A prospective study of coffee intake and pancreatic cancer: results from the NIH-AARP Diet and Health Study

Background:

Evidence evaluating the association between type of coffee intake (caffeinated, decaffeinated) and risk of pancreatic cancer is limited.

Methods:

In the US NIH-AARP Diet and Health Study, we used Cox proportional hazards regression to estimate hazard ratios and 95% confidence intervals (CIs) for coffee intake and risk of pancreatic cancer among 457 366 US adults.

Results:

Over 4 155 256 person-years of follow-up, 1541 incident first primary pancreatic cancers occurred. Following detailed adjustment for tobacco smoking history, risk estimates for coffee drinking were not statistically significant; compared with never drinkers of coffee, the hazard ratios (95% CI) were 1.05 (0.85–1.30), 1.06 (0.86–1.31), 1.03 (0.85–1.25), 1.00 (0.79–1.25), and 1.24 (0.93–1.65) for <1, 1, 2–3, 4–5, and ≥6 cups per day, respectively (P-value for trend 0.46). The observed null association was consistent across all examined strata (sex, smoking status, coffee caffeination, and prevalent diabetes).

Conclusions:

In a prospective study of coffee intake with the largest number of pancreatic cancer cases to date, we did not observe an association between total, caffeinated, or decaffeinated coffee intake and pancreatic cancer.     

咖啡摄入前后心率变异性的对比研究

目的研究中等剂量咖啡摄入对青年受试者心率变异性的影响,明确咖啡对心脏自主神经活性的作用。方法无咖啡因摄入习惯的16名健康青年受试者(身高167 cm±7.2 cm、体重61.3 kg±6.3kg、年龄24.9岁±2.8岁)参与本项研究,在摄入含6 mg/kg咖啡因的咖啡饮品后,于8:40~10:45应用动态心电图记录仪(Holter)进行咖啡摄入前后心电信号的采集及心率(heart rate,HR)和心率变异性指标的分析。心率变异性指标包括R-R间期标准差(SDNN)、相邻R-R间期差值的均方根值(r MSSD)、相邻的R-R间期之差大于50 ms的心搏数占总心搏数的百分比(PNN50)、标化低频(normalized low frequency power,LFnorm)、标化高频(normalized high frequency power,HFnorm)、低频功率(low frequency,LF)与高频功率(high frequency,HF)的比值(LF/HF)。结果饮用咖啡后,心率、心率变异性指标均发生改变且具有统计学意义,HR、LFnorm和LF/HF分别降低了7.5%、17%和35%。r MSSD、PNN50和HFnorm分别提高了82%、80%和58%。其中HR及LF/HF随着时间的变化趋势最明显。HRV参数在饮用咖啡前后的差值ΔLF与ΔHF,ΔLF与ΔLF/HF均显著相关,相关系数为-0.980和0.903。结论中等剂量咖啡可引起心率变异性的改变和心率的降低,抑制交感神经活性,提高副交感神经活性。     

Melatonin and serotonin profiles in beans of Coffea species

A high-performance liquid chromatography (HPLC) and an electrospray ionization mass spectrometry (LC/ESI-MS) methods were applied to quantify the profiles of melatonin and serotonin (5-HT) in green and roasted beans of Coffea canephora (robusta) and Coffea arabica (arabica). Both melatonin and 5-HT were detected in green coffee beans (5.8±0.8μg/g dry weight (DW), 10.5±0.6μg/g DW) and also in roasted beans of C. canephora (8.0±0.9μg/g DW, 7.3±0.5μg/g DW). Melatonin (3.0±0.6μg/50mL) and 5-HT (4.0±0.7μg/50mL) were detected in coffee brew. In C. arabica, 5-HT was high in green beans (12.5±0.8μg/g DW) compared with roasted beans (8.7±0.4). The levels of melatonin were higher (9.6±0.8μg/g DW) in roasted beans compared with green beans (6.8±0.4μg/g DW). Both melatonin (3.9±0.2μg/50mL) and 5-HT (7.3±0.6μg/50mL) were detected in coffee brew. Because of the relevance of indoleamines as bioactive molecules with implications for food, nutritional sciences and human health, it was of interest to explore their levels in coffee, an important universal beverage.     

The effect of at-home bleaching and toothbrushing on removal of coffee and cigarette smoke stains and color stability of enamel

BackgroundThe authors conducted a study to evaluate the stain removal ability of tooth bleaching and simulated toothbrushing after coffee and cigarette smoke staining and to determine the enamel susceptibility to restaining.MethodsThe authors used a colorimeter to determine the baseline color of 40 bovine labial enamel surfaces according to the Commission Internationale de l'Eclairage L*a*b* coordinates. They immersed one-half of the specimens in coffee and exposed one-half to cigarette smoke in a smoking machine. They took color measurements again and determined the color change from baseline (ΔE1) for each group. The authors divided each group into two subgroups and subjected the specimens to at-home bleaching (one hour per day for 21 days) or simulated toothbrushing (120 cycles per day for 21 days), followed by another color measurement (ΔE2). The authors repeated both staining procedures (that is, cigarette smoke and coffee) and followed them with a third color measurement (ΔE3). They analyzed the data by using a two-way analysis of variance and the Tukey test (α = 5 percent).ResultsBoth staining procedures resulted in similar values for ΔE1. The specimens stained with coffee and cigarette smoke exhibited a significant reduction in color change after bleaching (P < .05). However, toothbrushing resulted in a significantly reduced color change only for cigarette smoke–stained specimens (P < .001). The discoloration in coffee-stained specimens increased after restaining, irrespective of the stain removal method (P < .05).ConclusionsThe study results show that at-home bleaching removed both coffee and cigarette smoke staining. The restaining potential was greater for specimens stained with coffee than for those stained with cigarette smoke, regardless of the removal method used.Clinical ImplicationsSix percent hydrogen peroxide at-home bleaching was effective in removing stains caused by coffee or cigarette smoke. However, continued frequent consumption of coffee can increase the staining susceptibility of enamel.     

