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31.
The vector of Chagas disease, Triatoma infestans, is largely controlled by the household application of pyrethroid insecticides. Because effective, large‐scale insecticide application is costly and necessitates numerous trained personnel, alternative control techniques are badly needed. We compared the residual effect of organophosphate‐based insecticidal paint (Inesfly 5A IGR? (I5A)) to standard deltamethrin, and a negative control, against T. infestans in a simulated natural environment. We evaluated mortality, knockdown, and ability to take a blood meal among 5th instar nymphs. I5A paint caused significantly greater mortality at time points up to nine months compared to deltamethrin (Fisher's Exact Test, p < 0.01 in all instances). A year following application, mortality among nymphs in the I5A was similar to those in the deltamethrin (χ2 = 0.76, df=1, p < 0.76). At months 0 and 1 after application, fewer nymphs exposed to deltamethrin took a blood meal compared to insects exposed to paint (Fisher's Exact Tests, p < 0.01 and p < 0.01, respectively). Insecticidal paint may provide an easily‐applied means of protection against vectors of Chagas disease.  相似文献   
32.
Defects in telomere maintenance genes cause pathological telomere shortening, and manifest in syndromes which have prominent phenotypes in tissues of high turnover: the skin and bone marrow. Because the gastrointestinal (GI) epithelium is highly proliferative, we sought to determine whether telomere syndromes cause GI disease, and to define its prevalence, spectrum, and natural history. We queried subjects in the Johns Hopkins Telomere Syndrome Registry for evidence of luminal GI disease. In sixteen percent of Registry subjects (6 of 38), there was a history of significant GI pathology, and 43 additional cases were identified in the literature. Esophageal stenosis, enteropathy, and enterocolitis were the recurrent findings. In the intestinal mucosa, there was striking villous atrophy, extensive apoptosis, and anaphase bridging pointing to regenerative defects in the epithelial compartment. GI disease was often the first and most severe manifestation of telomere disease in young children. These findings indicate that telomere dysfunction disrupts the epithelial integrity in the human GI tract manifesting in recognizable disease processes. A high index of suspicion should facilitate diagnosis and management.  相似文献   
33.
Abstract

High resolution NMR analysis involving one-dimensional (1-D) 1H and nuclear Overhauser (NOE) difference spectroscopy was applied to solutions of NBMPR in DMSO-d 6. Coupling constants were obtained at different temperatures between 285 and 353 K, and used to analyze the rotamer preferences about the C-4′-C-5′ bond. The results revealed a rotamer distribution about the χ tortion angle that favors the high-anti range, a preponderance of the γ+ rotamer (at ~64 %) with respect to the γ torsion angle, and a higher population of the south (S) conformer, which was favored by as little as the 4 % to as much as 31 % over the north (N) conformer as calculated by the program PSEUROT 6.2. The high-anti glycosidic torsion orientation appears to be the major conformational difference between the solution structure of NBMPR determined in this study and the structure previously observed in the solid state.  相似文献   
34.
The white‐browed woodswallow Artamus superciliosus and masked woodswallow A. personatus (Passeriformes: Artamidae) are members of Australia's diverse arid‐ and semi‐arid zone avifauna. Widely sympatric and among Australia's relatively few obligate long‐distance temperate‐tropical migrants, the two are well differentiated morphologically but not ecologically and vocally. They are pair breeders unlike other Artamus species, which are at least facultative cooperative breeders. For these reasons they are an excellent case in which to use molecular data in integrative study of their evolution from ecological and biogeographical perspectives. We used mitochondrial DNA (mtDNA) to test whether they are each other's closest relatives, whether they evolved migration independently, whether they have molecular signatures of population expansions like some other Australian arid zone birds, and to estimate the timing of any inferred population expansions. Their mtDNAs are monophyletic with respect to other species of Artamus but polyphyletic with respect to each other. The two species appear not to have evolved migration independently of each other but their morphological and mtDNA evolution have been strongly decoupled. Some level of hybridization and introgression cannot be dismissed outright as being involved in their mtDNA polyphyly but incomplete sorting of their most recent common ancestor's mtDNA is a simpler explanation consistent with their ecology. Bayesian phylogenetic inference and analyses of diversity within the two species (n=77) with conventional diversity statistics, statistical parsimony, and tests for population expansion vs stability (Tajima's D, Fu's Fs and Ramos‐Onsin and Rozas's R2) all favour recent population increases. However, a non‐starlike network suggests expansion(s) relatively early in the Pleistocene. Repeated population bottlenecks corresponding with multiple peaks of Pleistocene aridity could explain our findings, which add a new dimension to accruing data on the effects of Pleistocene aridity on the Australian biota.  相似文献   
35.
