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology. 相似文献68.
Yurany Granada Ana María Mejía-Jaramillo Sara Zuluaga Omar Triana-Chvez 《PLoS neglected tropical diseases》2021,15(12)
IntroductionIn Colombia, organochloride, organophosphate, carbamate, and pyrethroid insecticides are broadly used to control Aedes aegypti populations. However, Colombian mosquito populations have shown variability in their susceptibility profiles to these insecticides, with some expressing high resistance levels.Materials and methodsIn this study, we analyzed the susceptibility status of ten Colombian field populations of Ae. aegypti to two pyrethroids; permethrin (type-I pyrethroid) and lambda-cyhalothrin (type-II pyrethroid). In addition, we evaluated if mosquitoes pressured with increasing lambda-cyhalothrin concentrations during some filial generations exhibited altered allelic frequency of these kdr mutations and the activity levels of some metabolic enzymes.ResultsMosquitoes from all field populations showed resistance to lambda-cyhalothrin and permethrin. We found that resistance profiles could only be partially explained by kdr mutations and altered enzymatic activities such as esterases and mixed-function oxidases, indicating that other yet unknown mechanisms could be involved. The molecular and biochemical analyses of the most pyrethroid-resistant mosquito population (Acacías) indicated that kdr mutations and altered metabolic enzyme activity are involved in the resistance phenotype expression.ConclusionsIn this context, we propose genetic surveillance of the mosquito populations to monitor the emergence of resistance as an excellent initiative to improve mosquito-borne disease control measures. 相似文献
69.
E Martinez-Jaramillo R Garza-Morales MJ Loera-Arias O Saucedo-Cardenas R Montes-de-Oca-Luna LR McNally 《Biotechnic & histochemistry》2017,92(3):167-174
Fluorescent proteins are useful reporter molecules for a variety of biological systems. We present an alternative strategy for cloning reporter genes that are regulated by the nisin-controlled gene expression (NICE) system. Lactoccocus lactis was genetically engineered to express green fluorescent protein (GFP), mCherry or near-infrared fluorescent protein (iRFP). The reporter gene sequences were optimized to be expressed by L. lactis using inducible promoter pNis within the pNZ8048 vector. Expression of constructions that carry mCherry or GFP was observed by fluorescence microscopy 2 h after induction with nisin. Expression of iRFP was evaluated at 700 nm using an infrared scanner; cultures induced for 6 h showed greater iRFP expression than non-induced cultures or those expressing GFP. We demonstrated that L. lactis can express efficiently GFP, mCherry and iRFP fluorescent proteins using an inducible expression system. These strains will be useful for live cell imaging studies in vitro or for imaging studies in vivo in the case of iRFP. 相似文献
70.
T-helper 17 cell cytokines and interferon type I: partners in crime in systemic lupus erythematosus?
Zana Brkic Odilia BJ Corneth Cornelia G van Helden-Meeuwsen Radboud JEM Dolhain Naomi I Maria Sandra MJ Paulissen Nadine Davelaar Jan Piet van Hamburg Paul L van Daele Virgil A Dalm P Martin van Hagen Johanna MW Hazes Marjan A Versnel Erik Lubberts 《Arthritis research & therapy》2014,16(2):R62