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41.
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While recent imaging techniques provide insights into biological processes from the molecular to the cellular scale, phenotypes at larger scales remain poorly amenable to quantitative analyses. For example, investigations of the biophysical mechanisms generating skin morphological complexity and diversity would greatly benefit from 3D geometry and colour-texture reconstructions. Here, we report on R2OBBIE-3D, an integrated system that combines a robotic arm, a high-resolution digital colour camera, an illumination basket of high-intensity light-emitting diodes and state-of-the-art 3D-reconstruction approaches. We demonstrate that R2OBBIE generates accurate 3D models of biological objects between 1 and 100 cm, makes multiview photometric stereo scanning possible in practical processing times, and enables the capture of colour-texture and geometric resolutions better than 15 μm without the use of magnifying lenses. R2OBBIE has the potential to greatly improve quantitative analyses of phenotypes in addition to providing multiple new applications in, e.g., biomedical science.  相似文献   
43.
Accumulation of beta amyloid (Aβ) in the brain is a primary feature of Alzheimer’s disease (AD) but the exact molecular mechanisms by which Aβ exerts its toxic actions are not yet entirely clear. We documented pathological changes 3 and 6 months after localised injection of recombinant, bi-cistronic adeno-associated viral vectors (rAAV2) expressing human Aβ40-GFP, Aβ42-GFP, C100-GFP or C100V717F-GFP into the hippocampus and cerebellum of 8 week old male mice. Injection of all rAAV2 vectors resulted in wide-spread transduction within the hippocampus and cerebellum, as shown by expression of transgene mRNA and GFP protein. Despite the lack of accumulation of Aβ protein after injection with AAV vectors, injection of rAAV2-Aβ42-GFP and rAAV2- C100V717F-GFP into the hippocampus resulted in significantly increased microgliosis and altered permeability of the blood brain barrier, the latter revealed by high levels of immunoglobulin G (IgG) around the injection site and the presence of IgG positive cells. In comparison, injection of rAAV2-Aβ40-GFP and rAAV2-C100-GFP into the hippocampus resulted in substantially less neuropathology. Injection of rAAV2 vectors into the cerebellum resulted in similar types of pathological changes, but to a lesser degree. The use of viral vectors to express different types of Aβ and C100 is a powerful technique with which to examine the direct in vivo consequences of Aβ expression in different regions of the mature nervous system and will allow experimentation and analysis of pathological AD-like changes in a broader range of species other than mouse.  相似文献   
44.
Anthonomus grandis, the cotton boll weevil, causes severe cotton crop losses in North and South America. Here we demonstrate the presence of starch in the cotton pollen grains and young ovules that are the main A. grandis food source. We further demonstrate the presence of α-amylase activity, an essential enzyme of carbohydrate metabolism for many crop pests, in A. grandis midgut. Two α-amylase cDNAs from A. grandis larvae were isolated using RT-PCR followed by 5′ and 3′ RACE techniques. These encode proteins with predicted molecular masses of 50.8 and 52.7 kDa, respectively, which share 58% amino acid identity. Expression of both genes is induced upon feeding and concentrated in the midgut of adult insects. Several α-amylase inhibitors from plants were assayed against A. grandis α-amylases but, unexpectedly, only the BIII inhibitor from rye kernels proved highly effective, with inhibitors generally active against other insect amylases lacking effect. Structural modeling of Amylag1 and Amylag2 showed that different factors seem to be responsible for the lack of effect of 0.19 and α-AI1 inhibitors on A. grandis α-amylase activity. This work suggests that genetic engineering of cotton to express α-amylase inhibitors may offer a novel route to A. grandis resistance.  相似文献   
45.
Biological Trace Element Research - Excessive adipose tissue promotes the manifestation of endocrine disorders such as reduction of the secretion of zinc-α2-glycoprotein (ZAG), an adipokine...  相似文献   
46.