The placement of Exodontiella Wharton is re-examined in light of the discovery of four additional individuals. Genomic DNA was extracted from one of the individuals, the D2 expansion segment of the 28S rRNA gene was sequenced, and the sequence compared to selected taxa within the Braconidae. Based on the molecular data and the morphological study, Exodontiella is formally transferred from the Opiinae to the Gnamptodontinae. The genus and its included species are redescribed.  相似文献   
36.
Solitary median maxillary central incisor syndrome (SMMCI) is a complex disorder consisting of multiple, mainly midline defects of development resulting from unknown factor(s) operating in utero about the 35th–38th day(s) from conception. It is estimated to occur in 1:50,000 live births. Aetiology is uncertain. Missense mutation in the SHH gene (I111F) at 7q36 may be associated with SMMCI. The SMMCI tooth differs from the normal central incisor, in that the crown form is symmetric; it develops and erupts precisely in the midline of the maxillary dental arch in both primary and permanent dentitions. Congenital nasal malformation (choanal atresia, midnasal stenosis or congenital pyriform aperture stenosis) is positively associated with SMMCI. The presence of an SMMCI tooth can predict associated anomalies and in particular the serious anomaly holoprosencephaly. Common congenital anomalies associated with SMMCI are: severe to mild intellectual disability, congenital heart disease, cleft lip and/or palate and less frequently, microcephaly, hypopituitarism, hypotelorism, convergent strabismus, oesophageal and duodenal atresia, cervical hemivertebrae, cervical dermoid, hypothyroidism, scoliosis, absent kidney, micropenis and ambiguous genitalia. Short stature is present in half the children. Diagnosis should be made by eight months of age, but can be made at birth and even prenatally at 18–22 weeks from the routine mid-trimester ultrasound scan. Management depends upon the individual anomalies present. Choanal stenosis requires emergency surgical treatment. Short stature may require growth hormone therapy. SMMCI tooth itself is mainly an aesthetic problem, which is ideally managed by combined orthodontic, prosthodontic and oral surgical treatment; alternatively, it can be left untreated.  相似文献   
37.
Cluster Computing - The advent of inexpensive data storage has resulted in larger and larger datasets as the cost of pruning data becomes more expensive then storing it for future insights. This...  相似文献   
38.
Biogeochemistry - Dissolved organic matter (DOM) impacts the structure and function of aquatic ecosystems. DOM absorbs light in the UV and visible (UV–Vis) wavelengths, thus impacting light...  相似文献   
39.
Hyaluronan (HA) turnover accelerates metastatic progression of prostate cancer in part by increasing rates of tumor cell proliferation and motility. To determine the mechanism, we overexpressed hyaluronidase 1 (Hyal1) as a fluorescent fusion protein and examined its impact on endocytosis and vesicular trafficking. Overexpression of Hyal1 led to increased rates of internalization of HA and the endocytic recycling marker transferrin. Live imaging of Hyal1, sucrose gradient centrifugation, and specific colocalization of Rab GTPases defined the subcellular distribution of Hyal1 as early and late endosomes, lysosomes, and recycling vesicles. Manipulation of vesicular trafficking by chemical inhibitors or with constitutively active and dominant negative Rab expression constructs caused atypical localization of Hyal1. Using the catalytically inactive point mutant Hyal1-E131Q, we found that enzymatic activity of Hyal1 was necessary for normal localization within the cell as Hyal1-E131Q was mainly detected within the endoplasmic reticulum. Expression of a HA-binding point mutant, Hyal1-Y202F, revealed that secretion of Hyal1 and concurrent reuptake from the extracellular space are critical for rapid HA internalization and cell proliferation. Overall, excess Hyal1 secretion accelerates endocytic vesicle trafficking in a substrate-dependent manner, promoting aggressive tumor cell behavior.  相似文献   
40.
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