Sleep, sleepiness, and behavior problems in children with headache

The purpose of this study was to assess sleep, daytime sleepiness, and behavior problems in children suffering from headaches and in controls, with a special focus on the role of gender. A clinical group of 28 children with persistent headache complaints and a control group of 108 healthy children were included. Sleep was assessed by actigraphy and diaries. Behavior problems were assessed by parental reports. In comparison with the control group, the sleep quality of the clinical group was poorer and they complained more about excessive daytime sleepiness. Children suffering from headache showed higher levels of internalizing behavior problems. Gender was found to be a moderating factor for the relationships between headache and sleep. Compared with control girls, girls suffering from headaches had poorer sleep quality, whereas the opposite was true for the boys. The results highlight the importance of assessing sleep, daytime sleepiness, and psychologic adjustment in children complaining about headaches as an integral part of their routine assessment.     

Optical-thermal mathematical model for endovenous laser ablation of varicose veins

Endovenous laser ablation (EVLA) is successfully used to treat varicose veins. However, the exact working mechanism is still not fully identified and the clinical procedure is not yet standardized. Mathematical modeling of EVLA could strongly improve our understanding of the influence of the various EVLA processes. The aim of this study is to combine Mordon's optical-thermal model with the presence of a strongly absorbing carbonized blood layer on the fiber tip. The model anatomy includes a cylindrically symmetric blood vessel surrounded by an infinite homogenous perivenous tissue. The optical fiber is located in the center of the vessel and is withdrawn with a pullback velocity. The fiber tip includes a small layer of strongly absorbing material, representing the layer of carbonized blood, which absorbs 45 % of the emitted laser power. Heat transfer due to boiling bubbles is taken into account by increasing the heat conduction coefficient by a factor of 200 for temperatures above 95 °C. The temperature distribution in the blood, vessel wall, and surrounding medium is calculated from a numerical solution of the bioheat equation. The simulations were performed in MATLAB? and validated with the aid of an analytical solution. The simulations showed, first, that laser wavelength did virtually not influence the simulated temperature profiles in blood and vessel wall, and, second, that temperatures of the carbonized blood layer varied slightly, from 952 to 1,104 °C. Our improved mathematical optical-thermal EVLA model confirmed previous predictions and experimental outcomes that laser wavelength is not an important EVLA parameter and that the fiber tip reaches exceedingly high temperatures.     

How we started performing endovenous thermal ablation procedures: a personal history

This story is a personal journey of two Dutch dermatologists pioneering in the field of endovenous laser ablation of varicose veins, illustrating how innovations find their way in medicine and, in particular, in surgical specialties. After the introduction of these thermal ablative procedures in 2001, we have fully embraced these minimally invasive techniques, and in the process, we have increased our understanding on its mechanism of action and confirmed the clinical relevance of treating varicose veins with endovenous laser ablation. In 2013, thermal ablation is considered a standard of care by physicians as well as patients with varicose veins.     

Postremission therapy with two different dose regimens of cytarabine in adults with acute myelogenous leukemia

Sixty-seven out of 105 (64%) adults with de novo acute myelogenous leukemia (AML), achieving complete remission after induction chemotherapy, entered two successive postremission treatment protocols. Between 1987 and 1989, 35 patients received an intermediate dose of cytarabine (IDAC) along with other drugs. Between 1990 and 1993, 32 patients received high dose cytarabine (HIDAC) with similar other drugs. Patients treated with IDAC had a median survival of 13.8 months (95% Cl 11.2–23.1 months) and a 2 year survival of 34.3 ± 8.0%. Patients receiving HIDAC had a median survival of 35.5 months (95% Cl, lower limit 29.8 months) and a 2 year survival of 71.6 ± 9.4% (P < 0.002). The 2 year actuarial leukemia-free survival (LFS) was 17.8 ± 6.6% in the IDAC group and 67.3 ± 10.0% months in the HIDAC group (P = 0.004). The HIDAC group had a significant 2 year survival advantage over the IDAC group only in patients younger than 45 years. The 2 year survival in the first group was 83.3 ± 10.8% versus 23.5 ± 10.3% in the IDAC group (P = 0.0001). In patients older than 45 years, no significant differences in 2 year survival was noticed (52.9 ± 15.78 versus 44.4 ± 11.7, P = 0.8). Censoring the 21 patients who underwent bone marrow transplantation (BMT) at BMT did not change significantly the survival analysis of the patients in each group. This study is consistent with previous reports favoring HIDAC intensification in the postremission treatment of young patients with AML.     

