Summary Background. Volumetric pollen traps are commonly used to assess pollen exposure. These traps are well suited for estimating the regional mean airborne pollen concentration but are likely not to provide an accurate index of personal exposure. In this study, we tested the hypothesis that hair sampling may provide different pollen counts from those from pollen traps, especially when the po...

During pollen development each product of meiosis undergoes a stereotypical pattern of cell divisions to give rise to a three-celled gametophyte, the pollen grain. First an asymmetric mitosis generates a larger vegetative cell and a smaller generative cell, then the generative cell undergoes a second mitosis to give rise to two sperm cells. It is unknown how this pattern of cell divisions is co...

Pollen from three S-genotypes of Nicotiana alata was grown in vitro in the presence of S-glycoproteins isolated from styles of the same three genotypes. Pollen germination was not affected by the presence of the S-glycoproteins, but pollen tube growth of all genotypes was inhibited. S2 pollen was preferentially inhibited by the S2-glycoprotein and S3 pollen by the S3-glycoprotein. The S6-glycop...

Pollen tubes are an excellent system for studying the cellular dynamics and complex signaling pathways that coordinate polarized tip growth. Although several signaling mechanisms acting in the tip-growing pollen tube have been described, our knowledge on the subcellular and molecular events during pollen germination and growth site selection at the pollen plasma membrane is rather scarce. To si...

Background: There is a rapidly growing trend in the consumption of herbal remedies in the developing countries. The Phoenix dactylifera date palm pollen (DPP) is used in the traditional medicine for male infertility. The aim of this study was to determine the effects of orally administered DPP on the reproductive system of adult male rats. Methods: Fifty Sprague-Dawley rats were maintained acco...

BACKGROUND Beech and oak pollen are potential allergen sources with a world-wide distribution. OBJECTIVE We aimed to characterize the allergen profile of beech and oak pollen and to study cross-reactivities with birch and grass pollen allergens. METHODS Sera from tree pollen-allergic patients with evidence for beech and oak pollen sensitization from Basel, Switzerland, (n=23) and sera from ...

In spite of the low atmospheric pollen levels, Artemisia sensitisation and allergy has been reported widely. The aim of the study was to determine the length of pollen season, intradiurnal, daily and monthly pollen variation, and the effect of some meteorological parameters on atmospheric pollen concentrations in Central Croatia. Seven-day Hirst volumetric pollen and spore traps were used for p...

BACKGROUND AND AIMS Exposure to higher-than-optimal temperatures reduces crop yield and quality, mainly due to sensitivity of developing pollen grains. The mechanisms maintaining high pollen quality under heat-stress conditions are poorly understood. Our recently published data indicate high heat-stress-induced expression of ethylene-responsive genes in tomato pollen, indicating ethylene involv...

Germination ability and airborne counts of Scots pine (Pinus sylvestris L.) pollen were studied during the spring of 1993 at Turku in southern Finland (60 degrees 32' N, 22 degrees 28' E) and at Utsjoki in northern Finland (69 degrees 45' N, 27 degrees 01' E). Pollen waas trapped from the beginning of May to the end of June in a high-volume air sampler. Germination tests were performed to deter...