Background/purpose: Sunscreens are believed to be a valuable tool in providing photoprotection against the detrimental effects of UV radiation, a known carcinogen. However, a number of controversies ...have developed regarding their safety and efficacy. This review summarizes the relevant studies surrounding these controversies.
Methods: Evidence of the prevention of skin cancer, an oft‐cited reason for sunscreen use, was examined as it pertains to squamous cell carcinoma, basal cell carcinoma and melanoma. We also reviewed studies examining the effects of sunscreen on the synthesis of vitamin D, an essential nutrient whose role in health and disease continues to grow. Lastly, we analyzed studies surrounding the safety and toxicity of oxybenzone, retinyl palmitate and nanoparticles of zinc oxide (ZnO) and titanium dioxide (TiO2).
Results: The overwhelming majority of available data is drawn from studies conducted using antiquated sunscreen formulations. Nonetheless, our research revealed that topical use of sunscreen protects against squamous cell carcinoma, does not cause vitamin D deficiency/insufficiency in practice and has not been demonstrated to adversely affect the health of humans.
Conclusion: Given the established benefits of UV protection, the use of sunscreens remains an important part of an overall photoprotective strategy. Future sunscreens with improved formulation should ideally offer superior protection. With increased usage of sunscreen by the public, continuous and vigilant monitoring of the overall safety of future products is also needed.
Microscopic evaluation of the entire surgical margin during excision of cutaneous malignancies results in the highest rates of complete excision and lowest rates of true local scar recurrence. Few ...studies demonstrate the outcomes of Mohs micrographic surgery specifically for invasive melanoma of the trunk and proximal portion of the extremities.
To evaluate the long-term efficacy of Mohs micrographic surgery for invasive melanoma of the trunk and proximal portion of the extremities, including true local scar recurrence rate, distant recurrence-free survival, and disease-specific survival.
Prospectively collected study of 1416 cases of invasive melanoma of the trunk and proximal portion of the extremities was performed to evaluate long-term outcomes.
True local scar recurrences occurred in our cohort at a rate of 0.14% (2/1416), after a mean follow-up period of 75 months and were not associated with tumor depth. The rate of satellite/in-transit recurrences and the disease-specific survival stratified by tumor thickness were superior to historical control values.
We used a nonrandomized, single institution, retrospective design.
Mohs micrographic surgery of primary cutaneous invasive melanoma on the trunk and proximal portion of the extremities resulted in local control of 99.86% of tumors and an overall disease-specific death rate superior to that of wide local excision.
There have been concerns about the increased use of helium and nitrogen gas as a suicide mechanism in Australia.
National Coronial Information System data were used to investigate gas‐specific ...suicides in Australia over the period 2006–2017. Characteristics were compared between helium or nitrogen, carbon monoxide and seven other gases.
Gas inhalation accounted for 10% (3,103/31,002) of all suicide deaths in Australia between 2006 and 2017. The mean age of individuals who died by suicide was 47.6 years (SD 16.9, R 14‐97) and 83.3% were male. The number of gas suicides declined over the study period (IRR=0.96). The fall was associated with a 47% decline in carbon monoxide suicides (IRR=0.93). There was an increase in deaths due to argon (IRR=1.60) and nitrogen (IRR=1.27). Compared to individuals using other non‐carbon monoxide gases, individuals who died by suicide from helium or nitrogen were significantly more likely to be older, have a physical illness and/or disability, have contacted a euthanasia group and have accessed instructional material and purchased gas online.
Suicides by carbon monoxide decreased between 2006 and 2017 alongside an increase in argon and nitrogen gas use – particularly among older adults. The ease of access to these gases points to new targets for means restriction.
Identifying the types of gases used in suicide deaths and emerging trends may enable targeted interventions that could potentially reduce access.
Abstract Driven by new discoveries in stem-cell biology and regenerative medicine, there is broad interest in biomaterials that go beyond basic interactions with cells and tissues to actively direct ...and sustain cellular behavior. Keratin biomaterials have the potential to achieve these goals but have been inadequately described in terms of composition, structure, and cell-instructive characteristics. In this manuscript we describe and characterize a keratin-based biomaterial, demonstrate self-assembly of cross-linked hydrogels, investigate a cell-specific interaction that is dependent on the hydrogel structure and mediated by specific biomaterial–receptor interactions, and show one potential medical application that relies on receptor binding - the ability to achieve hemostasis in a lethal liver injury model. Keratin biomaterials represent a significant advance in biotechnology as they combine the compatibility of natural materials with the chemical flexibility of synthetic materials. These characteristics allow for a system that can be formulated into several varieties of cell-instructive biomaterials with potential uses in tissue engineering, regenerative medicine, drug and cell delivery, and trauma.