BackgroundThis study evaluates an active search strategy for leprosy diagnosis based on responses to a Leprosy Suspicion Questionnaire (LSQ), and analyzing the clinical, immunoepidemiological and follow-up aspects for individuals living in a prison population.MethodsA cross-sectional study based on a questionnaire posing 14 questions about leprosy symptoms and signs that was distributed to 1,400 prisoners. This was followed by dermatoneurological examination, anti-PGL-I serology and RLEP-PCR. Those without leprosy were placed in the Non-leprosy Group (NLG, n = 1,216) and those diagnosed with clinical symptoms of leprosy were placed in the Leprosy Group (LG, n = 34).FindingsIn total, 896 LSQ were returned (64%), and 187 (20.9%) of the responses were deemed as positive for signs/symptoms, answering 2.7 questions on average. Clinically, 1,250 (89.3%) of the prisoners were evaluated resulting in the diagnosis of 34 new cases (LG), based on well-accepted clinical signs and symptoms, a new case detection rate of 2.7% within this population, while the NLG were comprised of 1,216 individuals. The confinement time medians were 39 months in the LG while it was 36 months in the NLG (p>0.05). The 31 leprosy cases who responded to the questionnaire (LSQ+) had an average of 1.5 responses. The symptoms “anesthetized skin area” and “pain in nerves” were most commonly mentioned in the LG while “tingling, numbness in the hands/feet”, “sensation of pricks and needles”, “pain in nerves” and “spots on the skin” responses were found in more than 30% of questionnaires in the NLG. Clinically, 88.2% had dysesthetic macular skin lesions and 97.1% presented some peripheral nerve impairment, 71.9% with some degree of disability. All cases were multibacillary, confirming a late diagnosis. Anti-PGL-I results in the LG were higher than in the NLG (p<0.0001), while the RLEP-PCR was positive in 11.8% of the patients.InterpretationOur findings within the penitentiary demonstrated a hidden prevalence of leprosy, although the individuals diagnosed were likely infected while living in their former communities and not as a result of exposure in the prison. The LSQ proved to be an important screening tool to help identify leprosy cases in prisons.  相似文献   
47.

Upper limb nerve injuries are common, and their treatment poses a challenge for physicians and surgeons. Experimental models help in minimum exploration of the functional characteristics of peripheral nerve injuries of forelimbs. This study was conducted to characterize the functional recovery (1, 3, 7, 10, 14, and 21 days) after median and ulnar nerve crush in mice and analyze the histological and biochemical markers of nerve regeneration (after 21 days). Sensory–functional impairments appeared after 1 day. The peripheral nerve morphology, the nerve structure, and the density of myelin proteins [myelin protein zero (P0) and peripheral myelin protein 22 (PMP22)] were analyzed after 21 days. Cold allodynia and fine motor coordination recovery occurred on the 10th day, and grip strength recovery was observed on the 14th day after injury. After 21 days, there was partial myelin sheath recovery. PMP22 recovery was complete, whereas P0 recovery was not. Results suggest that there is complete functional recovery even with partial remyelination of median and ulnar nerves in mice.

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48.
Sockeye salmon (Oncorhynchus nerka) is one of the most iconic and valued species of Pacific salmon. Various studies have examined the potential effects of future climate change on sockeye salmon, but there is currently no synthesis of the documented effects of climate on this species. In this paper, we present a synthesis of 80 peer-reviewed publications in the English language evaluating the effects of climate on sockeye salmon growth, phenology, and survival. The great majority of studies examined have been conducted with stocks from North America (90?% of studies). Survival (55?%) has been the most frequently studied aspect of the sockeye salmon life history in relation to climate, followed by growth (45?%) and phenology (30?%), with temperature (83.4?%) being the climate-related variable most frequently examined in such studies. Across life stages, the effects of climate-related variables have been most frequently studied on fry (36.3?%) and least studied on spawners (7.5?%). Our synthesis revealed that associations between temperature and growth, phenology, or survival have been uncovered for all the life stages of sockeye salmon, whereas relationships with other climate-related variables have been sparse. There is substantial evidence that sockeye salmon are influenced by thermal conditions experienced at regional, rather than ocean- or continental-wide scales, and that responses to temperature vary among and within stocks. The mechanisms by which climate affect sockeye salmon during the early stages in freshwater and while at sea are still poorly understood and warrant future research. More research on the effects of non-temperature, climate-related variables (e.g. stream flow, ocean pH), inter-generational and carry-over effects of climate, interaction between climate and non-climate stressors, and adaptation to climate change are also needed. Such information will be critical to advance our understanding of how sockeye salmon stocks will fare with future climate change.  相似文献   
49.
A novel approach to DNase I-sensitivity analysis was applied to examining genes of the spermatogenic pathway, reflective of the substantial morphological and genomic changes that occur during this program of differentiation. A new real-time PCR-based strategy that considers the nuances of response to nuclease treatment was used to assess the nuclease susceptibility through differentiation. Data analysis was automated with the K-Lab PCR algorithm, facilitating the rapid analysis of multiple samples while eliminating the subjectivity usually associated with Ct analyses. The utility of this assay and analytical paradigm as applied to nuclease-sensitivity mapping is presented.  相似文献   
50.
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