National surveillance of fungemia in Denmark (2004 to 2009).

A 6-year nationwide study of fungemia in Denmark was performed using data from an active fungemia surveillance program and from laboratory information systems in nonparticipating regions. A total of 2,820 episodes of fungemia were recorded. The incidence increased from 2004 to 2007 (7.7 to 9.6/100,000) and decreased slightly from 2008 to 2009 (8.7 to 8.6/100,000). The highest incidences were seen at the extremes of age (i.e., 11.3 and 37.1/100,000 for those <1 and 70 to 79 years old, respectively). The rate was higher for males than for females (10.1 versus 7.6/100,000, P = 0.003), with the largest difference observed for patients >50 years of age. The species distribution varied significantly by both age and gender. Candida species accounted for 98% of the pathogens, and C. albicans was predominant, although the proportion decreased (64.4% to 53.2%, P < 0.0001). C. glabrata ranked second, and the proportion increased (16.5% to 25.9%, P = 0.003). C. glabrata was more common in adults and females than in children and males, whereas C. tropicalis was more common in males (P = 0.020). C. krusei was a rare isolate (4.1%) except at one university hospital. Acquired resistance to amphotericin and echinocandins was rare. However, resistance to fluconazole (MIC of >4 µg/ml) occurred in C. albicans (7/1,183 [0.6%]), C. dubliniensis (2/65 [3.1%]), C. parapsilosis (5/83 [6.0%]), and C. tropicalis (7/104 [6.7%]). Overall, 70.8% of fungemia isolates were fully fluconazole susceptible, but the proportion decreased (79.7% to 68.9%, P = 0.02). The study confirmed an incidence rate of fungemia in Denmark three times higher than those in other Nordic countries and identified marked differences related to age and gender. Decreased susceptibility to fluconazole was frequent and increasing.

Water activity-temperature state diagram of amorphous lactose.

Development in the glass transition temperature, Tg, to reach a stabilized value for amorphous lactose stored at 5, 25, and 38 degrees C at different water activities varying from aw = 0.21 to 0.59 was followed by differential scanning calorimetry. Combinations of stabilized Tg and water activity were used for interpolation of the value of water activity, where Tg was equal to the storage temperature. These values of water activity were used to construct a state diagram in the (aw,T)-plane for lactose in the amorphous state from which critical combinations of water activity and storage temperature may be obtained for optimization of storage conditions of lactose-based dry products.

Temperature effect on lactose crystallization, maillard reactions, and lipid oxidation in whole milk powder.

Whole milk powder with an initial water content of 4.4% (w/w) and a water activity of 0.23 stored in hermetically sealed vials for up to 147 days below (37 and 45 degrees C) and above (55 degrees C) the glass transition temperature (T(g) determined to have the value 48 degrees C) showed a strong temperature dependence for quality deterioration corresponding to energies of activation close to 200 kJ/mol for most deteriorative processes. The glass transition was found not to cause any deviation from Arrhenius temperature dependence. Lactose crystallization, which occurred as a gradual process as monitored by isothermal calorimetry, is concluded to liberate bound water (a(w) increase to 0.46) with a modest time delay (approximately 2 days at 55 degrees C) and with concomitant surface browning as evidenced by an increasing Hunter b-value. Browning and formation of bound hydroxymethyl-furfural determined by HPLC seem to be coupled, while formation of another Maillard reaction product, furosine, occurred gradually and was initiated prior to crystallization. Initiation of lipid oxidation, as detected by lipid-derived radicals (high g-value ESR spectra), and progression of lipid oxidation, as detected by headspace GC, seem not to be affected by lactose crystallization and browning, and no indication of browning products acting as antioxidants could be determined.

Two types of radicals in whole milk powder. Effect of lactose crystallization, lipid oxidation, and browning reactions.

Whole milk powder was stored in closed vials at 60 degrees C to induce crystallization of lactose within a short time scale. After an induction period of 3-4 days simultaneous crystallization of lactose, increase of water activity, formation of browning products, and increase of radical content took place. Radicals detected before lactose crystallization were characterized by a narrow ESR spectrum (g = 2.006) and could be depleted by removal of oxygen and therefore were assigned to oxidation processes. Late-stage radicals present after crystallization of lactose gave much wider spectra (g = 2.0048) and were independent of oxygen availability and assigned to late-stage Maillard reaction products. The study indicates that the processes of lactose crystallization, browning, and formation of radical species (g = 2.0048) are strongly coupled, while lipid oxidation is less dependent on the other processes.