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1.

Background

Caffeine increases alertness when consumed in single servings of various products including coffee, tea, soft drinks, and energy drinks. Although not a nutrient, caffeine is consumed by 90% of the adult population in the United States.

Objective

This study examined the daily pattern of caffeine intake and its relationship to multiple demographic variables.

Methods

Data from the National Health and Nutrition Examination Survey (NHANES) 2007–2012 (adults aged 19+ years; n=16,173) were used to determine the time of day at which caffeine is consumed and demographic factors associated with intake. Regression analyses characterized factors associated with caffeine intake including sex, age, ethnicity, education, smoking status, physical activity, employment status, total work hours, alcohol, and energy intake.

Results

Mean adult per capita caffeine intake was 169±4 mg/d (mean±standard error). Most caffeine (70%) was consumed before noon, often at breakfast, and intake decreased progressively over the day, with little consumed after 9:00 pm. Intake was associated with age, ethnicity, smoking status, total calorie intake, and work hours (P<0.01) but not physical activity, economic status, education level, or employment status. Variables with the largest associations with intake were, respectively, ethnicity and age. Non-Hispanic black individuals consumed the smallest amounts (80±2 mg/d), non-Hispanic white individuals consumed the greatest amounts (194±3 mg/d), and Asian individuals (126±7 mg/d) and Hispanic individuals consumed intermediate amounts (127±3 mg/d). Middle-aged individuals (aged 50 to 54 years) consumed more caffeine (211±6 mg/d) than younger (107±4 mg/d, aged 20 to 24 years) and older individuals (153±4 mg/d, aged 75 to 79 years).

Conclusion

Most caffeine is consumed in the morning, when alertness is lowest, and very little in the evening before sleep. Ethnicity and age were the variables most strongly associated with intake; work hours, occupation, energy and alcohol intake, and smoking were also associated with intake. Because caffeine increases alertness, it is not surprising that its pattern of consumption and factors associated with its intake vary from those of most other food constituents.  相似文献   
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3.

Background

Operative management of pancreatic ductal adenocarcinoma (PDAC) is complicated by several key decisions during the procedure. Identification of metastatic disease at the outset and, when none is found, complete (R0) resection of primary tumor are key to optimizing clinical outcomes. The use of tumor-targeted molecular imaging, based on photoacoustic and fluorescence optical imaging, can provide crucial information to the surgeon. The first-in-human use of multimodality molecular imaging for intraoperative detection of pancreatic cancer is reported using cetuximab-IRDye800, a near-infrared fluorescent agent that binds to epidermal growth factor receptor.

Methods

A dose-escalation study was performed to assess safety and feasibility of targeting and identifying PDAC in a tumor-specific manner using cetuximab-IRDye800 in patients undergoing surgical resection for pancreatic cancer. Patients received a loading dose of 100 mg of unlabeled cetuximab before infusion of cetuximab-IRDye800 (50 mg or 100 mg). Multi-instrument fluorescence imaging was performed throughout the surgery in addition to fluorescence and photoacoustic imaging ex vivo.

Results

Seven patients with resectable pancreatic masses suspected to be PDAC were enrolled in this study. Fluorescence imaging successfully identified tumor with a significantly higher mean fluorescence intensity in the tumor (0.09?±?0.06) versus surrounding normal pancreatic tissue (0.02?±?0.01), and pancreatitis (0.04?±?0.01; p?<?0.001), with a sensitivity of 96.1% and specificity of 67.0%. The mean photoacoustic signal in the tumor site was 3.7-fold higher than surrounding tissue.

Conclusions

The safety and feasibilty of intraoperative, tumor-specific detection of PDAC using cetuximab-IRDye800 with multimodal molecular imaging of the primary tumor and metastases was demonstrated.
  相似文献   
4.
Donor safety is utmost important in Living donor liver transplantation (LDLT). Small for size syndrome in some recipients with left lobe donors led to the evolution of right lobe LDLT. The aim of the study was to analyze the safety of large series of right lobe (RL) donor hepatectomies and compare outcomes with left lobe (LL) and left lateral segment (LLS) donations. A consecutive cohort of 726 donors from January 2011 to January 2014 were studied; RL (n = 641, 88.3%), LL (n = 36, 4.9%) or LLS (n = 49, 6.8%) depending on the type of donation. The mean age was 34.6 ± 10 years. The overall complication rate was 22.3%. Most were Clavien grade I and II. Clavien grade IIIa, IIIb, IV and V were noted in 4.2% donors. The incidence of these major complications were comparable among RL (n = 28, 4.2%), LL (n = 1, 2.7%) and LLS (n = 2, 4.08%) (P = 0.89). Bile leak was seen in 20 donors (2.7%) and 13 were managed conservatively with prolonged or additional intra‐abdominal drainage. Seven underwent re‐exploration for bile leak. In centres experienced in right lobe LDLT, morbidity after RL donation is similar to that of LL donation; and with adequate GRWR, same 1‐year recipient outcomes.  相似文献   
5.
6.
Living donor liver transplantation (LDLT) has increased availability of liver transplantation, particularly in countries with limited access to deceased organ donors. It is unclear how individual countries address the financial impact of donation for potential living donors. Herein, living liver donor financial supports were examined, focusing on countries performing ≥10 LDLT per year in the World Health Organization Transplant Observatory. Categories included health insurance coverage, reimbursement of lost wages, employment protection, and other incentives designed to promote living liver donation. Overall, 26 countries have some form of asssistance in removing disincentives to ease the financial burden of living donation, ranging from childcare, accommodations, meals, and travel reimbursement, to coverage of medical complications post-donation. Most countries provide donation-related medical coverage. Fourteen provide reimbursement of lost wages and/or paid time off. Several unique programs were designed to incentivize living donation, including free entry to museums and observatories, parking and airline discounts, and exemptions on mortgages and medical deductibles. This study highlights the broad range of programs designed to support living liver donation in high-volume LDLT countries. The data collected in this study can provide a framework for other nations to propose and implement ethical reimbursement and incentivization for living liver donors.  相似文献   
7.

