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1.
Meiosis was examined in pollen mother cells of F1 hybrids made from crosses between wheat (Triticum aestivum) and lymegrass (Leymus arenarius and L. mollis). Fluorescence genomic in situ hybridization detected pairing between wheat and lymegrass chromosomes during prophase I and metaphase I. Such pairing, when resulting in bivalent formation, was likely to yield correct disjunction, and hence intergenomic recombination could be incorporated into the gametes. Bivalents in these hybrids, however, were more frequently formed between chromosomes of the same parental origin. Univalents were common, whereas multivalents were not clearly detected. Meiotic behaviour in some cells was not totally aberrant, and this may have accounted for the presence of normal pollen. The results are discussed in relation to intergenomic pairing, meiotic behaviour in wide-hybrids and genome relationships, including the Leymus genome origin.  相似文献   
2.
During the epidemic caused by maedi-visna virus (MVV) of sheep in Iceland, the pulmonary affection, maedi, was the predominant clinical manifestation. In some flocks, however, a central nervous system (CNS) affection, visna, was the main cause of morbidity and mortality. As there is only one breed of sheep in the country, host factors did apparently not play an important role in the different clinical manifestations. To obtain some information on possible viral genetic determinants of neurotropism and neurovirulence we studied both phenotypic and genotypic properties of two maedi-visna virus strains; a strain that was originally isolated from the brain of sheep with encephalitis (visna), and another strain isolated from the lungs of a sheep suffering from pneumonia (maedi). The brain isolate was found to grow faster in sheep choroid plexus cells than the lung isolate, whereas the growth rate in macrophages was similar for the maedi and visna virus strains. Intracerebral inoculation indicated that the visna virus isolate induced more severe brain lesions than the maedi isolate. In addition, a pathogenic molecular clone derived from a visna strain (KV1772kv72/67) was tested for growth in sheep choroid plexus cells and macrophages. The molecularly cloned virus retained the fast growth rate in choroid plexus cells. The nucleotide sequence of the env gene and the U3 of the LTR was determined for the maedi strain and compared to that of the visna strains. There was an 11.7% difference in deduced amino acid sequence in the Env protein and a 6% difference in the LTR. The molecular clone KV1772kv72/67 will be a useful reagent for characterization of viral determinants of cell tropism in vitro and possibly neurovirulence in vivo. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
3.
Objective. To evaluate the rectal mucosal response to gluten as an indication of gluten sensitivity in patients with primary Sjögren's syndrome (pSS). Material and methods. Rectal challenges with wheat gluten were performed in 20 patients with pSS and 18 healthy control subjects. Fifteen hours after challenge the mucosal production of nitric oxide (NO) was measured. Results. Five patients with pSS had a significant increase in the luminal release of NO after the rectal gluten challenge, indicating gluten sensitivity. All were HLA-DQ2 and/or -DQ8-positive. Two of the patients with increased NO had antibodies against transglutaminase and a duodenal biopsy showed an absolutely flat mucosa consistent with coeliac disease in one of the patients. Before gluten challenge, 15 of the Sjögren's syndrome (SS) patients reported gastrointestinal symptoms, and 8 reported intolerance to various food products. No correlation was found between gluten sensitivity and self-reported food intolerance or gastrointestinal symptoms. Conclusions. Rectal mucosal inflammatory response after gluten challenge is often seen in patients with pSS, signifying gluten sensitivity. However, this reactivity is not necessarily linked to coeliac disease.  相似文献   
4.
Parental longevity is associated with an increased life expectancy; results with regard to specific diseases are conflicting. There are limited data focusing on host characteristics and their effect on survival among multiple myeloma (MM) patients and individuals with monoclonal gammopathy of undetermined significance (MGUS). Therefore, our aim was to evaluate the impact of parental longevity on survival of patients with MM and MGUS. A total of 4675 patients with MM, 6812 MGUS patients and 13 398 population-based controls for MM as well as 19 110 controls for MGUS, from 1988 to 2013, were included in the study. Longevity was defined as >90 years of age. Among MM patients, parental longevity was associated with a decreased risk of death [hazard ratio (HR) = 0·92, 95% confidence interval (CI) 0·84–0·99] and the same was true for MGUS patients (HR = 0·87, 95% CI 0·78–0·96). Having one long lived parent significantly decreased the risk of death in both groups, but was not statistically significant when both parents exceeded 90 years of age. In conclusion, parental longevity decreases the risk of death for patients with MM and MGUS which may reflect the importance of the host's genetic and environmental factors in relation to survival.  相似文献   
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Purpose

The existing evidence suggests that a complete evaluation of mental health should incorporate both psychopathology and mental well-being indicators. However, few studies categorize European adolescents into subgroups based on such complete mental health data. This study used the data on mental well-being and symptoms of mental and behavioral disorders to explore the mental health profiles of adolescents in Europe.

