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131.
Fusion proteins present in leukemic cells frequently contain a new amino acid at the fusion point. We tested whether a peptide (BCR1/25) encompassing the fusion region of the hybrid molecule pml/RAR alpha, which is selectively expressed by acute promyelocytic leukemia (APL) cells, can be recognized by human T lymphocytes in vitro. CD4+ lymphocytes, at both polyclonal and clonal level, recognized peptide BCR1/25 in an HLA-DR--restricted fashion on presentation by autologous antigen-presenting cell (APC) or by APC expressing the HLA-DR11 restricting molecule. Control peptides corresponding to the normal pml and RAR alpha proteins were not recognized. One clone (DEG5) also exerted a high and specific cytotoxicity against autologous cells pulsed with BCR1/25. The autologous DE LCL containing a transduced pml/RAR alpha fusion gene and expressing a bcr1 type of the pml/RAR alpha hybrid protein induced the proliferation of DE anti-BCR1/25 T cell clones. It is concluded that the bcr1 type-pml/RAR alpha fusion protein of APL contains an antigenic site, absent from the normal parent molecules and recognized by human CD4+ lymphocytes.  相似文献   
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There is little information available concerning whether, and to what extent, migraine-prophylactic agents interfere with the symptoms of migraine attacks. The present study is a placebo-controlled, double-blind study concerning metoprolol in classic migraine. The data refer to the symptoms of single migraine attacks. During metoprolol treatment more attacks were characterized as mild (p = 0.002), and mean global rating (an integrated estimate of headache intensity and of other discomfort) was lower (4.2 versus 5.2, p = 0.003). The mean headache intensity per attack (1.97 versus 2.15) and the mean duration (5.5 versus 6.8 h) were not significantly different. Consumption of analgesics per attack was lower during metoprolol treatment (0.6 versus 1.1; p = 0.02). Attacks with associated symptoms accompanying the headache were fewer during metoprolol treatment (p = 0.014). Total visual and non-visual aura symptoms occurred with similar frequency, but scintillations and paraesthesia were more frequent during metoprolol treatment, whereas speech disturbances were less frequent. In spite of lower consumption of analgesics, the symptoms appeared milder during metoprolol than during placebo. The pattern of changes indicates that metoprolol exerts its action via the sympathetic nervous system; peripheral vasoconstriction is hardly the underlying mechanism of action.  相似文献   
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Metal implants are commonly used in orthopedic surgery. The mechanical stability and longevity of implants depend on adequate bone deposition along the implant surface. The cellular and molecular mechanisms underlying peri-implant bone formation (ie, osseointegration) are incompletely understood. Herein, our goal was to determine the specific bone marrow stromal cell populations that contribute to bone formation around metal implants. To do this, we utilized a mouse tibial implant model that is clinically representative of human joint replacement procedures. Using a lineage-tracing approach, we found that both Acta2.creERT2 and Tmem100.creERT2 lineage cells are involved in peri-implant bone formation, and Pdgfra- and Ly6a/Sca1-expressing stromal cells (PαS cells) are highly enriched in both lineages. Single-cell RNA-seq analysis indicated that PαS cells are quiescent in uninjured bone tissue; however, they express markers of proliferation and osteogenic differentiation shortly after implantation surgery. Our findings indicate that PαS cells are mobilized to repair bone tissue and participate in implant osseointegration after surgery. Biologic therapies targeting PαS cells might improve osseointegration in patients undergoing orthopedic procedures. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Australia has a universal infant pneumococcal conjugate vaccination program and until recently a universal pneumococcal polysaccharide vaccine program for non-Indigenous adults aged ≥65 years and Indigenous adults aged ≥50 years. We documented the impacts of infant and adult vaccination programs on the epidemiology of invasive pneumococcal disease (IPD) in Indigenous and non-Indigenous adults.IPD notifications from the National Notifiable Disease Surveillance System were analysed from 2002 to 2017, grouped by age, vaccine serotype group and Indigenous status. Since the universal funding of infant and elderly pneumococcal vaccination programs in January 2005, total IPD decreased by 19% in non-Indigenous adults aged ≥65 years but doubled in Indigenous adults aged ≥50 years. Vaccine uptake was suboptimal in both groups but lower in Indigenous adults. IPD due to the serotypes contained in the pneumococcal conjugate vaccines (PCV) except for serotype 3 declined markedly over the study period but were replaced by non-PCV serotypes. Serotype 3 is currently the most common in older adults. In the populations eligible for the adult 23-valent pneumococcal polysaccharide vaccine (23vPPV) program, IPD rates due to its exclusive serotypes increased to a lower extent than non-vaccine types. In 2017, non-vaccine serotypes accounted for most IPD in the older population eligible for the 23vPPV program, while it's eleven exclusive serotypes accounted for the majority of IPD in younger adults.Infant and adult pneumococcal vaccination programs in Australia have shaped the serotype-specific epidemiology of IPD in older adults. IPD remains a significant health burden for the Indigenous population. Herd immunity impact is clear for PCV serotypes excluding serotype 3 and serotype replacement is evident for non-PCV serotypes. The adult 23vPPV immunisation program appears to have partially curbed replacement with IPD due to its eleven exclusive serotypes, highlighting a potential benefit of increasing adult 23vPPV coverage in Australia.  相似文献   
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Abstract: Background: Severe nausea and vomiting in pregnancy (hyperemesis gravidarum) can be a distressing and debilitating condition when it is uncontrolled. For all concerned, hyperemesis gravidarum can be difficult to treat satisfactorily, and women tend to be admitted to a hospital several times during early pregnancy. Our research objectives were to describe the experience of hyperemesis gravidarum from the perspective of affected women and to explore with health care professionals the barriers and facilitators to caring for women with the condition. Methods: A qualitative research design was used. A total of 18 women were interviewed, of whom 8 had two or more interviews. Seven focus groups were conducted with health care professionals. Thematic data analysis was undertaken. Results: The main themes emerging from the women’s data were the effect and burden of the symptoms of the condition and feeling unpopular with staff. From the practitioner data, the main themes were the validity (or invalidity) of hospitalization for women, skepticism of the severity of symptoms, the psychological and social dimensions of the condition, and inadequate primary care services. Conclusions: The main findings revealed that hyperemesis gravidarum is a debilitating condition and that the unhelpful attitudes of practitioners may affect whether women access timely and appropriate care. Many women appear to be unsupported by primary care services and are distressed when perceived either as “time wasters” or someone else’s responsibility. We propose that a tailored assessment and care plan for each woman is needed to help them control their symptoms, which ideally should be delivered in the community. (BIRTH 37:3 September 2010)  相似文献   
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