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Research on water mites has mainly focused on their ecology, taxonomy and faunistics. Studies on the biology of particular species and their fecundity have been conducted much less often, and there is very little such information from the Balkan Peninsula. The present study attempts to fill in some of the gaps in the existing knowledge upon reproduction of water mites. Female individuals were collected from Lake Skadar and its catchment in Montenegro, in May and October 2014. Then they were placed in 40 ml beakers until eggs were laid and observed until the larvae were hatched. The eggs were laid by females representing 15 species. The numbers of egg-laying females of a given species ranged from 1 to 124. The average number of eggs laid by a female ranged from 1 to 60. The number of eggs laid in May was much higher than in October. Females which lays the most eggs (representing 9 species) were collected in springs, followed by Lake Skadar (7 species) and in rivers (4 species). Only one species, Hygrobates setosus, was encountered in all types of waters studied, two species were encountered in the lake and in springs (Lebertia ineaqualisand Fiona disparilis), and one (Hygrobates fluviatilis)in springs and in rivers. In general, the highest numbers of eggs were laid by females from rivers, followed by those from springs and from the lake. The average time of embryonic development ranged from 9 days (Hydrochoreutes kramert)to 20 days (Atractides fonticulusand Protzia eximia), while the total incubation period ranged from 9 to 30 days. It seems that the water mites laid higher number of eggs in the spring than in the autumn. Hatching time depends on the temperature. The number of eggs laid by one female is characteristic of the species or genus.

Research on water mites has mainly focused on their ecology, taxonomy and faunistics. Studies on the biology of particular species and their fecundity have been conducted much less often, and there is very little such information from the Balkan Peninsula. The present study attempts to fill in some of the gaps in the existing knowledge upon reproduction of water mites. Female individuals were collected from Lake Skadar and its catchment in Montenegro, in May and October 2014. Then they were placed in 40 ml beakers until eggs were laid and observed until the larvae were hatched. The eggs were laid by females representing 15 species. The numbers of egg-laying females of a given species ranged from 1 to 124. The average number of eggs laid by a female ranged from 1 to 60. The number of eggs laid in May was much higher than in October. Females which lays the most eggs (representing 9 species) were collected in springs, followed by Lake Skadar (7 species) and in rivers (4 species). Only one species, Hygrobates setosus, was encountered in all types of waters studied, two species were encountered in the lake and in springs (Lebertia ineaqualisand Piona disparilis), and one (Hygrobates fluviatilis) in springs and in rivers. In general, the highest numbers of eggs were laid by females from rivers, followed by those from springs and from the lake. The average time of embryonic development ranged from 9 days (Hydrochoreutes krameri) to 20 days (Atractides fonticulusand Protzia eximia), while the total incubation period ranged from 9 to 30 days. It seems that the water mites laid higher number of eggs in the spring than in the autumn. Hatching time depends on the temperature. The number of eggs laid by one female is characteristic of the species or genus.

Telomere length (TL) measurement is central to many biomedical research, population, and epidemiology studies, with promising potential as a clinical tool. Various assays are used to determine TL, depending on the type and size of the sample. We describe the detailed optimization of a monochromatic multiplex real-time quantitative PCR (MMqPCR) assay for relative TL using the LightCycler 480. MMqPCR was initially developed using a different instrument with many separate reagents. Differences in instrument performance, reagents, and workflow required substantial optimization for the assay to be compatible with the LightCycler 480. We optimized the chemistry of the assay using a purchased one-component reaction mix and herein describe sources of variability and quality control relevant to the MMqPCR TL assay on any instrument. Finally, the assay was validated against other TL assays, such as terminal restriction fragment, Southern blot, and flow fluorescent in situhybridization. The correlations obtained between data from MMqPCR and these assays (R2 = 0.88 and 0.81) were comparable to those seen with the monoplex version (R2 = 0.85 and 0.82) when the same samples were assayed. The intrarun and interrun CV ranged from 4.2% to 6.2% and 3.2% to 4.9%, respectively. We describe a protocol for measuring TL on the LightCycler platform that provides a robust high-throughput method applicable to clinical diagnostics or large-scale studies of archived specimens.

