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81.
Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L4). Also, the resistance of MuLL to digestion by L4 gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L4 gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L4 with LC50 of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L4 gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference in the activity of digestive larval enzymes.  相似文献   
82.
83.
El‐Hattab AW, Bournat J, Eng PA, Wu JBS, Walker BA, Stankiewicz P, Cheung SW, Brown CW. Microduplication of Xp11.23p11.3 with effects on cognition, behavior, and craniofacial development. We report an ~1.3 Mb tandem duplication at Xp11.23p11.3 in an 11‐year‐old boy with pleasant personality, hyperactivity, learning and visual‐spatial difficulties, relative microcephaly, long face, stellate iris pattern, and periorbital fullness. This clinical presentation is milder and distinct from that of patients with partially overlapping Xp11.22p11.23 duplications which have been described in males and females with intellectual disability, language delay, autistic behaviors, and seizures. The duplicated region harbors three known X‐linked mental retardation genes: FTSJ1, ZNF81, and SYN1. Quantitative polymerase chain reaction from whole blood total RNA showed increased expression of three genes located in the duplicated region: EBP, WDR13, and ZNF81. Thus, over‐expression of genes in the interval may contribute to the observed phenotype. Many of the features seen in this patient are present in individuals with Williams‐Beuren syndrome (WBS). Interestingly, the SYN1 gene within the duplicated interval, as well as the STX1A gene, within the WBS critical region, co‐localize to presynaptic active zones, and play important roles in neurotransmitter release.  相似文献   
84.
This paper introduces a new paradigm in the study of emotional processes through functional neuroimaging. We study whether the valence and arousal of visual stimuli influence neuroimaging of the evoked hemodynamic changes. Using functional near-infrared spectroscopy (fNIRS), we investigate evoked-cerebral blood oxygenation (CBO) changes in dorsolateral prefrontal cortex (DLPFC) during direct exposure to different emotion-eliciting stimuli ('on' period), and during the period directly following stimulus cessation ('off' period). We hypothesize that the evoked-CBO, rather than return to baseline after stimulus cessation, would show either overshoot or undershoot. The study includes 30 healthy subjects and a total of 9 stimuli, which consist of video-clips with different emotional content. The total sample of trials studied (270) is classified according to the valence and arousal ratings given by the subjects. Results show a more robust activation in DLPFC during the 'off' period than during the 'on' period, depending on the subjective degree of arousal given to the stimulus. Our findings provide the first fNIRS evidence showing that an increment in subjective arousal leads to activation in DLPFC which persists after stimulus cessation and this does not occur with non-arousing stimuli. Neuroimaging studies must consider the duration and affective dimensions of the stimulus as well as the duration of the scanning to specify how much of the recorded response is analyzed. Not accounting for this difference may contribute to confusion in the data interpretation.  相似文献   
85.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
86.
The objectives of this cross-sectional observational study were: (i) to detect DNA damage and plasma membrane translocation of phosphatidylserine in purified sperm populations of high and low motility, and (ii) to analyse their relationship with the endogenous generation of reactive oxygen species. Ejaculates from infertile men were examined following gradient centrifugation. The main outcome measures were: sperm motion parameters (assessed with a computer analyser), generation of reactive oxygen species (measured by chemiluminescence), DNA damage (detected by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling and monoclonal antibody labelling of single-stranded DNA) and translocation of membrane phosphatidylserine (examined with annexin V staining). DNA fragmentation and membrane translocation of phosphatidyl-serine were observed in the fractions with low and high sperm motility in all patients. The fractions with low sperm motility had significantly higher proportion of cells with DNA damage and production of reactive oxygen species than the fractions with high sperm motility (P < 0.005). DNA fragmentation was significantly and positively correlated with the generation of reactive oxygen species (r = 0.42; P = 0.02). In conclusion: (i) spermatozoa from infertile men display translocation of membrane phosphatidylserine as diagnosed by annexin V positive staining; (ii) DNA damage (fragmentation and presence of single-stranded DNA) can be detected in ejaculated spermatozoa from infertile men in fractions with low and high sperm motility, and (iii) there is a relationship between DNA damage and oxidative stress.  相似文献   
87.
Objectives: To screen for potentially underreported behavioral changes in patients with idiopathic Parkinson's disease (PD) pre‐ and post‐deep brain stimulation (DBS), a retrospective data base review was performed. Methods: In total, 113 patients who underwent unilateral or bilateral DBS at the University of Florida in either subthalamic nucleus or globus pallidus internus for PD were screened for behavioral issues by asking about the presence or absence of seven neuropsychiatric symptoms (panic, fear, paranoia, anger, suicidal flashes, crying, and laughing). Results: There was a high prevalence of fear (16.3%), panic (14.0%), and anger (11.6%) at baseline in this cohort. In the first six months following DBS implantation, anger (32.6%), fear (26.7%), and uncontrollable crying (26.7%) were the most frequent symptoms reported. Those symptoms also were present following six months of DBS surgery (30.2%, 29.1%, and 19.8%, respectively). New uncontrollable crying occurred more in the acute postoperative stage (less than or equal to six months) (p= 0.033), while new anger occurred more in the chronic postoperative stage (greater than six months) (p= 0.017). The frequency of uncontrollable laughing significantly increased with bilateral DBS (p= 0.033). Conclusions: Many of the neuropsychiatric issues were identified at preoperative baseline and their overall occurrence was more than expected. There was a potential for worsening of these issues post‐DBS. There were subtle differences in time course, and in unilateral vs. bilateral implantations. Clinicians should be aware of these potential behavioral issues that may emerge following DBS therapy, and should consider including screening questions in preoperative and postoperative interviews. Standardized scales may miss the presence or absence of these clinically relevant issues.  相似文献   
88.
Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial...  相似文献   
89.
正ISBN-10:0081015151ISBN-13:978-0081015155Woodhead出版社2018年11月出版2版724页本书是Woodhead出版社生物技术系列丛书中的一册,这一全新版本由国际临床专家与研究人员合作编纂,为材料学家及工程师、药剂师、临床工作者以及本领域研究人员提供最新参考信息。本书第一部分介绍关节置换技术、摩擦学观点及其实验、术后免疫与再生反应等方面的进展;第二部分涵盖关节置换相关材料与技术,阐明  相似文献   
90.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population.  相似文献   
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