Background

Auditory neural myelination (ANM) as evaluated by auditory brainstem evoked response (ABR) during the neonatal period has been used as a surrogate outcome for long-term neurodevelopment. The validity of ANM as a surrogate outcome for long-term neurodevelopment has not been well studied.

Aim

Evaluate the association of ABR I–V interpeak latency (IPL), an index of ANM, at 35 week postmenstrual age (PMA) with language outcome at 3 years of age.

Design

Prospective study.

Subjects

24–33 week gestational age (GA) infants were eligible if they did not meet exclusion criteria: craniofacial malformation, chromosomal disorders, deafness, auditory dys-synchrony, TORCH infection, or non-English speaking parents. Infants with malignancy, head injury, encephalopathy, meningitis, blindness, or who died or relocated were also excluded.

Outcome measures

ABRs were performed at 35 week PMA using 80 dB nHL and I–V IPL (ms) measured. Auditory Comprehension (AC) and Expressive Communication (EC) were evaluated by a speech-language pathologist at 3 years of age using Preschool Language Scale.

Results

Eighty infants were studied. The mean GA and birth weight of infants were 29.2 weeks and 1336 g, respectively. There was association of worse ear I–V IPL and better ear I–V IPL with AC (Coefficient − 5.4, 95% CI: − 9.8 to − 0.9 and Coefficient − 5.5, 95% CI: − 10  to−0.9, respectively) and EC (Coefficient − 5.6, 95% CI: − 9.5  to−1.8 and Coefficient − 6.7, 95% CI: − 10.6  to−2.7, respectively) after controlling for confounders.

Conclusion

The neonatal I–V IPL is a predictor of language development at 3 years of age in preterms.  相似文献   
8.
BACKGROUND: The ability of high and low mechanical index (MI) imaging methods during myocardial contrast echocardiography (MCE) to assess the physiologic significance of coronary stenoses were compared with technetium 99m sestamibi single photon emission computed tomography (SPECT) in patients. METHODS: Intermittent ultraharmonic imaging (high MI) and power modulation angio (low MI) were performed during continuous infusions of the echo-enhancing contrast agent, Optison, at rest and after dipyridamole stress in 39 patients. Technetium 99m sestamibi SPECT was performed simultaneously. Images from the 3 apical windows were divided into 6 walls. Myocardial blood flow (MBF) velocity and MBF velocity reserve were quantified from pulsing interval versus acoustic intensity MCE curves in each wall using postprocessed images. RESULTS: Approximately 25% of the myocardial walls could not be analyzed from MCE because of artifacts. MBF velocity and MBF derived from both MCE methods increased significantly after dipyridamole in healthy patients (n = 143 and 129 walls for high and low MI, respectively), compared with those with either reversible (n = 11 and 10 walls for high and low MI, respectively) or fixed defects (n = 18 and 14 walls for high and low MI, respectively) on SPECT. Consequently, MBF velocity and MBF reserve were significantly greater for patients with normal perfusion. Receiver operator characteristic curves obtained for MBF velocity reserve provided a sensitivity and specificity of 82% and 87%, respectively, for high MI; versus 64% and 96%, respectively, for low MI imaging after uninterpretable images were excluded from analysis. CONCLUSIONS: Both high and low MI MCE imaging techniques can be used to determine the presence of perfusion defects as identified by technetium 99m sestamibi SPECT. Low MI imaging methods have a number of drawbacks that limit its sensitivity compared with high MI techniques.  相似文献   
9.
10.
Dural arteriovenous fistulas (DAVFs) are fistulas connecting the branches of dural arteries to dural veins or a venous sinus. Osteodural fistulas are a rare subset of this group of diseases. We wish to report a rare case of an osteodural arteriovenous fistula at the foot of the superior ophthalmic vein (SOV), treatment of which required an unusual surgical approach via the orbit and SOV. Though access for endovascular treatment via the SOV for treatment of caroticocavernous fistulas is reported, the external approach is relatively infrequently performed, outside Europe and the Americas, with this being the first reported procedure from the Indian subcontinent. We wish to explain the steps of this unusual surgical access and highlight the salient precautions and pitfalls in the technique.  相似文献   
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