A glossary for biometeorology

Here we present, for the first time, a glossary of biometeorological terms. The glossary aims to address the need for a reliable source of biometeorological definitions, thereby facilitating communication and mutual understanding in this rapidly expanding field. A total of 171 terms are defined, with reference to 234 citations. It is anticipated that the glossary will be revisited in coming years, updating terms and adding new terms, as appropriate. The glossary is intended to provide a useful resource to the biometeorology community, and to this end, readers are encouraged to contact the lead author to suggest additional terms for inclusion in later versions of the glossary as a result of new and emerging developments in the field.     

Aquaporins and biological rhythm

Aquaporins are membrane-intrinsic proteins that facilitate membrane transport of water and small solutes or even gases. Aquaporin genes are found in almost all living organisms. In plants the proteins account for water uptake and transport as well as CO₂ availability for photosynthesis. These processes are subjected to diurnal or circadian regimes. Expression and even function of aquaporins also follows day - night rhythms. Significance of aquaporin function in chronobiology has been provided by recent publications, which are summarised here. Examples of the significance of aquaporins in processes related to chronobiology are given for root water transport and leaf movement in several plant species.     

The NMR study of human biological fluids for detection of pathologies NMR study of biological fluids

The paper deals with the NMR spectra obtained using preparations of five different human biological body fluids. Characteristic metabolite signals of blood, urine, tears, saliva, and sweat spectra have been determined and classified. The biological body fluid samples were used for search and identification of biomarkers of cardiovascular disease. Absolute functional biomarkers for diseases such as coronary heart disease (CHD) have not been recognized even in the case acute myocardial infarction. A hypothesis explaining reasons of lack of such markers has been formulated. The results of comparative analysis of blood and urine samples from humans and some laboratory animals are given. Identify and analyze signals of metabolites of pathogenic microflora and their dynamics in the urine from patients with urogenital diseases have been determined and analyzed and characteristic biomarkers have been recognized.     

Significance of biological parameters of human blood levels of CoQ10

Ninety-one men and 143 women who were so-called normal subjects were tested for cardiac performance at rest and their blood levels of co-enzyme Q10 (CoQ10) were determined. In males, a negative relationship between progression of age and cardiac performance, and a positive relationship between progression of age and blood levels of CoQ10 were revealed. In females, a positive relationship between age and blood levels of CoQ10 was found. The mean CoQ10 blood level for both sexes was the same (0.79 +/- 0.20 micrograms/ml for males and 0.79 +/- 0.23 for females). Cardiac performance declines with age in the male population. A decreased biosynthesis and/or incorporation of CoQ10 into mitochondrial structures of muscle cells may occur with age in a normal population.     

The nature and biological role of near-weekly rhythm

Main peculiarities and possible mechanisms of the rhythms of proliferative activity and other characteristics of the tissue with near-weekly period are discussed. It is suggested that these variations may be explained by means of a simplest model which involves only processes of cell division and death with a delay of division stimulus about 24 hours, which corresponds to the duration of the mitotic cycle. In such a model there are periodic variations of the cell number with the period 4-7 times greater than the delay time.     

Significance of chronotypic specificity of healthy individuals for the variability of cardiac rhythm

Differences in cardiointervalogram parameters have been revealed in young people with the morning and evening chronotypes. Individuals with the morning chronotype are characterized by a tendency to sympathicotonia in the morning, which decreases towards the end of the day. For individuals with the evening chronotype, a reverse tendency is typical, which is manifested as the appearance of signs of cardiointervalogram sympathization in the evening.     

A biometeorology study of climate and heat-related morbidity in Phoenix from 2001 to 2006

Heat waves kill more people in the United States than hurricanes, tornadoes, earthquakes, and floods combined. Recently, international attention focused on the linkages and impacts of human health vulnerability to urban climate when Western Europe experienced over 30,000 excess deaths during the heat waves of the summer of 2003-surpassing the 1995 heat wave in Chicago, Illinois, that killed 739. While Europe dealt with heat waves, in the United States, Phoenix, Arizona, established a new all-time high minimum temperature for the region on July 15, 2003. The low temperature of 35.5 degrees C (96 degrees F) was recorded, breaking the previous all-time high minimum temperature record of 33.8 degrees C (93 degrees F). While an extensive literature on heat-related mortality exists, greater understanding of influences of heat-related morbidity is required due to climate change and rapid urbanization influences. We undertook an analysis of 6 years (2001-2006) of heat-related dispatches through the Phoenix Fire Department regional dispatch center to examine temporal, climatic and other non-spatial influences contributing to high-heat-related medical dispatch events. The findings identified that there were no significant variations in day-of-week dispatch events. The greatest incidence of heat-related medical dispatches occurred between the times of peak solar irradiance and maximum diurnal temperature, and during times of elevated human comfort indices (combined temperature and relative humidity).     

Evidence for biological rhythm in spermatogenesis in the pubertal hamster (Mesocricetus auratus): a flow cytometric study

The number of cells in the S-phase fraction of the cell cycle reflects proliferative activity. Using flow cytometry histograms and the Phoenix M+ cell cycle program, the percent of cells in the S-phase fraction was measured in single cell suspensions prepared from testes of hamsters of different ages. A cyclical pattern with a period of 9 days, superimposed on another rhythm with a 38 day period was observed (p < 0.01) during hamster maturation and it disappeared after the second spermatogenic wave, where the S phase values reached a plateau. It was concluded that maturing animals passed through a stage in which testicular biological rhythm was involved. Therefore it was concluded that it takes approximately two spermatogenic waves before the proliferation rate in the testis reached a steady state.     

A human exposure study to investigate biological monitoring methods for 2-butoxyethanol

2-Butoxyethanol is a glycol ether widely used in printing inks, varnishes and cleaning fluids. As skin absorption can be significant, biological monitoring is useful in monitoring worker exposure. A number of analytes and matrices have been used previously, including 2-butoxyethanol in blood and free and total 2-butoxyacetic acid in urine. Using a combination of a volunteer study and samples from exposed workers, we compared the applicability of some of the biological monitoring markers available. We conclude that 2-butoxyethanol in blood is not a suitable marker for biological monitoring due to sampling problems. In view of the low-level exposures reported in occupational surveys, 2-butoxyethanol in breath is also unsuitable because of a lack of sensitivity. Measuring 2-butoxyacetic acid in blood is possible, although non-invasive urine samples are preferred. Free 2-butoxyacetic acid in urine has previously been widely used; however, we found that the extent of conjugation of 2-butoxyacetic acid in urine varied from 0 to 100% both within and between individuals and is not related to time, concentration or urine pH. Data from 48 exposed workers suggested that an estimated 57% (95% confidence interval 44-70%) of the total 2-butoxyacetic acid is excreted in the conjugated form, and that conjugation may be activated above a certain exposure level. Using total 2-butoxyacetic acid significantly reduced inter-individual variation. Elimination half-lives for free and total 2-butoxyacetic acid were similar (∼6 h) and there was no delay in excretion of the conjugated metabolite (peak excretion for both free and total was between 6 and 12 h after the end of exposure). In conclusion, we propose that total butoxyacetic acid (after acid hydrolysis) in urine is the biomarker of choice for monitoring exposure to 2-butoxyethanol. Urine samples should be collected post-shift towards the end of the working week.