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71.

SUMMARY

Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism.  相似文献   
72.
The ubiquitin–proteasome system (UPS) is the primary pathway responsible for the recognition and degradation of misfolded, damaged, or tightly regulated proteins in addition to performing essential roles in DNA repair, cell cycle regulation, cell migration, and the immune response. While traditional biochemical techniques have proven useful in the identification of key proteins involved in this pathway, the implementation of novel reporters responsible for measuring enzymatic activity of the UPS has provided valuable insight into the effectiveness of therapeutics and role of the UPS in various human diseases such as multiple myeloma and Huntington’s disease. These reporters, usually consisting of a recognition sequence fused to an analytical handle, are designed to specifically evaluate enzymatic activity of certain members of the UPS including the proteasome, E3 ubiquitin ligases, and deubiquitinating enzymes. This review highlights the more commonly used reporters employed in a variety of scenarios ranging from high-throughput screening of novel inhibitors to single cell microscopy techniques measuring E3 ligase or proteasome activity. Finally, a recent study is presented highlighting the development of a novel degron-based substrate designed to overcome the limitations of current reporting techniques in measuring E3 ligase and proteasome activity in patient samples.  相似文献   
73.
The discovery that genetic mutations in several cellular pathways can increase lifespan has lent support to the notion that pharmacological inhibition of aging pathways can be used to extend lifespan and to slow the onset of age‐related diseases. However, so far, only few compounds with such activities have been described. Here, we have conducted a chemical genetic screen for compounds that cause the extension of chronological lifespan of Schizosaccharomyces pombe. We have characterized eight natural products with such activities, which has allowed us to uncover so far unknown anti‐aging pathways in S. pombe. The ionophores monensin and nigericin extended lifespan by affecting vacuolar acidification, and this effect depended on the presence of the vacuolar ATPase (V‐ATPase) subunits Vma1 and Vma3. Furthermore, prostaglandin J2 displayed anti‐aging properties due to the inhibition of mitochondrial fission, and its effect on longevity required the mitochondrial fission protein Dnm1 as well as the G‐protein‐coupled glucose receptor Git3. Also, two compounds that inhibit guanosine monophosphate (GMP) synthesis, mycophenolic acid (MPA) and acivicin, caused lifespan extension, indicating that an imbalance in guanine nucleotide levels impinges upon longevity. We furthermore have identified diindolylmethane (DIM), tschimganine, and the compound mixture mangosteen as inhibiting aging. Taken together, these results reveal unanticipated anti‐aging activities for several phytochemicals and open up opportunities for the development of novel anti‐aging therapies.  相似文献   
74.
Abstract

