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101.
102.
J. Baron E. Fishbourne E. Couacy‐Hyman M. Abubakar B. A. Jones L. Frost R. Herbert T. R. Chibssa G. van't Klooster M. Afzal C. Ayebazibwe P. Toye J. Bashiruddin M. D. Baron 《Transboundary and Emerging Diseases》2014,61(5):390-396
We have developed an immunochromatographic test for the diagnosis of peste des petits ruminants (PPR) under field conditions. The diagnostic assay has been tested in the laboratory and also under field conditions in Ivory Coast, Pakistan, Ethiopia and Uganda. The test is carried out on a superficial swab sample (ocular or nasal) and showed a sensitivity of 84% relative to PCR. The specificity was 95% over all nasal and ocular samples. The test detected as little as 103 TCID50 (50% tissue culture infectious doses) of cell culture‐grown virus, and detected virus isolates representing all four known genetic lineages of peste des petits ruminants virus. Virus could be detected in swabs from animals as early as 4 days post‐infection, at a time when clinical signs were minimal. Feedback from field trials was uniformly positive, suggesting that this diagnostic tool may be useful for current efforts to control the spread of PPR. 相似文献
103.
Mia C. Hikke Stine Braaen Stephane Villoing Kjartan Hodneland Corinne Geertsema Lisa Verhagen Petter Frost Just M. Vlak Espen Rimstad Gorben P. Pijlman 《Vaccine》2014
Salmonid alphavirus (SAV; also known as Salmon pancreas disease virus; family Togaviridae) causes pancreas disease and sleeping disease in Atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. SAV infection in vivo is temperature-restricted and progeny virus is only produced at low temperatures (10–15 °C). Using engineered SAV replicons we show that viral RNA replication is not temperature-restricted suggesting that the viral structural proteins determine low-temperature dependency. The processing/trafficking of SAV glycoproteins E1 and E2 as a function of temperature was investigated via baculovirus vectors in Sf9 insect cells and by transfection of CHSE-214 fish cells with DNA constructs expressing E1 and E2. We identified SAV E2 as the temperature determinant by demonstrating that membrane trafficking and surface expression of E2 occurs only at low temperature and only in the presence of E1. Finally, a vaccination-challenge model in Atlantic salmon demonstrates the biological significance of our findings and shows that SAV replicon DNA vaccines encoding E2 elicit protective immunity only when E1 is co-expressed. This is the first study that identifies E2 as the critical determinant of SAV low-temperature dependent virion formation and defines the prerequisites for induction of a potent immune response in Atlantic salmon by DNA vaccination. 相似文献
104.
Yasmeen M. Byrnes Neil N. Luu Ariel S. Frost Tiffany N. Chao Robert M. Brody Steven B. Cannady Karthik Rajasekaran Rabie M. Shanti Jason G. Newman 《世界耳鼻咽喉头颈外科杂志(英文)》2022,8(4):302
ObjectiveTo evaluate medical student and attending surgeon experiences with a novel interactive virtual Otolaryngology ‐ Head and Neck Surgery (OHNS) medical student elective during the COVID‐19 pandemic.Study DesignA virtual OHNS elective was created, with three components: (1) interactive virtual operating room (OR) experience using live‐stream video‐conferencing, (2) telehealth clinic, (3) virtual didactics.SettingOHNS Department at the University of Pennsylvania (May 2020 to June 2020).MethodsSix medical students from the University of Pennsylvania; five attending otolaryngologists. Two surveys were designed and distributed to participating medical students and attending surgeons. Surveys included 5‐point Likert scale items, with 1 indicating “not at all” and 5 indicating “very much so”.ResultsResponse rate was 100% for both surveys. Students on average rated the educational value of the telehealth experience as 4.2 ± 1.2, and the virtual OR experience as 4.0 ± 0.6. Most students (n = 5, 83%) indicated that they had enough exposure to faculty they met on this rotation to ask for a letter of recommendation (LOR) for residency if needed, while attending surgeons had an average response of 3.0 ± 1.0 when asked how comfortable they would feel writing a LOR for a student they met through the rotation. A majority of students (n = 4, 67%) felt they connected enough with faculty during the rotation to ask for mentorship. Half the students (n = 5, 50%) indicated that the rotation allowed them to evaluate the department''s culture either “extremely well” or “somewhat well”.ConclusionsOverall, participating students described this innovative virtual surgical rotation as an educationally and professionally valuable experience. With the continued suspension of visiting student rotations due to the COVID‐19 pandemic, this virtual model may have continued relevance to medical education. 相似文献
105.
