Fatty acid composition of the fat in selected food items with emphasis on trans components1

The fat in 220 samples from 35 food types has been analyzed for component fatty acids by gas liquid chromatography on a 15-m capillary column coated with SP-2340. The methodology permitted the determination of trans-octadecenoic fatty acids in the food samples. For food types in which the majority of samples containedtrans fatty acids, the range (weight percent of methyl esters) of this class of acids arranged by fat content of the food types was: high fat levels (>70% fat) — animal and dairy fats, 0.3–6.6%, stick margarines, 15.9–31.0%, tub margarines, 6.8–17.6%, and vegetable shortenings, 8.7–35.4%; moderately high fat levels (40–70% fat) —diet margarines, 11.3–13.3%; moderate fat levels (10–40% fat) — breading mixes and fried crusts, 8.1–32.7%, cakes, candies and frostings, 3.2–33.2%, cream substitutes, 0.4–11.5%, cookies, 2.5–34.2%, crackers, 1.9–29.0%, pastries and pastry crusts, 0.6–31.2%, corn and mixed grain snack chips, 0.4–30.4%; low fat levels (<10% fat) - breads and rolls, 0.2–23.6%, pretzels, 10.8–29.2%, and puddings, 28.4-35.1%. The majority of samples in the following food types did not containtrans fatty acids, except in cases where the label indicated partial hydrogenation of the oil: mayonnaises and salad dressings, salad and cooking oils and potato chips. For samples in these three food types which containedtrans fatty acids, the range was 0.2-23.2%. None of the peanut butters or pizza crusts analyzed containedtrans fatty acids.     

铅锌尾矿重金属释放影响因素的探讨

铅锌尾矿废渣若不经过处理,会通过风蚀、径流对环境造成重金属污染,对尾矿废渣污染的研究一直是大家关注的方向。多年来,pH被证实是影响重金属释放的重要因素。本文通过实验,研究了浸提方法、pH和盐度对铅锌尾矿废渣重金属元素释放的影响。结果表明,Pb、Zn、Cd、As在pH值呈酸性和碱性时浸出率都较高,Cu、Ni则在pH值为碱性时浸出率更高,盐度对Pb的释放影响效果更为明显。     

应用己酸菌及人工培养窖泥提高浓香型青稞酒质量的研究

详细叙述了己酸菌及窖泥的培养方法,以及应用己酸菌及人工培养窖泥提高浓香型青稞酒质量的研究全过程     

谷糠多酚对酒精性胃黏膜损伤的保护作用

目的：初步阐明谷糠多酚对酒精性胃黏膜损伤的保护作用以及具体分子机制,为谷糠多酚在饮酒人群胃黏膜损伤营养干预方面的应用提供科学依据。方法：雄性Wistar大鼠连续3 周每天灌胃50 mg/kg mb谷糠多酚,干预结束后通过灌胃体积分数75%乙醇溶液建立急性酒精性胃黏膜损伤模型;利用不同剂量（1～15 μg/mL）谷糠多酚对人胃黏膜上皮细胞（GES-1）处理24 h,继而通过1 000 mmol/L酒精继续作用12 h建立酒精性GES-1细胞损伤及干预模型;通过解剖观察大鼠胃组织形态学及病理结构,评价谷糠多酚对大鼠胃黏膜组织的保护作用;结合细胞形态变化及存活情况评价谷糠多酚对GES-1细胞的保护作用;通过测定氧化应激和细胞凋亡相关指标,评价谷糠多酚对急性酒精性胃黏膜损伤大鼠及GES-1细胞的抗氧化和抑制凋亡能力的影响。结果：谷糠多酚可以有效预防酒精引起的大鼠胃黏膜及GES-1细胞损伤,极显著缓解酒精引起的GES-1细胞活性氧（reactive oxygen species,ROS）水平升高（P＜0.01）;同时极显著缓解大鼠胃黏膜组织和GES-1细胞中丙二醛（methane dicarboxylic aldehyde,MDA）水平升高（P＜0.01）,提高超氧化物歧化酶（superoxide dismutase,SOD）活力,明显抑制酒精引起的细胞凋亡。结论：谷糠多酚能够通过缓解酒精引起的胃黏膜上皮细胞氧化损伤从而保护胃黏膜。     

Assessment of risk for severe hypoglycemia among adults with IDDM: validation of the low blood glucose index

