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81.
Gingold-Belfer Rachel Levy Sigal Layfer Olga Pakanaev Lea Niv Yaron Dickman Ram Perets Tsachi Tsadok 《Probiotics and antimicrobial proteins》2020,12(1):112-118
Probiotics and Antimicrobial Proteins - Lactose intolerance is a common condition caused by lactase deficiency and may result in symptoms of lactose malabsorption (bloating, flatulence, abdominal... 相似文献
82.
Sura Shayna A. Delgadillo Aaron Franco Nancy Gu Kelly Turba Rachel Fong Peggy 《Coral reefs (Online)》2019,38(3):425-429
Coral Reefs - Closely cropped algal turfs are characteristic of healthy coral reefs, but unchecked growth can cause transitions into long sediment-laden turfs, which may be an alternative degraded... 相似文献
83.
Rachel L Dannenberg Joseph A Cardina Kara G Pytko Mark Hedglin 《Nucleic acids research》2022,50(17):9893
During DNA replication, DNA lesions in lagging strand templates are initially encountered by DNA polymerase δ (pol δ) holoenzymes comprised of pol δ and the PCNA processivity sliding clamp. These encounters are thought to stall replication of an afflicted template before the lesion, activating DNA damage tolerance (DDT) pathways that replicate the lesion and adjacent DNA sequence, allowing pol δ to resume. However, qualitative studies observed that human pol δ can replicate various DNA lesions, albeit with unknown proficiencies, which raises issues regarding the role of DDT in replicating DNA lesions. To address these issues, we re-constituted human lagging strand replication to quantitatively characterize initial encounters of pol δ holoenzymes with DNA lesions. The results indicate pol δ holoenzymes support dNTP incorporation opposite and beyond multiple lesions and the extent of these activities depends on the lesion and pol δ proofreading. Furthermore, after encountering a given DNA lesion, subsequent dissociation of pol δ is distributed around the lesion and a portion does not dissociate. The distributions of these events are dependent on the lesion and pol δ proofreading. Collectively, these results reveal complexity and heterogeneity in the replication of lagging strand DNA lesions, significantly advancing our understanding of human DDT. 相似文献
84.
Santos R Mariano AC Rosas-Oliveira R Pascarelli B Machado EA Meyer-Fernandes JR Gondim KC 《Archives of insect biochemistry and physiology》2008,67(2):55-62
The processes of accumulation and mobilization of carbohydrate stores in eggs of Rhodnius prolixus were analyzed. During oogenesis, the total amounts of glycogen, glucose, and trehalose increased with an accumulation of proteins, especially when oocytes grew from 1.0 to 1.5 mm in length. At 2.0 mm length, when oocytes were ready for oviposition, nutrient reserves did not increase appreciably and trehalose content decreased. Mating did not affect the final content of carbohydrates or proteins in oocytes of mated and virgin females. A trehalase activity was detected in follicles containing vitellogenic oocytes, 1.0 and 1.5 mm length, in both mated and virgin females. This activity was extremely low in chorionated, 2.0-mm oocytes. After oviposition, glycogen content decreased in fertilized eggs, but not in unfertilized ones, and some was present in newly hatched nymphs. Glucose content remained constant in unfertilized eggs, but increased in fertilized ones, while total protein amount was constant in both groups after egg laying. 相似文献
85.
Ruben Attali Sharon Aharoni Susan Treves Ori Rokach Michal Becker Cohen Yakov Fellig Rachel Straussberg Talya Dor Muhannad Daana Stella Mitrani-Rosenbaum Yoram Nevo 《PloS one》2013,8(7)
We describe an autosomal recessive heterogeneous congenital myopathy in a large consanguineous family. The disease is characterized by variable severity, progressive course in 3 of 4 patients, myopathic face without ophthalmoplegia and proximal muscle weakness. Absence of cores was noted in all patients. Genome wide linkage analysis revealed a single locus on chromosome 19q13 with Zmax = 3.86 at θ = 0.0 and homozygosity of the polymorphic markers at this locus in patients. Direct sequencing of the main candidate gene within the candidate region, RYR1, was performed. A novel homozygous A to G nucleotide substitution (p.Y3016C) within exon 60 of the RYR1 gene was found in patients. ARMS PCR was used to screen for the mutation in all available family members and in an additional 150 healthy individuals. This procedure confirmed sequence analysis and did not reveal the A to G mutation (p.Y3016C) in 300 chromosomes from healthy individuals. Functional analysis on EBV immortalized cell lines showed no effect of the mutation on RyR1 pharmacological activation or the content of intracellular Ca2+ stores. Western blot analysis demonstrated a significant reduction of the RyR1 protein in the patient’s muscle concomitant with a reduction of the DHPRα1.1 protein. This novel mutation resulting in RyR1 protein decrease causes heterogeneous clinical presentation, including slow progression course and absence of centrally localized cores on muscle biopsy. We suggest that RYR1 related myopathy should be considered in a wide variety of clinical and pathological presentation in childhood myopathies. 相似文献
86.
Ryan Greenway Rachel McNemee Alexander Okamoto Martin Plath Lenin Arias‐Rodriguez Michael Tobler 《Evolution; international journal of organic evolution》2019,73(6):1200-1212
Divergence of genital traits among lineages has the potential to serve as a reproductive isolating barrier when copulation, insemination, and fertilization are inhibited by incompatibilities between female and male genitalia. Despite widespread evidence for genital trait diversity among closely related lineages and coevolution of female and male genitalia within lineages, few studies have investigated genital evolution during the early stages of speciation. We quantified genital variation in replicated population pairs of Poecilia mexicana with ongoing ecological speciation between sulfidic (H2S containing) and nearby nonsulfidic habitats. These analyses revealed rapid and correlated divergence of female and male genitalia across evolutionarily independent population pairs exposed to divergent selection regimes. Both sexes exhibited convergent evolution of genital traits among populations inhabiting similar habitat types. Our results demonstrate that genital evolution can occur during the early stages of speciation‐with‐gene‐flow, potentially as a result of variation in the intensity of sexual conflict among populations. Our results suggest genitalia may contribute to early stages of divergence and challenge the generality of previously suggested mechanisms of genital evolution in poeciliids. 相似文献
87.
Pupo Amaury Ayers Michael C. Sherman Zachary N. Vance Rachel J. Cumming Jonathan R. Gallagher Jennifer E. G. 《Biological trace element research》2020,195(1):260-271
Biological Trace Element Research - While drugs and other industrial chemicals are routinely studied to assess risks, many widely used chemicals have not been thoroughly evaluated. One such... 相似文献
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Vector-borne diseases are of global importance to human and animal health. Empirical trials of effective methods to control
vectors and their pathogens can be difficult for practical, financial and ethical reasons. Here, therefore, we use a mathematical
model to predict the effectiveness of a vector-borne disease control method. As a case study, we use the tick-louping ill
virus system, where sheep are treated with acaricide in an attempt to control ticks and disease in red grouse , an economically
important game bird. We ran the model under different scenarios of sheep flock sizes, alternative host (deer) densities, acaricide
efficacies and tick burdens. The model predicted that, with very low deer densities, using sheep as tick mops can reduce the
tick population and virus prevalence. However, treatment is ineffective above a certain threshold deer density, dependent
on the comparative tick burden on sheep and deer. The model also predicted that high efficacy levels of acaricide must be
maintained for effective tick control. This study suggests that benignly managing one host species to protect another host
species from a vector and pathogen can be effective under certain conditions. It also highlights the importance of understanding
the ecological complexity of a system, in order to target control methods only under certain circumstances for maximum effectiveness. 相似文献