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1.
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year.  相似文献   
2.
As an early stage of plant transformation by Agrobacterium tumefaciens, the Ti plasmid is nicked at the border sequences that delimit the T-DNA. Cleavage results in covalent attachment of VirD2 to the 5' terminal of the nicked strand by a process resembling initiation of DNA transfer that occurs in the donor cell during bacterial conjugation. We demonstrate that this cleavage can be reproduced in vitro: VirD2 protein, the border-cleaving enzyme, was overproduced and purified. Cleavage assays were performed with single-stranded oligodeoxyribonucleotides encompassing the Ti plasmid border region or the transfer origin's nick region of the conjugative plasmid RP4. VirD2 of pTiC58 cleaves both border- and nick region-containing oligonucleotides. However, the relaxase TraI of RP4 can cut only the cognate nick regions. The respective proteins remain covalently bound to the 5' end of the cleavage sites, leaving the 3' termini unmodified. VirD2-mediated oligonucleotide cleavage was demonstrated to be an equilibrium reaction that allows specific joining of cleavage products restoring border and nick regions, respectively. The possible role of VirD2 in T-DNA integration into the plant cell's genome is discussed in terms of less stringent target-sequence requirements.  相似文献   
3.
4.

Introduction  

Combined aortic and mitral valve disease is usually of rheumatic origin. In these patients we often encounter problem of small valve annuli particularly with aortic annulus. It is still debated whether a small prosthesis should be used or aortic root should be enlarged to prevent Patient Prosthesis Mismatch (PPM). This study was undertaken to review our strategy and feasibility of Aortic Root Enlargement (ARE) in patient undergo Double Valve Replacement (DVR) to avoid mismatch without increase in cost of treatment, morbidity or mortality.  相似文献   
5.
The IncP antibiotic-resistance plasmids transfer to a broad range of bacterial species. The RK2 origin of DNA transfer (oriT) consists of a 250-base-pair segment including the single-stranded cleavage site (nic) needed to generate the DNA strand believed to be transferred. Deletion derivatives and a bank of hydroxylamine-generated oriT mutants were screened for loss of transferability. DNA regions flanking both sides of nic are required for optimal transfer of the oriT clone. Of the chemically induced mutants, critical base-pair changes that dramatically reduced transfer frequency were found in a 10-base-pair region adjacent to nic. Relaxation (nicking) assays performed with these point mutants using protein-DNA complexes reconstituted in vitro revealed a correlation between DNA nicking and transfer frequency. Base-pair changes within the proximal arm of an inverted repeat upstream from the nick site resulted in reduced binding of the essential transfer protein TraJ and correspondingly reduced transfer frequencies. The results support a model of relaxosome formation involving at least two essential proteins: TraI and TraJ. The nick region defined by the point mutants was located in a segment known to be nearly identical in the related plasmid R751. This sequence was also found to be highly conserved in both border junctions of the transfer DNA (T-DNA) of plant tumor-inducing plasmids of Agrobacterium tumefaciens, indicating a relationship between IncP-mediated broad-host-range bacterial conjugation and T-DNA transfer to plants.  相似文献   
6.
When performing a tooth extraction, imminent collapse of the tissue by resorption and remodeling of the socket is a natural occurrence. The procedure for the preservation of the alveolar ridge has been widely described in the dental literatures and aims to maintain hard and soft tissues in the extraction site for optimal rehabilitation either with conventional fixed or removable prosthetics or implant-supported prosthesis.  相似文献   
7.

Introduction and hypothesis

Our goal was to determine psychosexual outcome after labiaplasty in the long-term with specific measures of genital body image and sexual dysfunction.

Method

We conducted a prospective study with a matched-comparison group of women not wanting labiaplasty. Forty-nine women were compared against a group of 39 women matched for age, sexual orientation, ethnicity, and marital status. The labiaplasty group was assessed before, 3 months after and between 11 and 42 months after surgery. The comparison group was assessed at two time points 3 months apart to control for the passage of time. The primary outcome measure was the Genital Appearance Satisfaction (GAS) scale.