The emergence of tumour recurrence and resistance limits the survival rate for most tumour-bearing patients. Only, combination therapies targeting pathways involved in the induction and in the maintenance of cancer growth and progression might potentially result in an enhanced therapeutic efficacy. Herein, we provided a prospective combination treatment that includes suberoylanilide hydroxamic acid (SAHA), a well-known inhibitor of histone deacetylases (HDACs), and SLC-0111, a novel inhibitor of carbonic anhydrase (CA) IX. We proved that HDAC inhibition with SAHA in combination with SLC-0111 affects cell viability and colony forming capability to greater extent than either treatment alone of breast, colorectal and melanoma cancer cells. At the molecular level, this therapeutic regimen resulted in a synergistically increase of histone H4 and p53 acetylation in all tested cell lines. Overall, our findings showed that SAHA and SLC-0111 can be regarded as very attractive combination providing a potential therapeutic strategy against different cancer models.  相似文献   
75.
Shock wave lithotripsy is a commonly used procedure for eradicating upper urinary tract stones in patients who require treatment. A number of methods have been proposed to improve the results of this procedure, including proper patient selection, modifications in technique, adjunctive therapy to facilitate elimination of fragments, and changes in lithotripter design. This article assesses the utility of these measures through an analysis of contemporary literature.Key Words: Shock wave lithotripsy, Upper urinary tract stones, ComminutionShock wave lithotripsy (SWL) is commonly utilized to treat patients with upper urinary tract stones. It is now clear that proper patient selection, modifications in treatment technique, and employment of adjunctive measures can be utilized to optimize SWL results. In addition, certain future changes in lithotripter design may prove to be beneficial. Herein, we review methods to improve SWL results.  相似文献   
76.
SAS-6 is required for centriole biogenesis in diverse eukaryotes. Here, we describe a novel family of SAS-6-like (SAS6L) proteins that share an N-terminal domain with SAS-6 but lack coiled-coil tails. SAS6L proteins are found in a subset of eukaryotes that contain SAS-6, including diverse protozoa and green algae. In the apicomplexan parasite Toxoplasma gondii, SAS-6 localizes to the centriole but SAS6L is found above the conoid, an enigmatic tubulin-containing structure found at the apex of a subset of alveolate organisms. Loss of SAS6L causes reduced fitness in Toxoplasma. The Trypanosoma brucei homolog of SAS6L localizes to the basal-plate region, the site in the axoneme where the central-pair microtubules are nucleated. When endogenous SAS6L is overexpressed in Toxoplasma tachyzoites or Trypanosoma trypomastigotes, it forms prominent filaments that extend through the cell cytoplasm, indicating that it retains a capacity to form higher-order structures despite lacking a coiled-coil domain. We conclude that although SAS6L proteins share a conserved domain with SAS-6, they are a functionally distinct family that predates the last common ancestor of eukaryotes. Moreover, the distinct localization of the SAS6L protein in Trypanosoma and Toxoplasma adds weight to the hypothesis that the conoid complex evolved from flagellar components.  相似文献   
77.
78.
Mobility is crucial for the maintenance of viable metapopulations, but quantitative data to evaluate risks due to insufficient individual mobility of focal insect species are mostly lacking. We selected the butterfly Brenthis ino, a species typically confined to wet fallow grasslands in Central Europe and performed a mark–release–recapture study in a 3.2 ha study area with one big and one small patch of suitable habitat from 22 June to 23 July 2010. The position of each butterfly capture was measured with a GPS and transferred into a GIS. In total, we marked 984 individuals in 1,545 capture events and estimated that the cumulative population size was 2,400 individuals. The initial increase of adult males proceeded much faster than for females, similar to the protandrous population build-up known from other butterflies. Moved distances for both sexes usually did not exceed 80 m, and about 40 % of all individuals used less than 2 % of the available suitable habitat. All individuals switching to the other patch returned later to their patch of origin, confirming that B. ino is highly philopatric. We conclude that low effective mobility in B. ino produces much smaller home ranges than suggested by merely observing flight activities in the field, and that low tendencies towards long-distance movements significantly hamper the maintenance of metapopulations when patch density decreases due to landscape fragmentation.  相似文献   
79.
Biosolids result from treatment of sewage sludge to meet jurisdictional standards, including pathogen reduction. Once government regulations are met, materials can be applied to agricultural lands. Culture-based methods are used to enumerate pathogen indicator microorganisms but may underestimate cell densities, which is partly due to bacteria existing in a viable but non-culturable physiological state. Viable indicators can also be quantified by real-time polymerase chain reaction (qPCR) used with propidium monoazide (PMA), a dye that inhibits amplification of DNA found extracellularly or in dead cells. The objectives of this study were to test an optimized PMA-qPCR method for viable pathogen detection in wastewater solids and to validate it by comparing results to data obtained by conventional plating. Reporter genes from genetically marked Pseudomonas sp. UG14Lr and Agrobacterium tumefaciens 542 cells were spiked into samples of primary sludge, and anaerobically digested and Lystek-treated biosolids as cell-free DNA, dead cells, viable cells, and mixtures of live and dead cells, followed by DNA extraction with and without PMA, and qPCR. The protocol was then used for Escherichia coli quantification in the three matrices, and results compared to plate counts. PMA-qPCR selectively detected viable cells, while inhibiting signals from cell-free DNA and DNA found in membrane-compromised cells. PMA-qPCR detected 0.5–1 log unit more viable E. coli cells in both primary solids and dewatered biosolids than plate counts. No viable E. coli was found in Lystek-treated biosolids. These data suggest PMA-qPCR may more accurately estimate pathogen cell numbers than traditional culture methods.  相似文献   
80.
Adherence to medication among individuals with chronic obstructive pulmonary disease (COPD) is suboptimal and has negative impacts on survival and health care costs. No systematic review has examined the effectiveness of interventions designed to improve medication adherence. Electronic databases Medline and Cochrane were searched using a combination of MeSH and keywords. Eligible studies were interventions with a primary or secondary aim to improve medication adherence among individuals with COPD published in English. Included studies were assessed for methodological quality using the Effective Practice and Organisation of Care (EPOC) criteria. Of the 1,186 papers identified, seven studies met inclusion criteria. Methodological quality of the studies was variable. Five studies identified effective interventions. Strategies included: brief counselling; monitoring and feedback about inhaler use through electronic medication delivery devices; and multi-component interventions consisting of self-management and care co-ordination delivered by pharmacists and primary care teams. Further research is needed to establish the most effective and cost effective interventions. Special attention should be given to increasing patient sample size and using a common measure of adherence to overcome methodological limitations. Interventions that involve caregivers and target the healthcare provider as well as the patient should be further explored.  相似文献   
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