OBJECTIVE: To evaluate the clinical/research utility of the low blood glucose index (LBGI), a measure of the risk of severe hypoglycemia (SH), based on self-monitoring of blood glucose (SMBG). RESEARCH DESIGN AND METHODS: There were 96 adults with IDDM (mean age 35+/-8 years, duration of diabetes 16+/-10 years, HbA1 8.6+/-1.8%), 43 of whom had a recent history of SH (53 did not), who used memory meters for 135+/-53 SMBG readings over a month, and then for the next 6 months recorded occurrence of SH. The SMBG data were mathematically transformed, and an LBGI was computed for each patient. RESULTS: The two patient groups did not differ with respect to HbA1, insulin units per day, average blood glucose (BG) and BG variability. Patients with history of SH demonstrated a higher LBGI (P < 0.0005) and a trend to be older with longer diabetes duration. Analysis of odds for future SH classified patients into low- (LBGI <2.5), moderate- (LBGI 2.5-5), and high- (LBGI >5) risk groups. Over the following 6 months low-, moderate-, and high-risk patients reported 0.4, 2.3, and 5.2 SH episodes, respectively (P = 0.001). The frequency of future SH was predicted by the LBGI and history of SH (R2 = 40%), while HbA1, age, duration of diabetes, and BG variability were not significant predictors. CONCLUSIONS: LBGI provides an accurate assessment of risk of SH. In the traditional relationship history of SH-to-future SH, LBGI may be the missing link that reflects present risk. Because it is based on SMBG records automatically stored by many reflectance meters, the LBGI is an effective and clinically useful on-line indicator for SH risk.     

Circadian variations in the occurrence of cardiac arrests: initial and repeat episodes

The purpose of this study was to predict diameters of lesions induced by laser-induced thermotherapy (LITT) of benign prostatic hyperplasia (BPH) from MRI signal/tissue temperature correlations during on-line monitoring with a temperature-sensitive fast low-angle shot (FLASH) sequence. Twenty LITT procedures with Nd:YAG (1,064 nm) and diode (830 nm) lasers were monitored on line with a T1-weighted FLASH sequence at 1.5 Tesla. Interstitial prostate temperature (T) was measured on line in 10 LITT procedures and laser energy deposition in 12. Slopes of linear regression curves for signal intensity (SI) over T were applied to determine SI at 60 degrees C to estimate diameters of intraprostatic LITT lesions. Diameters of unperfused LITT lesion cores in contrast-enhanced T1-weighted images served as gold standards. Linear regression curves with an average slope of -.54% SI/degrees C were obtained in 17 LITT procedures. Correlation coefficients were r = .92-.95 for SI/T and SI/energy deposition. Baseline variation of SI at body temperature was +/-3.9%, corresponding to +/-7 degrees C. Prediction of size (13 lesions) from on-line FLASH imaging was correct in 10 of 13, whereas 3 lesions were overestimated. Prediction of LITT lesion diameters from on-line MRI monitoring is possible with a temperature-sensitive FLASH sequence in the prostate. Accuracy may suffice to assign target regions of interest to tissue locations to be protected from coagulation.     

Effect of radiographic positioning on interpretation of cubital joint congruity in dogs

OBJECTIVE: To ascertain effects of x-ray beam centering and limb position on apparent congruity of a normal cubital joint (elbow). ANIMALS: 6 skeletally mature male Treeing Walker Coonhounds without physical, radiographic, or gross evidence of elbow abnormalities. PROCEDURE: Relative movement among humerus, radius, and ulna and measured joint space width on mediolateral and craniocaudal radiographic views was compared, using various x-ray beam centering and limb positions. RESULTS: Highest agreement and greatest certainty on subjective determination of congruity was for the flexed 90 degrees mediolateral radiographic view with the x-ray beam centered on the elbow. Distortion artifact of the proximal ulnar measurements was significant when the x-ray beam was centered on the midpoint of the radius. On the mediolateral view, the humeroradial joint space became significantly wide when the elbow was flexed. On the craniocaudal view, maximal humeroradial joint space width was obtained when the x-ray beam bisected the angle of the joint or was angled +30 degrees toward the humerus. CONCLUSIONS: Artifact distortion of joint width affected objective and subjective assessment of elbow congruity when the limb was placed in extreme flexion or extension or when the x-ray beam was not centered over the area of interest. Optimal visualization of the humeroradial joint space on the craniocaudal view was achieved when the x-ray beam bisected the angle of the elbow or was slightly angled toward the humerus. CLINICAL RELEVANCE: Elbow congruity was best assessed on the flexed 90 degrees lateral radiographic view with the x-ray beam centered on the joint.     

Constitutive expression of terminal deoxynucleotidyl transferase in transgenic mice is sufficient for N region diversity to occur at any Ig locus throughout B cell differentiation

N region diversity in Ag receptors is a developmentally regulated process in B and T cells that correlates with the differential expression of terminal deoxynucleotidyl transferase (TdT). Absent in fetal and newborn mice, TdT expression is restricted to early T and pro-B cells in adults. To extend the TdT expression pattern throughout B cell ontogenesis, we generated transgenic mice carrying a TdT cDNA under the regulatory elements of the N-myc gene and the IgH enhancer. High expression was observed in secondary lymphoid organs consistent with TdT activity beyond the pre-B cell stage. This suggests that TdT transgene expression is not down-regulated as is the endogenous gene. Unlike normal mice, extensive N region diversity was found in rearranged lambda light chain genes of adult transgenic animals. Therefore, expression of TdT appears sufficient for N region diversity to occur at any Ig locus. More importantly, expression of the transgene takes place during fetal development. As a consequence, the potential fetal B cell repertoire is modified as both rearranged heavy and light chain genes now show N region additions. Constitutive expression of TdT throughout B cell differentiation does not therefore appear deleterious and suggests that TdT is recruited only to participate in the V(D)J recombination process.