Chemerin connects fat to arterial contraction Watts, Stephanie W; Dorrance, Anne M; Penfold, Mark E ...
Arteriosclerosis, thrombosis, and vascular biology,
06/2013, Letnik:
33, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Obesity and hypertension are comorbid in epidemic proportion, yet their biological connection is largely a mystery. The peptide chemerin is a candidate for connecting fat deposits around the blood ...vessel (perivascular adipose tissue) to arterial contraction. We presently tested the hypothesis that chemerin is expressed in perivascular adipose tissue and is vasoactive, supporting the existence of a chemerin axis in the vasculature.
Real-time polymerase chain reaction, immunohistochemistry, and Western analyses supported the synthesis and expression of chemerin in perivascular adipose tissue, whereas the primary chemerin receptor ChemR23 was expressed both in the tunica media and endothelial layer. The ChemR23 agonist chemerin-9 caused receptor, concentration-dependent contraction in the isolated rat thoracic aorta, superior mesenteric artery, and mesenteric resistance artery, and contraction was significantly amplified (more than 100%) when nitric oxide synthase was inhibited and the endothelial cell mechanically removed or tone was placed on the arteries. The novel ChemR23 antagonist CCX832 inhibited phenylephrine-induced and prostaglandin F2α-induced contraction (+perivascular adipose tissue), suggesting that endogenous chemerin contributes to contraction. Arteries from animals with dysfunctional endothelium (obese or hypertensive) demonstrated a pronounced contraction to chemerin-9. Finally, mesenteric arteries from obese humans demonstrate amplified contraction to chemerin-9.
These data support a new role for chemerin as an endogenous vasoconstrictor that operates through a receptor typically attributed to function only in immune cells.
This study compares two North American time-activity data bases: the National Human Activity Pattern Survey (NHAPS) of 9386 interviewees in 1992-1994 in the continental USA with the Canadian Human ...Activity Pattern Survey (CHAPS) of 2381 interviewees in 1996-1997 in four major Canadian cities. Identical surveys and methodology were used to collect this data: random sample telephone selection within the identified telephone exchanges, computer-assisted telephone interviews, overselection of children and weekends in the 24-h recall diary and the same interviewers. Very similar response rates were obtained: 63% (NHAPS) and 64.5% (CHAPS). Results of comparisons by age within major activity and location groups suggest activity and location patterns are very similar (most differences being less than 1% or 14 min in a 24-h day) with the exception of seasonal differences. Canadians spend less time outdoors in winter and less time indoors in summer than their U.S. counterparts. When exposure assessments use time of year or outdoor/indoor exposure gradients, these differences may result in significant differences in exposure assessments. Otherwise, the 24-h time activity patterns of North Americans are remarkably similar and use of the combined data set for some exposure assessments may be feasible.
Previous studies on performance effects by New Zealand blackcurrant (NZBC) extract used mainly a single exercise task. We examined the effects of NZBC extract in a battery of rugby union–specific ...tests including speed, agility and strength testing. University male rugby union players (n = 13, age: 21 ± 2 years, height: 182 ± 6 cm, body mass: 87 ± 13 kg) completed two full familiarisations and two experimental visits in an indoor facility. The study had a double blind, placebo-controlled, randomised, crossover design. For the experimental visits, participants consumed NZBC extract (210 mg/day of anthocyanins for 7 days) or placebo with a 7-day wash-out. Testing order was the running-based anaerobic sprint test, the Illinois agility test, seated medicine ball (3 kg) throw, and handgrip strength. With NZBC extract, there may have been an effect for average sprint time to be faster by 1.7% (placebo: 5.947 ± 0.538 s, NZBC extract: 5.846 ± 0.571 s, d = −0.18 (trivial), p = 0.06). However, with NZBC extract there may have been reduced slowing of sprint 2 (d = −0.59 (moderate), p = 0.06) and reduced slowing for sprint 6 (d = −0.56 (moderate), p = 0.03). In the Illinois agility test, there may have also been an effect for the mean time to be faster by 1.6% (placebo: 18.46 ± 1.44 s, NZBC extract: 18.15 ± 1.22 s, d = −0.24 (small), p = 0.07). The correlation between the %change in average sprint time and %change in mean agility time was not significant (Pearson R2 = 0.0698, p = 0.383). There were no differences for the seated medicine ball throw distance (p = 0.106) and handgrip strength (p = 0.709). Intake of NZBC extract in rugby union players seems to improve tasks that require maximal speed and agility but not muscle strength. NZBC blackcurrant extract may be able to enhance exercise performance in team sports that require repeated movements with high intensity and horizontal change of body position without affecting muscle strength.
