ABSTRACT
A method for rapid determination of γ-hydroxybutyric acid (GHB) in beverages (water, sodas, beer) and urine was established by direct analysis real-time mass spectrometry (DART-MS). Samples were analyzed directly after dilution with mixture of methanol and water(1:1,V/V). Instrument parameter settings were optimized to obtain the sensitive and accurate determination of GHB. At the sample introduction speed of 0.5 mm/s, high intensity of[M-H]- ions for GHB were observed in the negative ion and selection ion monitoring mode by utilization of high purity helium gas at 350℃. For different samples of water,sodas,beer and urine,the limits of detection (LODs) (S/N=3) were in the range of 1-2 μg/mL, while the limits of quantification (LOQs) (S/N=10) were in the range of 3-5 μg/mL. The linear correlation coefficients of the standard curves with different sample matrixes were between 0.9899 and 0.9980. The recoveries were in the range of 80.8%-115.2% with the relative standard deviations of 1.9%-12.8%. With its rapid analysis and simple pretreatment steps,the method is expected to have a strong advantage in the rapid screening analysis of large quantities of beverage and urine.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the impact of insulin resistance (IR) on prognosis in non-diabetic acute coronary syndrome patients.</p><p><b>METHODS</b>In this prospective study, we enrolled 332 non-diabetic patients suffering from acute coronary syndrome. The patients were divided into three groups by HOMA-IR which calculated by formula: low HOMA-IR group (HOMA-IR < 2), 44 cases; moderate HOMA-IR group (2 ≤ HOMA2-IR < 6), 99 cases; high HOMA-IR group (HOMA ≥ 6) with HOMA index, 179 cases. The in-hospital medical records of patients were compared, and all patients were followed up for one year after discharge.</p><p><b>RESULTS</b>Incidence of hypertension (P = 0.013), dyslipidemia (P < 0.001), faster resting heart rate (P < 0.001) and number of triple vessel coronary artery disease (P = 0.017) in high HOMA-IR group were significantly higher than in low and moderate HOMA-IR group. During follow-up, the major end-point events increased in proportion to IR grade: 64.3% (26/44) in the high HOMA-IR group, 54.7% (52/99) in moderate HOMA-IR group and 41.3% (74/199) in low HOMA-IR group (P = 0.034). Multivariable logistic regression analysis showed that high sensitivity C reactive protein (OR = 1.012, 95%CI:1.002-1.022, P = 0.022), HOMA-IR (OR = 1.250, 95%CI:1.043-1.497, P = 0.015) , triple vessel coronary artery disease (OR = 5.914, 95%CI:2.947-11.868, P < 0.001) , ischemic changes on ECG (OR = 5.495, 95%CI:2.925-10.324, P < 0.001) and low left ventricular ejection fraction (LVEF ≤ 40%) (OR = 13.205, 95%CI:5.000-34.661, P < 0.001) were independent risk factor for major end-point events during follow-up.</p><p><b>CONCLUSIONS</b>Increased insulin resistance is linked with poor prognosis of non-diabetic patients with acute coronary syndrome.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Acute Coronary Syndrome , Follow-Up Studies , Insulin Resistance , Logistic Models , Prognosis , Prospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To test the salivary immunoglobulin A antibody activity to Streptococcus mutans in normal with in acid environment.</p><p><b>METHODS</b>Streptococcus mutans strains were isolated from 20 volunteers, serotyped by biochemical test and PCR, and genotyped by AP-PCR. Unstimulated secretions from submandibular glands and sublingual glands were collected from volunteers by modified collectors. Each identified Streptococcus mutans genotype was cultured in two groups: control group was cultured in BHI broth pH7.2 at 37 degrees C for 2 h; acid shock group were cultured in TYEG broth (pH5.5) at 37 degrees C for 2 h. Analysis of SIgA activity to Streptococcus mutans genotypes in different groups was detected by Western blot.</p><p><b>RESULTS</b>(1) The SIgA of each individual could response to his own Streptococcus mutans strains and the reference strains; (2) The same individual had different SIgA activity to different genotype strains; (3) There were no significant difference between acid groups and control groups, in spite that some bands had strong or weak intensity.</p><p><b>CONCLUSIONS</b>Although Streptococcus mutans could express acid shock proteins in stress, the present study suggests that these new proteins have no qualitative effect on the reaction of SIgA to Streptococcus mutans.</p>