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21.
This work represents the first attempt to define tardigrade chromosomes using banding techniques. Macrobiotus richtersi, a eutardigrade morphospecies with amphimictic diploid and thelytokous triploid cytotypes, was used as a model. Prime consideration
was given to oocyte chromosomes because they are larger than those of spermatocytes and of mitotic chromosomes. With Giemsa
staining, the chromatids of the 6 bivalents of the diploid cytotypes and those of the 17–18 univalents of the triploid cytotypes
were very similar to each other and appeared rod- or flame-shaped. In the amphimictic strain, a chiasma was generally present
in each bivalent at diplotene, whereas there were no chiasmata in the oocyte prophase chromosomes of the triploid strain.
Both in diploid and triploid cytotypes, C-banding and fluorescence showed a heterochromatic centromeric band on the telomere
of each chromosome oriented towards the spindle pole, indicating that all of them were acrocentric. Silver staining showed
the presence of a NOR in only a pair of chromosomes, close to the centromeric C-banded site. NOR was particularly evident
in the oocyte prophases. Other silver positive regions, corresponding to the kinetochore, were located on all other chromosomes
on the telomeres towards the spindle pole.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
22.
Molina MC Ferreira V Valck C Aguilar L Orellana J Rojas A Ramirez G Billetta R Schwaeble W Lemus D Ferreira A 《Molecular and biochemical parasitology》2005,140(2):133-140
Angiogenesis leads to neovascularization from existing blood vessels. It is associated with tumor growth and metastasis and is regulated by pro- and antiangiogenic molecules, some of them currently under clinical trials for cancer treatment. During the last few years we have cloned, sequenced and expressed a Trypanosoma cruzi calreticulin gene (TcCRT). Its product, TcCRT, a 45 kDa protein, is more than 50% identical to human CRT (HuCRT). TcCRT, present on the surface of trypomastigotes, binds both C1q and mannan binding lectin and inhibits the classical activation pathway of human complement. Since TcCRT is highly homologous to a functional antiangiogenic fragment from HuCRT (aa 120–180), recombinant (r) and native (n) TcCRT were tested in their antiangiogenic effects, in the chick embryonic chorioallantoid membrane (CAM) assay. Both proteins mediated highly significant antiangiogenic effects in the in vivo CAM assay. This effect was further substantiated in experiments showing that the plasmid construct pSecTag/TcCRT also displayed significant antiangiogenic properties, as compared to the empty vector. Most likely, the fact that antiangiogenic substances act preferentially on growing neoplasic tissues, but not on already established tumors, is due to their effects on emerging blood vessels. The results shown here indicate that TcCRT, like its human counterpart, has antiangiogenic properties. These properties may explain, at least partly, the reported antineoplasic effect of experimental T. cruzi infection. 相似文献
23.
Since one of the greatest reservoirs of allergens is the blanket, we assessed mite allergen levels in dust collected from five blankets by vacuuming before and after dry cleaning with perchlorethylene and compared the results with five control blankets. Assays with monoclonal antibodies showed that group I ( Der p I and Der f I) mite allergen levels per g dust were 78%, lower after dry cleaning. Group 1 allergen levels per m2 of dry-cleaned blankets were 98% lower. RAST inhibition showed that total allergen levels decreased 70% after dry cleaning. Mite allergens were not denatured by perchlorethylene. The effect of dry cleaning resulted from physical washing out of dust and allergens. 相似文献
24.
Lorena Villalba-Heredia Cristina Comeras-Chueca Alejandro Gonzlez-Agüero Daniel Domingo-del-Val Pilar Calmarza Germn Vicente-Rodríguez Jos A. Casajús ngel Matute-Llorente 《Nutrients》2021,13(5)
Childhood obesity has become a major global health problem. Vitamin D deficiency and poor cardiorespiratory fitness are highly prevalent in children with overweight or obesity, but little is known about their relationships. In this study, we aimed to analyze the relationship between serum 25-hydroxyvitamin D (25(OH)D) and cardiorespiratory fitness parameters in prepubertal obese and overweight children. A cross-sectional design with a sample of 57 prepubertal children, aged 9–11 years, with overweight or obesity was used. The fasting concentration of 25(OH)D was analyzed with a chemiluminescent microparticle immunoassay. Fat and lean body masses were determined by using DXA. Maximal oxygen uptake (VO2max) was measured with the maximal treadmill test. A total of 68.4% of the sample had sufficient levels of 25(OH)D. As expected, their cardiorespiratory fitness was poor compared with that of normal-weight children, but 60% of the group exceeded the median obesity-specific reference values. No differences were found between the sexes for relative VO2max or 25(OH)D levels. Moreover, no correlations were found between 25(OH)D and body composition or cardiorespiratory parameters for sex or vitamin D groups. Vitamin D status seems not to be directly related to body composition or cardiorespiratory fitness in prepubertal overweight or obese children. 相似文献
25.