We present the first data from Poland concerning parasitism of Hydrachnidia on Chironomidae. Larvae of Hygrobatessp., H. setosus, Unionicola aculeataand Piona stjoerdalensiswere found attached to adult Chironomidae (Cricotopus triannulatus, Tanytarsussp., Paratanytarsussp., Critocopussp. and Orthocladiussp.). Intensity of infestation ranged between 1 to 2 larvae. All of the parasites were attached to abdomens of the hosts. The determination of parasitism of U. aculeataon Paratanytarsusand Tanytarsusgenera extends the list of the hosts of this water mite species to the mentioned genera of Chironomidae. In case of H. setosus, the parasitism of this water mite on currently known hosts from the family Chironomidae has been confirmed.

We present the first data from Poland concerning parasitism of Hydrachnidia on Chironomidae. Larvae of Hygrobates sp., H. setosus, Unionicola aculeata and Piona stjoerdalensis were found attached to adult Chironomidae (Cricotopus triannulatus, Tanytarsus sp., Paratanytarsus sp., Critocopus sp. and Orthocladius sp.). Intensity of infestation ranged between 1 to 2 larvae. All of the parasites were attached to abdomens of the hosts. The determination of parasitism of U. aculeata on Paratanytarsus and Tanytarsus genera extends the list of the hosts of this water mite species to the mentioned genera of Chironomidae. In case of H. setosus, the parasitism of this water mite on currently known hosts from the family Chironomidae has been confirmed.

Nucleo(st)ide reverse transcriptase inhibitors given to HIV-infected pregnant women to prevent vertical transmission may adversely affect mitochondrial DNA (mtDNA). We hypothesized that HAART-exposedHIV-uninfected infants may show higher blood mtDNA mutation burden than controls born to HIV-uninfected mothers.

Background Tenofovir (TDF) exposure has been associated with renal dysfunction. Mitochondrial nephrotoxicity was investigated as an underlying mechanism. Given the interaction between TDF and didanosine (ddI), their concurrent use was also investigated.Design Relative kidney biopsy mitochondrial DNA (mtDNA) to nuclear DNA ratios were measured retrospectively. HIV+individuals on TDF within 6 months preceeding the biopsy (HIV+/TDF+, n=21) were compared to HIV+individuals who never received TDF (HIV+/TDF-, n=10) and to HIV uninfected controls (HIV–,n=22). Twelve of the HIV+/TDF+individuals received concurrent ddI, 10 of those once at unadjusted ddI dosage. Tubular mitochondria morphology was also examined by electron microscopy. Statistical analyses were done on log-transformed mtDNA/nDNA, using non-parametric tests.Results Kidney mtDNA levels were different among the three groups (P=0.046). mtDNA ratios were lower in HIV+/TDF+subjects (7.5 [2.0–12.1]) than in HIV-ones (14.3 [6.0–16.5], P=0.014), but not lower than HIV+/TDF-controls (6.4 [2.8–11.9], P=0.82). Among HIV+subjects, there was a difference between TDF-, TDF+/ddI-and TDF+/ddI+(P=0.005), with concurrent TDF/ddI use associated with lower mtDNA (2.1 [1.9–5.5], n=12) than TDF+/ddI-(13.8 [7.5–16.4], n=9, P=0.003). No TDF–/ddI+biopsies were available. In regression analyses, only HIV infection (P=0.03), and TDF/ddI use (P=0.003) were associated with lower mtDNA. At the ultrastructural level, abnormal tubular mitochondria was more prevalent in HIV+/TDF+biopsies than HIV+/TDF-and HIV-ones together (P<0.001) but not more so in TDF+/ddI+biopsies than TDF+/ddI-ones (P=0.67).Conclusions Renal dysfunction in this population may be mediated through mitochondrial nephrotoxicity that involves more than one drug and/or pathogenesis. Kidney mtDNA depletion was associated with HIV infection and concurrent TDF/ddI therapy but not TDF use alone, while kidney ultrastructural mitochondrial abnormalities were seen with TDF use. The interaction between TDF and ddI may be relevant in the kidney where both drugs are cleared. The clinical relevance of our findings needs to be evaluated given the current recommendation for reduced doses of ddI when used in conjunction with TDF.

