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91.
A complex relationship links magnesium and cancer. The aim of this review is to revisit current knowledge concerning the contribution of magnesium to tumorigenesis, from transformed cells to animal models, and ending with data from human studies. Cultured neoplastic cells tend to accumulate magnesium. High intracellular levels of the cation seem to confer a metabolic advantage to the cells, contribute to alterations of the genome, and promote the acquisition of an immortal phenotype. In magnesium-deficient mice, low magnesium both limits and fosters tumorigenesis, since inhibition of tumor growth at its primary site is observed in the face of increased metastatic colonization. Epidemiological studies identify magnesium deficiency as a risk factor for some types of human cancers. In addition, impaired magnesium homeostasis is reported in cancer patients, and frequently complicates therapy with some anti-cancer drugs. More studies should be undertaken in order to disclose whether a simple and inexpensive intervention to optimize magnesium intake might be helpful in the prevention and treatment of cancer. 相似文献
92.
Lapolla A Dalfrà MG Bonomo M Castiglioni MT Di Cianni G Masin M Mion E Paleari R Schievano C Songini M Tocco G Volpe L Mosca A 《Diabetes research and clinical practice》2007,77(3):465-470
To assess whether HbA1c and plasma glucose predicts abnormal fetal growth, 758 pregnant women attending 5 Diabetic Centers were screened for gestational diabetes mellitus (GDM). On glucose challenge (GCT) at 24-27 weeks of gestation (g.w.), negative cases formed the normal control group (N1). Positive cases took an oral glucose tolerance test (OGTT): those found negative were classed as false positives screening test (N2); if they had an OGTT result at least as high as their normal glucose levels, they were classed as having one abnormal glucose value (OAV) at OGTT; two values as GDM. HbA1c was assayed on the day of GCT. We considered fetal macrosomia, large for gestational age (LGA), ponderal index and mean growth percentile. Mean age, pre-pregnancy BMI, fasting plasma glucose (FPG) and HbA1c were progressively higher from N1 to GDM patients. The newborn of N2 mothers were heavier than those with N1 or GDM. The mean growth percentile was significantly higher in N2 than in N1. More LGA babies were born to OAV than to N1 or N2 women. Macrosomia and ponderal index did not differ significantly in the four groups. At logistic regression only plasma glucose at GCT could predict LGA babies and a ponderal index above 2.85. At risk analysis, GDM and OAV significantly predicted LGA babies, and GDM a ponderal index >2.85. In conclusion, FPG at GCT could predict fetal overgrowth and plasma glucose >85mg/dl doubles the risk of LGA infants. HbA1c at 24-27g.w. does not predict fetal overgrowth. Mild alterations in glucose tolerance correlate with fetal overgrowth and needs monitoring and treatment. 相似文献
93.
Plant nuclear factor Y (NF-Y) B subunits confer drought tolerance and lead to improved corn yields on water-limited acres 总被引:12,自引:0,他引:12
Nelson DE Repetti PP Adams TR Creelman RA Wu J Warner DC Anstrom DC Bensen RJ Castiglioni PP Donnarummo MG Hinchey BS Kumimoto RW Maszle DR Canales RD Krolikowski KA Dotson SB Gutterson N Ratcliffe OJ Heard JE 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(42):16450-16455
94.
95.
Marla Francisca dos Santos Rita Nely Vilar Furtado Monique Sayuri Konai Mario Luiz Vieira Castiglioni Renata Rosa Marchetti Jamil Natour 《Clinics (S?o Paulo, Brazil)》2009,64(12):1187-1193
OBJECTIVES:
The aim of the present study was to investigate the effectiveness of Samarium153-particulate hydroxyapatite radiation synovectomy in rheumatoid arthritis patients with chronic knee synovitis.METHODS:
Fifty-eight rheumatoid arthritis patients (60 knees) with chronic knee synovitis participated in a controlled double-blinded trial. Patients were randomized to receive either an intra-articular injection with 40 mg triamcinolone hexacetonide alone (TH group) or 40 mg triamcinolone hexacetonide combined with 15 mCi Samarium153-particulate hydroxyapatite (Sm/TH group). Blinded examination at baseline (T0) and at 1 (T1), 4 (T4), 12 (T12), 32 (T32), and 48 (T48) weeks post-intervention were performed on all patients and included a visual analog scale for joint pain and swelling as well as data on morning stiffness, flexion, extension, knee circumference, Likert scale of improvement, percentage of improvement, SF-36 generic quality of life questionnaire, Stanford Health Assessment Questionnaire (HAQ), Lequesne index, use of non-steroidal anti-inflammatory drugs or oral corticosteroids, events and adverse effects, calls to the physician, and hospital visits.RESULTS:
The sample was homogeneous at baseline, and there were no withdrawals. Improvement was observed in both groups in relation to T0, but no statistically significant differences between groups were observed regarding all variables at the time points studied. The Sm/TH group exhibited more adverse effects at T1 (p<0.05), but these were mild and transitory. No severe adverse effects were reported during follow-up.CONCLUSION:
Intra-articular injection of Samarium153-particulate hydroxyapatite (15 mCi) with 40 mg of triamcinolone hexacetonide is not superior to triamcinolone hexacetonide alone for the treatment of knee synovitis in patients with rheumatoid arthritis at 1 y of follow-up. 相似文献96.
