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Ixodes sinensis: competence as a vector to transmit the Lyme disease spirochete Borrelia garinii.

In order to determine the principal vectors of Lyme disease in South China, the capability of Ixodes sinensis to transmit Lyme disease spirochetes transstadially was estimated in the laboratory. Results suggest that I. sinensis can acquire active Lyme disease spirochetes by feeding on infected mice of Kunming strains (KM), and the positive rates of larvae and nymph I. sinensis infected were 94.0% and 92.0%, respectively. I. sinensis maintained active spirochetes during blood digestion and molting periods; the subsequent questing tick stages were also found to be infected and infectious to naiv…

Influence of nutrient deficiency caused by host developmental arrest on the growth and development of a koinobiont parasitoid.

Koinobiont parasitoids utilize nutrients obtained from hosts that contine to feed and grow after parasitization. However, if the ecdysis of early host instars is prevented, parasitized larvae will fail to grow large enough to support the development of the parasitoid brood and both organisms will perish. When L5 instar larvae (the penultimate stage) of Pseudaletia separata were parasitized by Cotesia kariyai and injected with Euplectrus separatae venom (5PV), the development of these hosts was arrested before molting to the next stage and the caterpillars thus failed to gain weight. These host…

Structure-Based Discovery of Potent BCL-XL Inhibitors through Rescaffolding.

Evasion of apoptosis is a hallmark of cancer. Deregulation of BCL-XL, a member of the BCL-2 family of proteins, has been linked to the development of various tumor types. This study presents the design and synthesis of BCL-XL inhibitors with novel mono- and bicyclic cores. The new structural features were optimized to combine high binding efficiency with the opening of diverse novel vectors for additional modifications. The lead compounds exhibited picomolar affinities and significant cellular potency in the BCL-XL-dependent MOLT-4 cell line, which also translated into marked tumor growth inhi

Prolactin-dependent seasonal changes in pelage: role of the pineal gland and dopamine.

The Siberian hamster displays seasonal changes in pelage that are dependent upon fluctuations in circulating prolactin levels. Pinealectomy prevented the decrease in serum prolactin and molt to the winter pelage displayed by castrated males housed under a short-day photoperiod. A dopaminergic antagonist, pimozide, enhanced prolactin levels in both pinealectomized and sham-operated animals under both long and short photoperiods. In the short-day animals, this effect of pimozide was associated with a prevention of the development of winter pelage. These results indicate that seasonal prolactin l

Plant-derived L-asparaginases: Comprehensive functional and biological characterization.

In this study, K-dependent and K-independent plant-derived type III L-asparaginases from Arabidopsis thaliana (AtAIII, AtAIII(K)) and Phaseolus vulgaris (PvAIII, PvAIII(K)-1) were systematically tested for their catalytic properties, structural stability (Tm), and antiproliferative and proapoptotic activity in human leukemia cell lines. Among them, the K-dependent enzyme PvAIII(K)-1 showed the most favorable biological profile, combining high selectivity for L-Asn-dependent MOLT-4 leukemia cells with minimal effects on non-ALL cell lines (RAJI, HL-60, THP-1) and healthy lymphocytes, confirming

Time- and season-dependent changes in the steroidogenic markers in female tree sparrow (Passer montanus).

Seasonal breeders display elevated sex steroid hormone production during reproductive seasons, resulting in significant physiological and structural alterations. One such seasonal breeder adapted to the changing environment is a Tree sparrow (Passer montanus). The study aims to investigate 24-h rhythmicity and annual variations in the expression of steroidogenic gene markers of adult female tree sparrows. Two experiments were conducted; in experiment one, birds (n = 5 birds/time points) were sampled at six time points, i.e., ZT1, ZT5, ZT9, ZT13, ZT17, and ZT21 (ZT = Zeitgeber time, ZT0 = sunri

Comparative Evaluation of the Vector Competence of Four South American Populations of the Rhipicephalus sanguineus Group for the Bacterium Ehrlichia canis, the Agent of Canine Monocytic Ehrlichiosis.