Methods

Data collected from adolescents (N = 3767; mean age 12.4 [SD = 0.9]) from five European countries supplied the information on their mental well-being (personal resilience, school resilience, quality of life, and mental well-being) and mental and behavioral disorder symptoms (anxiety, depression, stress, bullying, cyber-bullying, and use of tobacco, alcohol, or cannabis). Multiple correspondence analysis and cluster analysis were combined to classify the youths into mental health profiles.

Results

Adolescents were categorized into three mental health profiles. The "poor mental health" profile (6%) was characterized by low levels of well-being and moderate symptoms of mental disorders. The "good mental health" profile group (26%) showed high well-being and few symptoms of mental disorders, and the "intermediate mental health" profile (68%) was characterized by average well-being and mild-to-moderate symptoms of mental disorders. Groups with higher levels of well-being and fewer symptoms of mental disorders showed lower rates of behavioral problems. Mental well-being indicators strongly contributed to this classification.

Conclusion

Adolescents with the "intermediate" or "poor" mental health profiles may benefit from interventions to improve mental health. Implications for school-based interventions are discussed.

Trial registration number (TRN) and date of registration

ClinicalTrials.gov Identifier: NCT03951376. Registered 15 May 2019.

  相似文献   
9.
Polymerase chain reaction for laboratory diagnosis of orf virus infections.   总被引:5,自引:0,他引:5  
BACKGROUND: The orf virus of sheep and goats is one of several zoonotic parapoxviruses. In the ovine/caprine host it causes contagious ecthyma (contagious pustular dermatitis, scabby mouth), but in humans it normally causes solitary or clustered orf lesions, typically on hands, arms or face. In addition to disease in the animals, the virus can be quite a nuisance as an occupational hazard in farmers and butchers. Clinical diagnosis is often possible, but laboratory diagnosis is sometimes necessary. For virus isolation, primary ovine or bovine cells, not routinely present, are needed. Serological methods exist, but electron microscopy is the most commonly used method. OBJECTIVES: To develop a reliable method for the laboratory diagnosis of orf zoonoses, without virus culture and without access to an electron microscope. STUDY DESIGN: A suitable primer pair was designed for orf polymerase chain reaction (PCR), using the Oligo software and sequence information from GenBank. Orf positive controls and specimens were kindly provided by several public health centers. Molluscum contagiosum specimens were provided by a dermatologist. HSV-1, HSV-2 and VZV positive swab specimens came from our routine diagnostic service. Asymptomatic skin specimens were obtained from sheep heads from the abattoir, and swab specimens from the heads of asymptomatic sheep. Selected amplified orf PCR positive specimens were sequenced to ensure the authenticity of the PCR products. Orf positive specimens were sent to another laboratory for electron microscopy. RESULTS AND CONCLUSIONS: A robust PCR was developed, with very small inter-run variation. All specificity demands were met, and the sensitivity seems to be good or excellent. All negative specificity controls from cell cultures and non-orf viruses were negative. Twenty-two (95.7%) of 23 scab or swab specimens with suspected orf etiology were orf PCR positive. Five of eight skin specimens from sheep heads from the abattoir were positive, and all 11 swab specimens from asymptomatic sheep were negative. Electron microscopy demonstrated orf-like particles in orf-PCR positive specimens. This PCR seems to be suitable as a diagnostic test for orf in humans, but asymptomatic virus shedding in sheep or goats may complicate veterinary applications of the assay.  相似文献   
10.
In spite of intense efforts no vaccine is yet available that protects against lentiviral infections. Sheep were immunised eight times over a period of 2.5 years with the maedi-visna (MVV) gag gene on two different vectors, 2 sheep with VR1012-gag-CTE and 2 sheep with pcDNA3.1-gag-CTE. All sheep responded to some of the mature MVV Gag proteins in Western blot (WB). Three of them responded to the virus in lymphocyte proliferation test. The sheep received a boost with recombinant Gag protein resulting in elevated antibody response. However, when they were challenged intratracheally with MVV they all became immediately infected as judged by a strong rise in antibody titer and virus isolation from blood. It is therefore clear that the vaccination gave no protection. It is even possible that it facilitated infectivity since virus was isolated earlier from all the vaccinated sheep than from any of the unvaccinated sheep infected in the same way with the same dose.  相似文献   
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