Human T-cell leukemia virus type I isolates from Gabon and Ghana: comparative analysis of proviral genomes 总被引:4,自引:0,他引:4
M Fukasawa H Tsujimoto K Ishikawa T Miura B Ivanoff R W Cooper E Frost E Delaporte J A Mingle F C Grant 《Virology》1987,161(2):315-320
Two isolates of human T-cell leukemia virus type I (HTLV-I) were obtained from lymphocyte cultures of a healthy carrier in Gabon and another in Ghana. Their proviruses were analyzed by Southern blot hybridization and compared with prototypical HTLV-I isolated in Japan and the United States. The provirus genomes of both strains were highly homologous to the prototype HTLV-I along the whole viral genome. The restriction endonuclease sites of the Ghanian isolate were almost identical with those of the prototype HTLV-I, but 10 of 26 sites of the Gabonese isolate were different from those of the prototype. Furthermore, the restriction map of the Gabonese isolate resembled those of a simian T-cell leukemia virus (STLV-I) isolated from a chimpanzee from Sierra Leone and a variant of HTLV-I from Zaire (HTLV-Ib) more closely than those of any other known HTLV-I. These results indicated the existence of some unique strains of HTLV-I transmitted among African people, and the importance of clarifying the origin and transmission of HTLV group viruses. 相似文献
106.
Phage 18, a noninducible coliphage, is quite unstable and therefore difficult to study. Newly developed very gentle lysis and mounting techniques yielded isolated virions for examination by electron microscopy. The phage has a contractile tail with a length of 130 nm and an isometric head with a capsid diameter of 50 nm. Phage 18 is similar in morphology to phage P2 but is heteroimmune to it. DNA extracted from a clear-plaque mutant of phage 18 was subjected to BamHI restriction endonuclease digestion and was found to be easily distinguishable from the published restriction patterns for P2, phage 299, or phage 186 DNA. The genome size was calculated to be 33.5 kb. Using the DNA melting point, phage 18 DNA (G+C) content was determined to be 55.0% and its buoyant density was determined to be 1.715. 相似文献
107.
108.
This study was undertaken to explore the motivations and problems shared by adult orthognathic surgical patients over the age of 25. Objective findings included demographic information and reasons for seeking surgery. The majority of 65 respondents cited functional problems as their primary reason for seeking treatment. Eighty-nine percent were pleased with esthetic changes, and 83% responded that the functional problem had been corrected. For most, the greatest discomfort related to the surgery was the postoperative intensive care unit. Two of the most common side effects of the surgery were the loss of sensation in the lips and chin area and a short period of depression. Women had depression more often than men but were more enthusiastic about the final results of the procedure. Two major areas of interest to surgeons emerged from the research. First, although women have functional problems, the majority seem to have a desire for cosmetic improvement. Having a functional problem seemed to provide the psychological permission necessary to spend the time and money for a cosmetic change. The second point focused on the need for good communication between surgeon and patient. The patients who were more positive toward the procedure and more satisfied with the results were those who were better informed and who thought they had a good system of communication with the orthodontist, surgeon, and their respective staffs. 相似文献
109.