Peripheral nerve ischemia: apolipoprotein E deficiency results in impaired functional recovery and reduction of associated intraneural angiogenic response

Apolipoprotein E-knockout (apoE KO) mice have peripheral sensory nerve defects, reduced and delayed response to noxious thermal stimuli, abnormal morphology of unmyelinated fibers, and impaired blood-nerve and blood-brain barriers. In this study, we show that, compared to wild-type mice, peripheral nerves of apoE KO mice have impaired ability to respond to ischemia, as demonstrated by measurement of motor and sensory conduction velocity. In addition, mice lacking apoE exhibit a deficit of reinnervation of ischemic epidermis, evaluated by immunofluorescent staining for the pan-neuronal marker PGP 9.5. Also regional nerve blood flow, measured by laser Doppler, and intraneural angiogenesis after ischemia are significantly compromised in apoE-deficient mice. Finally, upregulation of the angiogenic cytokine vascular endothelial growth factor (VEGF), which physiologically occurs after ischemia in the peripheral nerve of wild-type mice, is severely impaired in apoE KO mice. Among the several neural defects that have already been described in mice lacking apoE, this is the first demonstration that functional recovery to ischemia is impaired in the peripheral nerves of these animals. This deficit is mirrored by the inability of upregulating VEGF and mounting an appropriate intraneural angiogenic response following injury. These findings provide new evidence of possible interdependent relationships between VEGF, angiogenesis, and nerve function and regeneration and may provide new important information on the role of apoE in the nervous system.     

Evolution of genomic diversity and sex at extreme environments: fungal life under hypersaline Dead Sea stress

We have found that genomic diversity is generally positively correlated with abiotic and biotic stress levels (1-3). However, beyond a high-threshold level of stress, the diversity declines to a few adapted genotypes. The Dead Sea is the harshest planetary hypersaline environment (340 g.liter-1 total dissolved salts, approximately 10 times sea water). Hence, the Dead Sea is an excellent natural laboratory for testing the "rise and fall" pattern of genetic diversity with stress proposed in this article. Here, we examined genomic diversity of the ascomycete fungus Aspergillus versicolor from saline, nonsaline, and hypersaline Dead Sea environments. We screened the coding and noncoding genomes of A. versicolor isolates by using >600 AFLP (amplified fragment length polymorphism) markers (equal to loci). Genomic diversity was positively correlated with stress, culminating in the Dead Sea surface but dropped drastically in 50- to 280-m-deep seawater. The genomic diversity pattern paralleled the pattern of sexual reproduction of fungal species across the same southward gradient of increasing stress in Israel. This parallel may suggest that diversity and sex are intertwined intimately according to the rise and fall pattern and adaptively selected by natural selection in fungal genome evolution. Future large-scale verification in micromycetes will define further the trajectories of diversity and sex in the rise and fall pattern.     

The increased risk of skin cancer is persistent after discontinuation of psoralen+ultraviolet A: a cohort study

Psoralen+ultraviolet A-treated psoriasis patients are at increased risk for nonmelanoma skin cancer. To assess the persistence of cancer risk among patients who have discontinued psoralen+ultraviolet A and the risk of a first tumor with the passage of time, we prospectively studied the incidence in a cohort of 1,380 psoriasis patients treated with psoralen+ultraviolet A. We observed a total of 27,840 person-years of which 59.4% were considered years without psoralen+ultraviolet. No significant decrease in risk was noted during the first 15 years after psoralen+ultraviolet A was discontinued. Subsequently, the risk of squamous cell carcinoma was reduced (incidence rate ratio=0.79; 95%CI=0.62, 1.01 on treatment vs >15 years off). After 25 years, about 7% of patients with < or =200 psoralen+ultraviolet A treatments and more than half of the patients with > or =400 treatments develop at least one squamous cell carcinoma. After 25 years, almost one third of the patients exposed to > or =200 treatments developed at least one basal cell carcinoma. In conclusion, substantial exposure to psoralen+ultraviolet A dramatically increases the risk of nonmelanoma skin cancer and prior exposure to psoralen+ultraviolet A remains an important issue in the management of patients because the cancer risk associated with psoralen+ultraviolet A is persistent.