Sleep, napping and alertness during an overwintering mission at Belgrano II Argentine Antarctic station.

During Antarctic isolation personnel are exposed to extreme photoperiods. A frequent observation is a sleep onset phase delay during winter. It is not known if, as a result, daytime sleeping in the form of naps increases. We sought to assess sleep patterns - with focus on daytime sleeping - and alertness in a Latin American crew overwintering in Argentine Antarctic station Belgrano II. Measurements were collected in 13 males during March, May, July, September and November, and included actigraphy and psychomotor vigilance tasks. Sleep duration significantly decreased during winter. A total of eight participants took at least one weekly nap across all measurement points. During winter, the nap onset was delayed, its duration increased and its efficiency improved. We observed a significant effect of seasonality in the association of evening alertness with sleep onset. Our results replicate previous findings regarding sleep during overwintering in Antarctica, adding the description of the role of napping and the report of a possible modulatory effect of seasonality in the relation between sleep and alertness. Napping should be considered as an important factor in the scheduling of activities of multicultural crews that participate in Antarctica.

Antiproliferative activities of lesser galangal (Alpinia officinarum Hance Jam1), turmeric (Curcuma longa L.), and ginger (Zingiber officinale Rosc.) against acute monocytic leukemia.

Acute monocytic leukemia (AML M5 or AMoL) is one of the several types of leukemia that are still awaiting cures. The use of chemotherapy for cancer management can be harmful to normal cells in the vicinity of the target leukemia cells. This study assessed the potency of the extracts from lesser galangal, turmeric, and ginger against AML M5 to use the suitable fractions in neutraceuticals. Aqueous and organic solvent extracts from the leaves and rhizomes of lesser galangal and turmeric, and from the rhizomes only of ginger were examined for their antiproliferative activities against THP-1 AMoL cells in vitro. Lesser galangal leaf extracts in organic solvents of methanol, chloroform, and dichloromethane maintained distinctive antiproliferative activities over a 48-h period. The turmeric leaf and rhizome extracts and ginger rhizome extracts in methanol also showed distinctive anticancer activities. The lesser galangal leaf methanol extract was subsequently separated into 13, and then 18 fractions using reversed-phase high-performance liquid chromatography. Fractions 9 and 16, respectively, showed the greatest antiproliferative activities. These results indicate that the use of plant extracts might be a safer approach to finding a lasting cure for AMoL. Further investigations will be required to establish the discriminatory tolerance of normal cells to these extracts, and to identify the compounds in these extracts that possess the antiproliferative activities.

Association of Crohn's disease, thiopurines, and primary epstein-barr virus infection with hemophagocytic lymphohistiocytosis.

OBJECTIVE: To assess the incidence of hemophagocytic lymphohistiocytosis (HLH) in a well-defined population of children with inflammatory bowel disease (IBD) and evaluate the common clinical and laboratory characteristics of individuals with IBD who developed HLH. STUDY DESIGN: We conducted a retrospective study of all children who developed HLH over an 8-year period. The incidence of HLH in patients with IBD was calculated using US census data and a statewide project examining the epidemiology of pediatric IBD. RESULTS: Among children in Wisconsin, 20 cases of HLH occurred during the study period; 5 cases occurred in children with IBD. Common characteristics include: Crohn's disease (CD), thiopurine administration, fever lasting more than 5 days, lymphadenopathy, splenomegaly, anemia, lymphopenia, and elevated serum triglycerides and ferritin. Of the patients, 4 had primary Epstein-Barr virus infections. The incidence of HLH among all children in Wisconsin was 1.5 per 100 000 per year. The risk was more than 100-fold greater for children with CD (P < .00001). CONCLUSIONS: Pediatric patients with CD are at increased risk for developing HLH; primary Epstein-Barr virus infection and thiopurine administration may be risk factors.