Environmental factors and chronic unexplained dyspepsia

A subgroup of patients with nonulcer dyspepsia (NUD) have no definite cause for their dyspepsia, termed essential dyspepsia.The aim of the present study was to determine if environmental factors are associated with essential dyspepsia. The patterns of ingestion of analgesic drugs (aspirin, acetaminophen, dextropropoxyphene), nonaspirin, nonsteroidal antiinflammatory drugs, alcohol, coffee, tea, and smoking in 113 essential dyspepsia patients were compared with 113 randomly selected community controls matched for age, sex, and social grade. Associations were studied in two six-month periods, before diagnosis in all patients and before the onset of NUD in those patients with a short history of dyspepsia. It was found that acetaminophen ingestion was associated with essential dyspepsia, and this association was present both before the onset of the dyspepsia (OR 3.1, 95% CI 1.3– 7.1) and before diagnosis (OR 1.8, 95% CI 1.2– 2.6). None of the other environmental factors were associated with essential dyspepsia.     

Exploring in vitro neurobiological effects and high-pressure liquid chromatography-assisted quantitation of chlorogenic acid in 18 Turkish coffee brands

The hydroalcoholic extracts of the Turkish traditional coffee samples from 18 commercial brands were tested for their neurobiological effects through enzyme inhibition based on enzyme-linked immunosorbance microtiter assays against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, linked to Alzheimer’s and Parkinson’s diseases. The extracts were also subjected to several antioxidant test systems to define their antiradical, metal-chelation capacity, and reducing power. Total phenol and flavonoid contents in the extracts were delineated by spectrophotometric methods, while chlorogenic acid in the coffee samples was quantified by high-pressure liquid chromatography. The extracts displayed low to moderate inhibition (from 2.13 ± 0.01% to 36.12 ± 1.07% at 200 μg/mL) against the tested enzymes, whereas they had notable 2,2′-diphenyl-1-picrylhydrazyl radical scavenging activity up to 56.15 ± 2.03% at 200 μg/mL. The extracts exerted a remarkable ferric-reducing antioxidant power values, while chlorogenic acid was found to range between 0.288 ± 0.005% and 2.335 ± 0.010%.     

Meta分析中剂量反应关系的分析方法及其应用

 目的  介绍Meta分析中的剂量反应关系分析方法的应用。方法  首先介绍了Meta分析中的剂量反应关系分析方法,再通过利用咖啡与前列腺癌发病风险关系的研究文献为例,具体说明剂量反应关系分析方法。结果  利用实例说明广义最小二乘估计法和限制三次样条法在Meta分析剂量反应关系中的应用,数据分析由Stata软件中的 “GLST”、 “MKSPLINE”等命令来完成。共检索到12项关于饮咖啡与前列腺癌发病风险的队列研究文献,包括39 943名病例数和577 458名对象;12项病例对照研究文献,包含7 909名病例和9 461名对照。分析结果表明,每天多饮一杯咖啡,罹患前列腺癌风险降低为原来的0.992 (95% CI:0.986~0.999),有临界统计学意义。结论    当暴露为连续变量时,Meta分析中提供剂量反应关系的结果能够更好地呈现暴露因素不同剂量水平与结局之间的关系,使结果更丰富,值得在肿瘤或慢性病流行病学研究中推广应用。     

热毒宁注射液化学成分、药理作用及临床应用研究进展

热毒宁注射液具有清热、疏风、解毒的功效,临床上主要用于治疗外感风热所致的感冒、咳嗽及上呼吸道感染、急性支气管炎等,其临床疗效确切,安全性好,应用广泛。热毒宁注射液的化学成分主要包括环烯醚萜类、木脂素类、香豆素类、倍半萜类、黄酮类、咖啡酰奎宁酸类、酚酸类等。通过查阅近几年与热毒宁注射液相关的国内外文献,对其化学成分、药理作用及临床应用进行综述。     

Recovery of phenolic compounds from spent coffee grounds through optimized extraction processes

The aim of the present study was to compare novel methods and technologies of phenolics extraction from spent coffee grounds, as “green” alternative techniques of the conventional ethanol extraction. Three extraction techniques, ultrasound- and microwave-assisted extraction, along with the use of β-cyclodextrin as a solvent have been studied and optimized as the eco-friendly solutions for the efficient extraction of phenolic compounds from Spent Coffee Grounds (SCG). The investigated factors were temperature (20–60 °C), solvent concentration (0–100% v/v water ethanol, EtOH), amplitude (20–60%), and liquid/solid ratio (5–60 mL/g) for ultrasound-assisted extraction (UAE). In the case of microwave extraction (MAE), the effects of solvent concentration (0–100% v/v), liquid/solid ratio (5–60 mL/g), and power (100–600 Watt) were studied. Ethanol (0–100% v/v) and β-cyclodextrin (β-CD, 1–18.5 mg/mL) were also compared as solvents, under the same range of liquid/solid ratio (5–60 mL/g) and temperatures (20–60 °C). In addition, the effect of the drying method (oven drying and freeze-drying), as well as a defatting pretreatment of SCG, were studied under the optimum conditions of each extraction method. The optimum extraction yield (31.79 ± 0.25 mg GAE/g SCG) was achieved using MAE with a liquid/solid ratio of 60 mL/g, a power level 600 W, and a solvent concentration of 68% v/v EtOH. While the maximum yield (34.43 mg GAE/g SCG) was also obtained by the same method from the freeze-dried sample.