A cohort of 839 young girls at the ages of 14 and 15 years was screened for total antibodies to herpes simplex virus (HSV) and, if positive, for specific antibodies to HSV-2, by means of a sensitive, enzyme-linked immunosorbent assay (ELISA). The cohort was followed from 1972-1987. Blood samples were obtained on six occasions during these 16 years. In total, 2270 blood samples were taken. The number of sero-converting girls was studied in relation to calendar time. Two methods were constructed for the statistical analyses. The first of these gave an estimate of the sero-prevalence at different points in time. This analysis showed that the sero-prevalence which was 23% against HSV-1 in 1972 had increased to 36% in 1976. At the end of the study in 1987, 50% of the cohort had sero-converted against HSV-1. The proportion of girls who had sero-converted against HSV-2 was 0.4% in the 14-15-year-olds and had reached 22% by the end of the study. The second statistical method used all the available information implicit in the observations so as to obtain a maximum-likelihood (ML) estimate of the prevalence. The ML estimates were slightly more precise, but the two estimates did not differ significantly. The observations were further analysed by the Mantel-Haenszel test in order to see if there was any dependence between positivity to HSV-1 and HSV-2 respectively but none was found.
In the summers of 2001 and 2002, we quantitatively sampled human-biting flies in twelve sites located 1.6 to 63 km from a large copper-nickel smelter at Monchegorsk on the Kola Peninsula, Russia. We collected 429 specimens of three species of Ceratopogonidae, 92 specimens of seven species of Culicidae, 76 specimens of seven species of Tabanidae, and 4,788 specimens of 19 species of Simuliidae. Culicoides chiropterus was for the first time reported from the Kola Peninsula. Catches of Culicidae and Simuliidae decreased near the smelter, presumably due to the combined action of toxicity of pollutants, pollution-induced forest damage, and decline in vertebrate density. An abundance of Ceratopogonidae and Tabanidae, the size of the most common black fly species, Simulium pusillum, and the diversity of all families did not change along the pollution gradient.
Perfluorooctane sulfonate (PFOS) is a perfluorinated molecule that has recently been identified in the sera of nonindustrially exposed humans. In this study, 247 tissue samples from 15 species of marine mammals collected from Florida, California, and Alaskan coastal waters; and northern Baltic Sea; the Arctic (Spitsbergen); and Sable Island in Canada were analyzed for PFOS. PFOS was detected in liver and blood of marine mammals from most locations including those from Arctic waters. The greatest concentrations of PFOS found in liver and blood were 1520 ng/g wet wt in a bottlenose dolphin from Sarasota Bay, FL, and 475 ng/mL in a ringed seal from the northern Baltic Sea (Bothnian Sea), respectively. No age-dependent increase in PFOS concentrations in marine mammals was observed in the samples analyzed. The occurrence of PFOS in marine mammals from the Arctic waters suggests widespread global distribution of PFOS including remote locations.
The rate and nocturnal rhythm of mosquito attacks of birds and human beings were studied in the open biotopes of Volgograd and its vicinity in 2004. Thirteen and 11 species of the subfamily Culicinae were collected under the Berezantsev bell and from the traps containing a chicken (a hen), respectively; of them 9 species were common. The mosquitoes of an Anopheles maculipennis complex were caught in a small portion to the traps of both types. Most species of Aedes were highly anthropophilic, showed the minimum activity at night and their abundance considerably decreased by the early transmission period. Among the species that were active during the transmission period, Ae. vexans, Coq. richiardii, and Cx. modestus more intensively attacked a human being than birds and Cx. pipiens was frequently attracted into the hen traps. The attraction of each species of the caught varied during the transmission period. The maximum attacks of Cx. modestus and Cx. pipiens on man and birds coincide and those of Coq. Richiardii and Cx. pipiens on man was observed earlier than on birds. A possible role of mosquitoes of different species in the epizootic and epidemiological processes is discussed.
The North Pacific right whale, Eubalaena japonica, is one of the most endangered species of whale in the world. On 10 August 2004, two right whales were located in the Bering Sea using headings to right whale calls provided by directional sonobuoys. A satellite-monitored radio tag attached to one of these whales functioned for 40 days. Over the 40-day period, this whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer-shelf where right whales have not been seen in decades. In September, multiple right whales were acoustically located and subsequently sighted by another survey vessel approaching a near-real-time position from the tag. An analysis of photographs confirmed at least 17 individual whales (not including the tagged whales). Genetic analysis of biopsy samples identified 17 individuals: 10 males and 7 females. The discovery of seven females was significant, as only one female had been identified in the past. Genetics also confirmed the presence of at least two calves. Although the future of this population is highly uncertain, the discovery of additional females and calves gives some hope that this most critically endangered of all whale populations may still possess the capacity to recover.
Among the waterfowl affected by white phosphorus (P4) at a military base in Alaska are tundra (Cygnus columbianus) and trumpeter (C. buccinator) swans. To estimate the toxicity of P4 to swans and compare the toxic effects to those of mallards (Anas platyrhynchos), we dosed 30 juvenile mute swans (C. olor) with 0 to 5.28 mg P4/kg body weight. The calculated LD50 was 3.65 mg/kg (95% CI: 1.40 to 4. 68 mg/kg). However, many of the swans still had P4 in their gizzards after dying, as determined by "smoking gizzards" and characteristic odor, and a lower LD50 might be calculated if all of the P4 had passed into the small intestines. We attribute the retention of P4 in swans to the possibility that P4 pellets were mistaken for the similarly sized grit in their gizzards. Most swans took 1 to 4.5 days to die in contrast to the few hours normally required in mallards and death appeared to be related more to liver dysfunction than to hemolysis. White phosphorus affected several plasma constituents, most notably elevated aspartate aminotransferase, blood urea nitrogen, lactate dehydrogenase, and alanine aminotransferase.
