Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Genetic polymorphisms in the 3′UTR region of the CXCL12 (rs1801157) and TP53 codon 72 (rs1042522) genes may contribute to susceptibility to childhood ALL because they affect some important processes, such as metastasis regulation and tumor suppression. Thus the objective of the present study was to detect the frequency of two genetic polymorphisms in ALL patients and controls and to add information their impact on genetic susceptibility and prognosis. The CXCL12 and TP53 polymorphisms were tested in 54 ALL child patients and in 58 controls by restriction fragment length polymerase chain reaction and allelic specific chain reaction techniques, respectively. The frequencies of both allelic variants were higher in ALL patients than in the controls and indicated a positive association: OR = 2.44; 95 % CI 1.05–5.64 for CXCL12 and OR = 2.20; 95 % CI 1.03–4.70 for TP53. Furthermore, when the two genetic variants were analyzed together, they increased significantly more than fivefold the risk of this neoplasia development (OR = 5.24; 95 % CI 1.39–19.75), indicating their potential as susceptibility markers for ALL disease and the relevance of the allelic variant combination to increased risk of developing malignant tumors. Future studies may indicate a larger panel of genes involved in susceptibility of childhood ALL and other hematological neoplasias. 相似文献
Coagulase-negative staphylococci (CoNS) are the microorganisms most frequently isolated from clinical samples and are commonly found in neonatal blood cultures. Oxacillin is an alternative treatment of choice for CoNS infections; however, resistance to oxacillin can have a substantial impact on healthcare by adversely affecting morbidity and mortality. The objective of this study was to detect and characterise oxacillin-resistant CoNS strains in blood cultures of newborns hospitalised at the neonatal ward of the University Hospital of the Faculty of Medicine of Botucatu. One hundred CoNS strains were isolated and the mecA gene was detected in 69 of the CoNS strains, including 73.2% of Staphylococcus epidermidis strains, 85.7% of Staphylococcus haemolyticus strains, 28.6% of Staphylococcus hominis strains and 50% of Staphylococcus lugdunensis strains. Among these oxacillin-resistant CoNS strains, staphylococcal cassette chromosome mec (SCCmec) type I was identified in 24.6%, type II in 4.3%, type III in 56.5% and type IV in 14.5% of the strains. The data revealed an increase in the percentage of CoNS strains isolated from blood cultures from 1991-2009. Furthermore, a predominant SCCmec profile of the oxacillin-resistant CoNS strains isolated from neonatal intensive care units was identified with a prevalence of SCCmec types found in hospital-acquired strains. 相似文献
A modified version of amarantin, main seed storage protein of Amaranthushypochondriacus, carrying four antihypertensive biopeptides Val-Tyr into the acidic-subunit of the protein, was expressed in cell suspension cultures of Nicotiana tabacum L. NT1. Cell growth and viability kinetics were assessed to determine optimal conditions for genetic transformation via Agrobacterium tumefaciens. Selection of putative transgenic calli was conducted using 25 μg ml?1 hygromycin. Presence of the transgene was confirmed using histological glucuronidase assay and PCR analysis. Accumulation and expression of the recombinant protein was detected using Western blot analysis. Protein hydrolysate of transgenic calli showed high levels of inhibition of the angiotensin converting enzyme, with an IC50 value of 3.5 μg ml?1. This was 10-fold lower than that of protein extracts of wild-type cells, with an IC50 of 29.0 μg ml?1. 相似文献
A thermotolerant fungus identified as Aspergillus niveus was isolated from decomposing materials and it has produced excellent levels of hydrolytic enzymes that degrade plant cell walls. A. niveus germinated faster at 40 °C, presenting protein levels almost twofold higher than at 25 °C. The crude extract of the A. niveus culture was purified by diethylaminoethyl (DEAE)-cellulose, followed by Biogel P-100 column. Polygalacturonase (PG) is a glycoprotein with 37.7 % carbohydrate, molecular mass of 102.6 kDa, and isoelectric point of 5.4. The optimum temperature and pH were 50 °C and 4.0–6.5, respectively. The enzyme was stable at pH 3.0 to 9.0 for 24 h. The DEAE-cellulose derivative was about sixfold more stable at 60 °C than the free enzyme. Moreover, the monoaminoethyl-N-aminoethyl-agarose derivative was tenfold more stable than the free enzyme. PG was 232 % activated by Mn2+. The hydrolysis product of sodium polypectate corresponded at monogalacturonic acid, which classifies the enzyme as an exo-PG. The Km, Vmax, Kcat, and Kcat/Km values were 6.7 mg/ml, 230 U/mg, 393.3/s, and 58.7 mg/ml/s, respectively. The N-terminal amino acid sequence presented 80 % identity with PglB1, PglA2, and PglA3 putative exo-PG of Aspergillus fumigatus and an exo-PG Neosartorya fischeri. 相似文献