Judit Companys Maria Jos Gosalbes Laura Pla-Pag Lorena Caldern-Prez Elisabet Llaurad Anna Pedret Rosa Maria Valls Nuria Jimnez-Hernndez Berner Andre Sandoval-Ramirez Josep Maria del Bas Antoni Caimari Laura Rubi Rosa Sol 《Nutrients》2021,13(6)
We aimed to differentiate gut microbiota composition of overweight/obese and lean subjects and to determine its association with clinical variables and dietary intake. A cross-sectional study was performed with 96 overweight/obese subjects and 32 lean subjects. Anthropometric parameters were positively associated with Collinsella aerofaciens, Dorea formicigenerans and Dorea longicatena, which had higher abundance the overweight/obese subjects. Moreover, different genera of Lachnospiraceae were negatively associated with body fat, LDL and total cholesterol. Saturated fatty acids (SFAs) were negatively associated with the genus Intestinimonas, a biomarker of the overweight/obese group, whereas SFAs were positively associated with Roseburia, a biomarker for the lean group. In conclusion, Dorea formicigenerans, Dorea longicatena and Collinsella aerofaciens could be considered obesity biomarkers, Lachnospiraceae is associated with lipid cardiovascular risk factors. SFAs exhibited opposite association profiles with butyrate-producing bacteria depending on the BMI. Thus, the relationship between diet and microbiota opens new tools for the management of obesity. 相似文献
26.
27.
Robison Valerie Bauman Brenda D’Angelo Denise V. Espinoza Lorena Thornton-Evans Gina Lin Mei 《Maternal and child health journal》2021,25(5):832-840
Maternal and Child Health Journal - To measure the association between dental and medical insurance with the receipt of dental cleaning during pregnancy. We analyzed Pregnancy Risk Assessment... 相似文献
28.
Evangelista André Nobre dos Santos Flávia Franciele de Oliveira Martins Lorena Pacheco Gaiad Thais Peixoto Machado Alex Sander Dias Rocha-Vieira Etel Costa Karine Beatriz Santos Ana Paula Oliveira Murilo Xavier 《Lasers in medical science》2021,36(6):1201-1208
Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in... 相似文献
29.
Tania Lorena Mcwilliams Di Twigg Joyce Hendricks Fiona Melanie Wood Jane Ryan Anthony Keil 《Burns : journal of the International Society for Burn Injuries》2021,47(3):569-575
AimTo evaluate the impact of the implementation of a best practice infection prevention and control bundle on healthcare associated burn wound infections in a paediatric burns unit.BackgroundBurn patients are vulnerable to infection. For this patient population, infection is associated with increased morbidity and mortality, thereby representing a significant challenge for burns clinicians who care for them.MethodsAn interrupted time series was used to compare healthcare associated burn wound infections in paediatric burn patients before and after implementation of an infection prevention and control bundle. Prospective surveillance of healthcare associated burn wound infections was conducted from 2012 to 2014. Other potential healthcare associated infection rates were also reviewed over the study period, including urinary tract infections, pneumonia, upper respiratory tract infections and sepsis. An infection prevention and control bundle developed in collaboration between the paediatric burn unit and infection control clinicians was implemented in 2013 in addition to previous standard practice.ResultsDuring the study period a total of 626 patients were admitted to the paediatric burns unit. Healthcare associated burn wound infections reduced from 34 in 2012 to 0 in 2014 following the implementation of the infection prevention and control bundle. Pneumonia and sepsis also reduced to 0 in 2013 and 2014, however one upper respiratory tract infection occurred in 2013 and urinary tract infections persisted in 2013.ConclusionThe implementation of an infection prevention and control bundle was effective in reducing healthcare associated burn wound infections, pneumonia and sepsis within our paediatric burns unit. Urinary tract infections remain a challenge for future improvement. 相似文献
30.