Results

Of the 49 women receiving labiaplasty, 19 (38.8 %) were lost to follow-up but were reassessed clinically. Twenty-four of 25 (96 %) women in the labiaplasty group showed a reliable and clinically significant improvement on the GAS scale 3 months after the procedure; 21/23 (91.3 %) showed an improvement at the long-term follow-up. A large effect size was found for improvements on the GAS scale in the labiaplasty group. Small-effect sizes were found for improvements in sexual functioning. Nine women obtaining labiaplasty met diagnostic criteria for body dysmorphic disorder before the operation; eight lost that diagnosis at the 3-month follow-up; 26 % reported minor side effects.

Conclusions

Labiaplasty is effective in improving genital appearance and sexual satisfaction, but larger studies are required to determine the prevalence of potential side effects.  相似文献   
8.

Introduction and hypothesis

We present the cohort of 33 women who underwent botulinum toxin type A (BTX-A) injections examining the efficacy and safety of BTX-A in idiopathic detrusor overactivity (IDO). The aim of this report is to describe the outcomes of those who underwent repeated injections of BTX-A.

Methods

All 33 women had 3 or more injections with an initial dose of 500 units of Dysport® with subsequent injections between 500 and 750 U, administered by the classic trigone-sparing flexible/rigid cystoscopic technique. An informed consent was obtained in all cases. Efficacy was measured using voiding diaries and quality of life (QOL) assessed with the International Consultation on Incontinence Questionnaire-Short Form (ICIQ -SF). This project was approved by the Clinical Effectiveness Department and the Drugs and Therapeutics Committee (DTC). Therefore, ethical approval was not required.

Results

This study included 33 women who have been successfully treated with repeated intradetrusor injections of BTX-A (Dysport®). Mean duration between the first and second injections was 15.2?±?7.2 months, whereas between the second and third was 19.2?±?10 months (P?=?0.025). Two women developed urinary tract infection and required clean intermittent self-catheterization. Three women required dose escalation to 750 units. Longer duration of subjective QOL improvement was noted between the second and third botulinum toxin injections compared to duration between the first and second injections.

Conclusions

BTX-A appears to be effective and safe after repeated administration in women with IDO. The duration of the injection tends to get prolonged after the second injection.  相似文献   
9.
A thymoma in the neck region is a rare diagnosis involving a solitary neck nodule that moves with deglutition and is contiguous with the thyroid gland. The authors report an unusual case of a thymoma that accumulated both Tc-99m pertechnetate and Tc-99m MIBI. This is probably the first reported case of a benign neck thymoma concentrating these two radiopharmaceuticals. Thymoma should be added to the gamut of false-positive findings in the neck for thyroidal (with Tc-99m pertechnetate) and malignant (with Tc-99m MIBI) tissue.  相似文献   
10.
RP4 TrbB, an essential component of the conjugative transfer apparatus of the broad-host-range plasmid RP4, is a member of the PulE protein superfamily involved in multicomponent machineries transporting macromolecules across the bacterial envelope. PulE-like proteins share several well conserved motifs, most notable a nucleoside triphosphate binding motif (P-loop). Helicobacter pylori HP0525 also belongs to the PulE superfamily and is encoded by the pathogenicity island cag, involved in the inflammatory response of infected gastric epithelial cells in mammals. The native molecular masses of TrbB and HP0525 as determined by gel filtration and glycerol gradient centrifugation suggested a homohexameric structure in the presence of ATP and Mg(2+). In the absence of nucleotides and bivalent cations, TrbB behaved as a tetramer whereas the hexameric state of HP0525 remained unaffected. Electron microscopy and image processing demonstrated that TrbB and HP0525 form ring-shaped complexes (diameter: 12 nm) with a central region (diameter: 3 nm) of low electron density when incubated in the presence of ATP and Mg(2+). However, the TrbB average image appeared to be more elliptical with strong twofold rotational symmetry whereas HP0525 complexes are regular hexagons. Six well defined triangle-shaped areas of high electron density were distinguishable in both cases. Covalent crosslinking of TrbB suggests that the hexameric ring is composed from a trimer of dimers, because only dimeric, tetrameric, and hexameric species were detectable. The toroidal structure of TrbB and HP0525 suggests that both proteins catalyze a repetitive process, most probably translocating a cognate substrate across the inner membrane.  相似文献   
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