97.
98.
99.
M Duarte-Araújo C Nascimento MA Timóteo MT Magalh?es-Cardoso P Correia-de-Sá 《British journal of pharmacology》2009,156(3):519-533
Background and purpose:
The relative contribution of distinct ecto-nucleotidases to the modulation of purinergic signalling may depend on differential tissue distribution and substrate preference.Experimental approach:
Extracellular ATP catabolism (assessed by high-performance liquid chromatography) and its influence on [3H]acetylcholine ([3H]ACh) release were investigated in the myenteric plexus of rat ileum in vitro.Key results:
ATP was primarily metabolized via ecto-ATPDase (adenosine 5′-triphosphate diphosphohydrolase) into AMP, which was then dephosphorylated into adenosine by ecto-5′-nucleotidase. Alternative conversion of ATP into ADP by ecto-ATPase (adenosine 5′-triphosphatase) was more relevant at high ATP concentrations. ATP transiently increased basal [3H]ACh outflow in a 2′,3′-O-(2,4,6-trinitrophenyl)adenosine-5′-triphosphate (TNP-ATP)-dependent, tetrodotoxin-independent manner. ATP and ATPγS (adenosine 5′-[γ-thio]triphosphate), but not α,β-methyleneATP, decreased [3H]ACh release induced by electrical stimulation. ADP and ADPβS (adenosine 5′[β-thio]diphosphate) only decreased evoked [3H]ACh release. Inhibition by ADPβS was prevented by MRS 2179 (2′-deoxy-N6-methyl adenosine 3′,5′-diphosphate diammonium salt, a selective P2Y1 antagonist); blockade of ADP inhibition required co-application of MRS 2179 plus adenosine deaminase (which inactivates endogenous adenosine). Blockade of adenosine A1 receptors with 1,3-dipropyl-8-cyclopentyl xanthine enhanced ADPβS inhibition, indicating that P2Y1 stimulation is cut short by tonic adenosine A1 receptor activation. MRS 2179 facilitated evoked [3H]ACh release, an effect reversed by the ecto-ATPase inhibitor, , which delayed ATP conversion into ADP without affecting adenosine levels. ARL67156Conclusions and implications:
ATP transiently facilitated [3H]ACh release from non-stimulated nerve terminals via prejunctional P2X (probably P2X2) receptors. Hydrolysis of ATP directly into AMP by ecto-ATPDase and subsequent formation of adenosine by ecto-5′-nucleotidase reduced [3H]ACh release via inhibitory adenosine A1 receptors. Stimulation of inhibitory P2Y1 receptors by ADP generated alternatively via ecto-ATPase might be relevant in restraining ACh exocytosis when ATP saturates ecto-ATPDase activity. 相似文献100.
Mohamad G. Fakih MD MPH Margarita E. Pena MD Stephen Shemes Janice Rey MT Dorine Berriel‐Cass RN MA Susan M. Szpunar PhD Ruth T. Savoy‐Moore PhD Louis D. Saravolatz MD 《Academic emergency medicine》2010,17(3):337-340
Objectives: Avoiding placement of unnecessary urinary catheters (UCs) in the emergency department (ED) affects UC utilization during hospitalization. The authors sought to evaluate the effect of establishing institutional guidelines for appropriate UC placement coupled with emergency physician (EP) education on UC utilization. Methods: Urinary catheter utilization was measured before and after the establishment of guidelines and EP education. Data collected included the presence of a UC on ED arrival, placement of a UC in the ED, documentation of a physician order for UC placement, reasons for placement, and compliance with the guidelines. Chi‐square analyses were used to study the association between pre‐ and postintervention time periods and catheter use. Results: A total of 377 (15%) patients had UCs; only 151 (47%) UCs initially placed in the ED had a physician order documented. UC placement was appropriately indicated in 75.5% of patients with a documented physician order, but in only 52% of cases without a documented physician order (p < 0.001). The physician intervention was associated with an overall reduction in UC utilization from 16.4% to 13% (p = 0.018). Physicians ordered 40% fewer UCs postintervention compared to preintervention. Preintervention, a physician order for UC placement was found indicated in 72.6% patients, compared to 82.2% patients with UC placed postintervention (p = 0.21). Conclusions: Establishing guidelines for UC placement and physician education in the ED were associated with a marked reduction in utilization. However, addressing appropriate UC utilization may require evaluating other factors such as nursing influence on utilization. ACADEMIC EMERGENCY MEDICINE 2010; 17:337–340 © 2010 by the Society for Academic Emergency Medicine 相似文献