The diverse pollen morphology of fourteen species of the genus Eperua is described and illustrated using light, scanning electron and transmission electron microscopy. Six pollen types are described and a key for their identification is provided. A cladistic analysis was carried out using macromorphological and palynological characters to form a hypothesis of relationships between taxa. The pollen morphology is discussed with regard to systematic relationships, function and phylogenetic significance of certain pollen morphological structures within the genus. 相似文献
In light of climate change and risks of food insecurity, it is becoming increasingly important to preserve plant germplasm in genebanks. Storage of seeds, particularly via cryopreservation, is one of the most proficient methods for ex situ plant germplasm conservation. Whilst seed cryo-banking can have little, to no, or even beneficial effects on subsequent seedling vigor in some species, it can lead to a number of plant abnormalities (morphological and physiological). This study investigated the effects of maize seed cryopreservation on seedling growth (until 14 d) and levels of selected amino acids produced in the shikimate pathway, a major link between primary and secondary metabolism. Seed cryopreservation reduced FW in recovered seedlings, reduced caffeic acid (2.5-fold decrease), and increased levels of all other shikimate pathway–related compounds assessed: phenylalanine (2.9-fold increase), tyrosine (2.6-fold increase), and shikimic (2.1-fold increase) and protocathecuic (3.1-fold increase) acids in cotyledons. Our results suggest that maize seed cryopreservation results in seedlings that exhibit signs of an ‘overly’ efficient and caffeic acid–deficient shikimate pathway, possibly related to their reduced growth during a highly vulnerable growth stage. However, these metabolic abnormalities manifested most severely in the maternal (cotyledonary), as opposed to vegetative (roots, stems, and leaves), tissues and hence are likely to disappear when the seedlings shed the cotyledons and become completely autotrophic.
During the induction process of an in vitro callus culture of Argemone mexicana L. (Papaveraceae), the levels of two benzylisoquinoline alkaloids known as berberine and sanguinarine displayed opposing trends. While the berberine levels steadily decreased from the initial explant stage up to the early proliferation of unorganized parenchymatous cell masses, the sanguinarine content increased. Once the callus culture was established, sanguinarine was the primary alkaloid present and berberine could no longer be detected. However, upon shoot regeneration, the berberine accumulation recovered, but sanguinarine was found in the newly formed leafy tissue. After root formation, sanguinarine was relocated to this organ, whereas berberine was evenly distributed between both tissues. Explants from stem internodes did not form callus, and berberine—plus sanguinarine—containing axillary shoots emerged from lateral buds in the induction medium. In contrast to callus-derived shoots, no root formation was observed. Therefore, alkaloid synthesis in A. mexicana in vitro cultures is related to the level of tissue organization in different ways, and while berberine accumulation seems to require the presence of differentiated organs, this is not the case for sanguinarine. Moreover, leafy parts of rootless shoots acquired the capacity to accumulate sanguinarine, which is usually absent in aerial tissues of mature plants. However, when these shoots were rooted, sanguinarine was mainly located in the newly formed roots, while berberine was detected in the shoots at similar levels found in the roots.
Objective: Visfatin has shown to be increased in obesity and in type 2 diabetes. The aim of this study was to determine the change in plasma visfatin in severely obese (SO) persons after weight loss following bariatric surgery in relation to glucose concentration. Research Methods and Procedures: Visfatin and leptin were studied in 53 SO persons (BMI, 54.4 ± 6.8 kg/m2) before and 7 months after bariatric surgery and in 28 healthy persons (BMI, 26.8 ± 3.8 kg/m2). All of the patients underwent bariatric surgery with biliopancreatic diversion or gastric bypass. Results: The pre‐surgery levels of visfatin in the SO group were greater than in the control group (55.9 ± 39.9 vs. 42.9 ± 16.6 ng/mL, p = 0.024). This increase was significant in the SO group with impaired fasting glucose (63.4 ± 36.6 ng/mL) and diabetes (60.0 ± 46.0 ng/mL). SO patients with normal fasting glucose had similar levels of visfatin to the controls. Seven months after surgery, visfatin levels were significantly increased (84.8 ± 32.8 ng/mL, p < 0.001). This increase was independent of the pre‐surgical glucose levels. The type of bariatric surgery had no influence on visfatin levels. Post‐surgical visfatin was significantly correlated with the post‐surgery plasma concentrations of leptin (r = 0.39, p = 0.014). Discussion: Plasma levels of visfatin in the SO group were increased but only when accompanied by high glucose levels, even in the range of impaired fasting glucose. Bariatric surgery causes an increase in visfatin, which is correlated mainly with the changes produced in the leptin concentration. 相似文献