Abstract Physical activity is one of the most important determinants of cardiac function. The ability of the heart to increase delivery of oxygen and metabolic fuels relies on an array of adaptive ...responses necessary to match bodily demand while avoiding exhaustion of cardiac resources. The ATP-sensitive potassium (KATP ) channel has the unique ability to adjust cardiac membrane excitability in accordance with ATP and ADP levels, and up-regulation of its expression that occurs in response to exercise could represent a critical element of this adaption. However, the mechanism by which KATP channel expression changes result in a beneficial effect on cardiac excitability and function remains to be established. Here, we demonstrate that an exercise-induced rise in KATP channel expression enhanced the rate and magnitude of action potential shortening in response to heart rate acceleration. This adaptation in membrane excitability promoted significant reduction in cardiac energy consumption under escalating workloads. Genetic disruption of normal KATP channel pore function abolished the exercise-related changes in action potential duration adjustment and caused increased cardiac energy consumption. Thus, an expression-driven enhancement in the KATP channel-dependent membrane response to alterations in cardiac workload represents a previously unrecognized mechanism for adaptation to physical activity and a potential target for cardioprotection.
•This randomised controlled trial assessed the impact of sleep and driving education.•Intensive education improves sleep and circadian knowledge in young drivers.•Sleepiness and driving education ...enhances young drivers’ awareness of drowsiness.•Education regards sleepiness did not alter young drivers’ decisions and behaviour.•Microsleeps may be reduced in young drivers following sleepiness education.
This study assessed the impact of an education program on knowledge of sleepiness and driving behaviour in young adult drivers and their performance and behaviour during simulated night driving.
Thirty-four participants (18–26 years old) were randomized to receive either a four-week education program about sleep and driving or a control condition. A series of questionnaires were administered to assess knowledge of factors affecting sleep and driving before and after the four-week education program. Participants also completed a two hour driving simulator task at 1am after 17 h of extended wakefulness to assess the impact on driving behaviour.
There was an increase in circadian rhythm knowledge in the intervention group following the education program. Self-reported risky behaviour increased in the control group with no changes in other aspects of sleep knowledge. There were no significant differences in proportion of intervention and control participants who had microsleeps (p ≤ .096), stopped driving due to sleepiness (p = .107), recorded objective episodes of drowsiness (p = .455), and crashed (p = .761), although there was a trend towards more control participants having microsleeps and stopping driving. Those in the intervention group reported higher subjective sleepiness at the end of the drive M = 6.25, SD = 3.83, t(31) = 2.15, p = .05 and were more likely to indicate that they would stop driving M = 3.08, SD = 1.16, t(31) = 2.24, p = .04.
The education program improved some aspects of driver knowledge about sleep and safety. The results also suggested that the education program lead to an increased awareness of sleepiness. Education about sleep and driving could reduce the risk of drowsy driving and associated road trauma in young drivers, but requires evaluation in a broader sample with assessment of real world driving outcomes.
Lipophagic panniculitis of childhood is a rare condition notable clinically for an inflammatory panniculitis followed by the development of permanent lipoatrophy. In this regard, the term ...lipoatrophic panniculitis has been used synonymously with lipophagic panniculitis. Additional designations include lipophagic lipoatrophic panniculitis and annular lipoatrophic panniculitis of the ankles. Although lipophagic panniculitis has been associated with a number of autoimmune phenomena, a paucity of reports and limited pathological analyses to date renders this disease an elusive one whose pathogenesis is not yet established. We describe the clinical, histopathologic, and immunohistochemical findings in a case of lipophagic panniculitis of childhood in a 7-year-old boy and present it in the context of a comprehensive review of the literature. Furthermore, we offer a hypothesis regarding the pathogenetic basis of lipophagic panniculitis of childhood, suggesting cellular immunity targeting the adipocyte at the crux of its pathogenesis.
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