This study compared the vector competence of four populations of Rhipicephalus sanguineus group ticks for the bacterium Ehrlichia canis, the … e) where CME has never been properly documented. Molecular analysis of unfed adults at 30 days post molting support these transmission results, since none of the BRS, ARG, and URU ticks were PCR positive, whereas 1% of the BSP nymphs and 31.8% of the BSP adults contained E. canis DNA. We conclude that the absence or scarcity of cases of CME due to E. cani …

Transcriptome response of a marine copepod in response to environmentally-relevant concentrations of saxitoxin.

Paralytic shellfish toxins (PSTs) can pose a serious threat to human health. Among them, saxitoxin (STX) is one of the most potent natural n … ther cellular processes. STX exposure could inhibit the copepod's chitin metabolism, disrupting its molting process. Also, the processes related to damage repair and protection were up-regulated to fight against high concentration exposure. Collectively, this study has provided an early warning of PSTs for coastal ecosystem not only because of their poten …

Tick hemocytes have a pleiotropic role in microbial infection and arthropod fitness.

Uncovering the complexity of systems in non-model organisms is critical for understanding arthropod immunology. Prior efforts have mostly fo … affects hemocytin and astakine levels, two I. scapularis hemocyte markers, impacting blood-feeding, molting behavior, and bacterial acquisition. Mechanistically, astakine alters hemocyte proliferation, whereas hemocytin affects the c-Jun N-terminal kinase (JNK) signaling pathway in I. scapularis. Altogether, we discover a role for tick hemocytes in immuno …

Total mercury, methylmercury, phosphate, and sulfate inputs to a bog ecosystem from herring gull (Larus smithsoniansus) guano.

Avian biovector transport is an important mechanism for the movement of contaminants and nutrients to remote locations, usually bird colonies, through excretion, molting and decomposition of carcasses. Methylmercury (MeHg) is a bioaccumulative neurotoxin and endocrine disruptor which is present in many remote ecosystems. We collected guano samples biweekly from a herring gull (Larus smithsoniansus) colony over two summers and analyzed MeHg, total mercury (THg), water-extractable phosphate (PO43-) and sulfate (SO42-). Concentrations of THg in guano declined through the summer months while %MeHg…

Population Dynamics of Chewing Lice (Phthiraptera) Infesting Birds (Aves).

In the past 25 years, studies on interactions between chewing lice and their bird hosts have increased notably. This body of work reveals th … usly on their hosts, with seasonal patterns of abundance sometimes related to host reproduction and molting. Competition may have led to spatial partitioning of the host by louse species, but seldom contributes to current patterns of abundance.

Иксодид и аргасидные клещи и западный нильный вирус.

Контроль над вирусом Западного Нила (ВНВ) может быть эффективным только в том случае, если векторы и резервуары вируса будут выявлены и подконтрольны. Хотя основным вектором являются комары, WNV неоднократно отделялся от клещей. Таким образом, исследования по трансмиссии с помощью тикадидов (Ixodes ricinus) и аргасидных клещей (Ornithodoros mubata) проводились с использованием ixodid. Оба вида заразились после того, как питались виремическими носителями, но я. клещи рицина не смогли сохранить вирус. В противоположность этому, клещи О. Мубата были заражены по меньшей мере 132 дня, и инфекция со

Совпадение в аннотации оригинала
Control of West Nile virus (WNV) can only be effective if the vectors and reservoirs of the virus are identified and controlled. Although mo … ast, O. moubata ticks were infected for at least 132 days, and the infection was maintained through molting and a second bloodmeal. Infected O. moubata ticks transmitted the virus to rodent hosts, albeit at a low level. Moreover, the virus was nonsystemically transmitted between infected and uninfected O. moubata ticks co-fed upon uninfected hosts. Althou …

The Function of C-Terminal Pentapeptide in Allatostatin Type-C: Regulating Growth and Development by Affecting Juvenile Hormone Biosynthesis in Ostrinia furnacalis.