Studies were done in Manitoba, Canada, to evaluate the impact of exercise on repellent performance against mosquitoes. Two products containing the active ingredient N,N-diethyl-3-methylbenzamide (deet) were tested; one product was a polymer-based cream (3M Ultrathon Insect Repellent) and the other product was an alcohol-based pump spray formulation (Muskol Insect Repellent). Assessments were done in the laboratory using Aedes aegypti (L.) and in the field with naturally occurring populations of mosquitoes. Repellent was applied to the forearms (laboratory) or a lower leg (field) of test subjects at 1.5 g of test product per 600 cm2 surface area (0.75 or 0.83 mg deet/cm2). For a given test day, subjects exercised or did not. Exposure to mosquito attack was for 1 min at 30-min intervals in laboratory procedures, and it was continuous in field tests. Performance was measured as complete protection time (CPT). Moderate levels of physical activity resulted in a >40% decline in mean CPT, from 468 to 267 min in the laboratory experiments and from 359 to 203 min in field tests. Repellent product did not affect the magnitude of the decline. Mean biting pressure during field trials was 21.3 bites per min, and mosquito collections were made up primarily of Ochlerotatus sticticus (Meigen) and Aedes vexans (Meigen).

Studies were carried out in Manitoba, Canada, to evaluate the efficacy of three repellent products for protection of human subjects against mosquito bites. All test substances contained the active ingredient N,N-diethyl-3-methylbenzamide (deet); two were polymer-based creams (3M Ultrathon Insect Repellent and Morflex DEET Insect Repellent 30) and the third (Muskol Insect Repellent) was an alcohol-based pump spray formulation. Application of repellent was to the forearm and lower legs of subjects at 0.75 or 0.83 mg deet/cm2. Exposure to mosquito attack was continuous, and efficacy was determined by measuring complete protection time (CPT). Regardless of whether delivered as a polymer cream or in alcohol, mean CPT was similar for the tested repellents at 623 ± 107 to 644 ± 163 min. By contrast, mean CPT for the different test subjects showed significant variation, ranging from 531 ± 42 to 756 ± 54 min. Mosquito collections from untreated human test subjects, Centers for Disease Control and Prevention (CDC) light traps and sweep-netting consisted primarily of Ochlerotatus sticticus (Meigen) and Aedes vexans (Meigen). Relative catch of these two species was similar for different sampling methods through much of the day, but not in the evening, when CDC light traps oversampled Ae. vexans relative to untreated human subjects. Results are used to highlight the need to account for intersubject variation when designing repellent studies, and also are used as a basis to discuss limitations associated with using relatively few subjects when testing repellents.

Gonotrophic-age structure of a population of Aedes provocans (Walker) and nectar sources used by adults were studied for 2 yr at a field site near Belleville, Ontario, Canada. Females emerged during a short period, and aging of the population was highly synchronous. Complete parity of the population was achieved within about 17 d in 1978 and 27 d in 1979. Some females completed as many as four gonotrophic cycles. This synchronous pattern of population aging is compared with patterns in other species of snow-melt Aedes, which typically age much more gradually. The pattern of synchronous aging permitted estimation of daily mortality rates from an index of population size derived from human-bait catches; peaks in the biting index were related to each gonotrophic cycle in the population. Nectar sources for adults were ranked according to abundance and the extent to which they were used by Ae. provocans, permitting a coarse, semiquantitative estimate of preferences. Ae. provocans obtained nectar from the extrafloral nectaries of one species and the floral nectaries of 19 species of angiosperms. Shrubs and trees, especially of the Rosaceae (primarily species of Prunus), were particularly important as nectar sources and bloomed concurrently with the appearance of nulliparous females. Sharp declines in the population of Ae. provocans were associated with the cessation of blooming of these plant species. It is hypothesized that the highly synchronous pattern of gonotrophic aging in Ae. provocans was attributable, in part, to the ready availability of nectar sources and bloodmeal hosts near breeding sites.