Peter G. Passias Cyrus M. Jalai Breton G. Line Gregory W. Poorman Justin K. Scheer Justin S. Smith Christopher I. Shaffrey Douglas C. Burton Kai-Ming G. Fu Eric O. Klineberg Robert A. Hart Frank Schwab Virginie Lafage Shay Bess 《The spine journal》2018,18(2):234-244
Background Context
Non-operative management is a common initial treatment for patients with adult spinal deformity (ASD) despite reported superiority of surgery with regard to outcomes. Ineffective medical care is a large source of resource drain on the health system. Characterization of patients with ASD likely to elect for operative treatment from non-operative management may allow for more efficient patient counseling and cost savings.Purpose
This study aimed to identify deformity and disability characteristics of patients with ASD who ultimately convert to operative treatment compared with those who remain non-operative and those who initially choose surgery.Study Design/Setting
A retrospective review was carried out.Patient Sample
A total of 510 patients with ASD (189 non-operative, 321 operative) with minimum 2-year follow-up comprised the patient sample.Outcome Measures
Oswestry Disability Index (ODI), Short-Form 36 Health Assessment (SF-36), Scoliosis Research Society questionnaire (SRS-22r), and spinopelvic radiographic alignment were the outcome measures.Methods
Demographic, radiographic, and patient-reported outcome measures (PROMs) from a cohort of patients with ASD prospectively enrolled into a multicenter database were evaluated. Patients were divided into three treatment cohorts: Non-operative (NON=initial non-operative treatment and remained non-operative), Operative (OP=initial operative treatment), and Crossover (CROSS=initial non-operative treatment with subsequent conversion to operative treatment). NON and OP groups were propensity score-matched (PSM) to CROSS for baseline demographics (age, body mass index, Charlson Comorbidity Index). Time to crossover was divided into early (<1?year) and late (>1?year). Outcome measures were compared across and within treatment groups at four time points (baseline, 6 weeks, 1 year, and 2 years).Results
Following PSM, 118 patients were included (NON=39, OP=38, CROSS=41). Crossover rate was 21.7% (41/189). Mean time to crossover was 394 days. All groups had similar baseline sagittal alignment, but CROSS had larger pelvic incidence and lumbar lordosis (PI-LL) mismatch than NON (11.9° vs. 3.1°, p=.032). CROSS and OP had similar baseline PROM scores; however, CROSS had worse baseline ODI, PCS, SRS-22r (p<.05). At time of crossover, CROSS had worse ODI (35.7 vs. 27.8) and SRS Satisfaction (2.6 vs. 3.3) compared with NON (p<.05). Alignment remained similar for CROSS from baseline to conversion; however, PROMs (ODI, PCS, SRS Activity/Pain/Total) worsened (p<.05). Early and late crossover evaluation demonstrated CROSS-early (n=25) had worsening ODI, SRS Activity/Pain at time of crossover (p<.05). From time of crossover to 2-year follow-up, CROSS-early had less SRS Appearance/Mental improvement compared with OP. Both CROSS-early/late had worse baseline, but greater improvements, in ODI, PCS, SRS Pain/Total compared with NON (p<.05). Baseline alignment and disability parameters increased crossover odds—Non with Schwab T/L/D curves and ODI≥40 (odds ratio [OR]: 3.05, p=.031), and Non with high PI-LL modifier grades (“+”/‘++’) and ODI≥40 (OR: 5.57, p=.007) were at increased crossover risk.Conclusions
High baseline and increasing disability over time drives conversion from non-operative to operative ASD care. CROSS patients had similar spinal deformity but worse PROMs than NON. CROSS achieved similar 2-year outcome scores as OP. Profiling at first visit for patients at risk of crossover may optimize physician counseling and cost savings. 相似文献110.
Gene disruption of p27(Kip1) allows cell proliferation in the postnatal and adult organ of corti 总被引:12,自引:0,他引:12 下载免费PDF全文
Löwenheim H Furness DN Kil J Zinn C Gültig K Fero ML Frost D Gummer AW Roberts JM Rubel EW Hackney CM Zenner HP 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(7):4084-4088
Hearing loss is most often the result of hair-cell degeneration due to genetic abnormalities or ototoxic and traumatic insults. In the postembryonic and adult mammalian auditory sensory epithelium, the organ of Corti, no hair-cell regeneration has ever been observed. However, nonmammalian hair-cell epithelia are capable of regenerating sensory hair cells as a consequence of nonsensory supporting-cell proliferation. The supporting cells of the organ of Corti are highly specialized, terminally differentiated cell types that apparently are incapable of proliferation. At the molecular level terminally differentiated cells have been shown to express high levels of cell-cycle inhibitors, in particular, cyclin-dependent kinase inhibitors [Parker, S. B., et al. (1995) Science 267, 1024-1027], which are thought to be responsible for preventing these cells from reentering the cell cycle. Here we report that the cyclin-dependent kinase inhibitor p27(Kip1) is selectively expressed in the supporting-cell population of the organ of Corti. Effects of p27(Kip1)-gene disruption include ongoing cell proliferation in postnatal and adult mouse organ of Corti at time points well after mitosis normally has ceased during embryonic development. This suggests that release from p27(Kip1)-induced cell-cycle arrest is sufficient to allow supporting-cell proliferation to occur. This finding may provide an important pathway for inducing hair-cell regeneration in the mammalian hearing organ. 相似文献