Allatostatin Type-C (AstC) is an insect neuropeptide involved in developmental regulation, but whether its conserved C-terminal pentapeptide, PISCF, remains bioactive as an isolated fragment is unclear. Herein, the synthetic PISCF was evaluated on the Asian corn borer, Ostrinia furnacalis, with AstC as a reference. Under sublethal exposure, PISCF suppressed larval growth, reduced relative consumption rate by 47.8-62.5%, impaired nutrient utilization, and modestly advanced molting. It also induced a time-dependent juvenile hormone (JH)-associated response: JH III decreased at 24 h, reached its …

Genome-Wide Identification and functional characterization of chitinase genes in the sorghum aphid (Melanaphis sacchari).

Insect chitinases are integral to a spectrum of vital physiological processes, including growth, development, molting, and metamorphosis. Consequently, chitin metabolic enzymes are potential targets for eco-friendly insecticide development. This study employed bioinformatics approaches to analyze the chitinase gene family in the sorghum aphid(Melanaphis sacchari), identifying seven MsCht genes. Phylogenetic distribution analysis revealed that the chitinases of the sorghum aphid are distributed across multiple clades, and the presence of several orthologous relationships with the pea aphid sugg…

Multigenerational endpoints reveal detrimental effects of tire leachate in the marine mysid Neomysis awatschensis.

Tires generate tire wear particles (TWPs) through abrasion and release complex organic and inorganic compounds via leachates. In this study, … ST, GPx, GR, CAT, and SOD, increased across generations, accompanied by growth retardation, delayed molting, and reduced reproductive output. These findings highlight the potential risks of tire leachate exposure to mysid populations over multiple generations.

Discovery of Sennidin B as a Potent Multitarget Inhibitor of Insect Chitinolytic Enzymes.

Natural products with multitarget inhibitory activity against insect chitinolytic enzymes offer the potential for developing environmentally … his study positions sennidin B as a lead compound for the development of insecticides targeting the molting process and provides a strategy for the discovery of multitarget inhibitors.

Non-canonical Eclosion Hormone-Expressing Cells Regulate Drosophila Ecdysis.

Eclosion hormone (EH) was originally identified as a brain-derived hormone capable of inducing the behavioral sequences required for molting across insect species. However, its role in this process (called ecdysis) has since been confounded by discrepancies in the effects of genetic and cellular manipulations of EH function in Drosophila. Although knock-out of the Eh gene results in severe ecdysis-associated deficits accompanied by nearly complete larval lethality, ablation of the only neurons known to express EH (i.e. Vm neurons) is only partially lethal and surviving adults emerge, albeit ab…

Bursicon-α subunit modulates dLGR2 activity in the adult Drosophila melanogaster midgut independently to Bursicon-β.

Bursicon is the main regulator of post molting and post eclosion processes during arthropod development. The active Bursicon hormone is a heterodimer of Burs-α and Burs-β. However, adult midguts express Burs-α to regulate the intestinal stem cell niche. Here, we examined the potential expression and function of its heterodimeric partner, Burs-β in the adult midgut. Unexpectedly, our evidence suggests that Burs-β is not significantly expressed in the adult midgut. burs-β mutants displayed the characteristic developmental defects but showed wild type-like adult midguts, thus uncoupling the devel…

The Drosophila hugin gene codes for myostimulatory and ecdysis-modifying neuropeptides.

In a genomic screen we isolated the Drosophila gene hugin (hug, cytology 87C1-2) by cross-hybridisation to a human glial cell line-derived n … nd to third instar, suggesting that at least one of the posttranslational cleavage products affects molting of the larva by interfering with the regulation of ecdysis.

Ecdysteroids and oocyte development in the black fly Simulium vittatum.

BACKGROUND: Oocyte development was studied in the autogenous black fly, Simulium vittatum (Diptera, Nematocera), a vector of Onchocerca volv … appearance of vitellogenin in the oocyte, and the rise in ecdysteroids. A possible relationship to molting of the nematode, Onchocerca volvulus, is discussed.