The genus Drosophila contains over 2,000 species that, stemming from a common ancestor in the Old World Tropics, populate today very different environments [1, 2] (reviewed in ). We found significant differences in the activity pattern of Drosophila species belonging to the holarctic virilis group, i.e., D. ezoana and D. littoralis, collected in Northern Europe, compared to that of the cosmopolitan D. melanogaster, collected close to the equator. These behavioral differences might have been of adaptive significance for colonizing high-latitude habitats and hence adjust to long photoperiods. Most interestingly, the flies' locomotor activity correlates with the neurochemistry of their circadian clock network, which differs between low and high latitude for the expression pattern of the blue light photopigment cryptochrome (CRY) and the neuropeptide Pigment-dispersing factor (PDF) [4-6]. In D. melanogaster, CRY and PDF are known to modulate the timing of activity and to maintain robust rhythmicity under constant conditions [7-11]. We could partly simulate the rhythmic behavior of the high-latitude virilis group species by mimicking their CRY/PDF expression patterns in a laboratory strain of D. melanogaster. We therefore suggest that these alterations in the CRY/PDF clock neurochemistry might have allowed the virilis group species to colonize high-latitude environments.
The adherence of Escherichia coli to human uroepithelial cells obtained from midstream urine specimens of healthy women was studied. Bacteria labeled with [(3)H]uridine were used, and unattached organisms were separated from the epithelial cells by vacuum filtration with 5-mum-pore-size Nucleopore membrane filters. These techniques allowed adherence to be measured in large numbers of epithelial cells and overcame the problem of distinguishing experimental bacteria from the indigenous organisms present on uroepithelial cells. Adherence was not appreciably affected by temperature. Adherence was maximal at pH 4 to 5 and at bacterial-to-epithelial-cell ratios of 5,000 or more. The latter observation suggested that there are a limited number of receptors on the epithelial cell surface, an idea which was supported by competition experiments. Adherence occurred within 1 min and then decreased gradually or quickly, depending on the type of bacterial growth medium, to a stationary level of adherence, approximately 50% of that observed initially. The ability of epithelial cells from a single individual to bind E. coli varied in a cyclical and repetitive pattern. Adherence tended to be higher during the early phase of the menstrual cycle and diminished shortly after the time of expected ovulation; adherence frequently correlated with the value obtained on the same day of the menstrual cycle during the preceding months. Adherence was markedly enhanced by bacterial incubation in broth for 72 h and inhibited by alpha-d-mannose. These results suggest that adherence is a complex phenomenon perhaps mediated in part by bacterial pili and mannose residues on uroepithelial cells.
Cites: J Exp Med. 1977 Nov 1;146(5):1182-9421933
Cites: Infect Immun. 1977 Dec;18(3):767-7422493
Cites: Lancet. 1976 Sep 4;1(7984):490-274461
Cites: Lancet. 1978 Sep 9;2(8089):540-379914
Cites: J Urol. 1975 Aug;114(2):261-3240038
Cites: J Urol. 1977 Apr;117(4):472-6321809
Cites: Nature. 1977 Feb 17;265(5595):623-5323718
Cites: J Urol. 1977 Jul;118(1 Pt 2):221-4327107
Cites: J Urol. 1978 Sep;120(3):315-8355660
Cites: Infect Immun. 1978 Jul;21(1):229-37361565
Cites: Infect Immun. 1978 Oct;22(1):247-54365746
Cites: Appl Environ Microbiol. 1977 Nov;34(5):534-40563215
The lymphoblastic response (LTT) to non-specific mitogens (PHA, PWM and ConA) of peripheral lymphocytes was investigated at days 0, 7, 14, 21 and 28 after adjuvant injection in four strains of inbred rats: Wistar (WAG), Long Evans (LE), Lewis (LEW) and Brown Norway (BN). LTT was assessed by using 18 hours H3 TdR incorporation in 5 days cultures of whole blood (micromethod). The statistical treatment of data, using principal components multifactorial analysis and analysis of variance showed a striking difference between strains. In control animals the responses to PHA and PWM were correlated and were higher in LE and WAG than in LEW and BN (BN=LEW less than LE=WAG). The response to ConA was independent of that to the other mitogens. It was generally low, but significantly higher in LEW and BN than in WAG and LE. In adjuvant-injected animals the responses to PHA and PWM were still correlated, but modified compared to control: in LE and LEW, but not in WAG and BN, a marked decrease of the response was found, reaching a minimum value within days 7 and 14. In the same time the response to ConA increased in the four strains, later in LE than in the others. However the intensity of the ConA response varied from one strain to another: it was constantly low in LE and WAG compared to LEW and BN. So the most striking modification of LTT were observed in LE and LEW, which both developed the most severe arthritis. However these different behaviours after adjuvant injection were not explained by the initial level of LTT to the different mitogens. These data suggest that the development of intense arthritis is associated with the proliferation and the release into the blood stream of a lymphocyte subpopulation, which exhibits a low response to PHA and PWM and a high response to ConA. These LTT modifications are not paralleled by quantitative variations of B-cells assessed by surface Ig immunofluorescent staining and EAC rosetting.