运用高时空分辨率MR k空间及时间敏感编码技术实时评估先天性心脏病病人左、右心室容积及功能

目的比较心电门控MR电影成像、标准实时MR成像及实时k空间-时间敏感编码成像3种技术评估先天性心脏病病人心室容积的大小。材料与方法本研究经学术伦     

腰椎间盘碎片在前硬膜囊外间隙中游走路径的MRI观察

目的 观察前硬膜囊外间隙(AES)椎间盘碎片的游走路径。方法 搜集经手术证实的18例腰椎间盘髓核脱出(HNP)，进行MRI回顾分析。结果 在椎管内，当碎片从供体间盘脱出游走时，向上12例，向下6例。10例占据右隔区，8例占据左隔区。碎片经常被限制在AES左半区和右半区，很少位于中线。在矢状面，T2wI显示碎片为低或等信号压迫硬膜囊，T1WI显示碎片为等信号并压迫后纵韧带(PLL)、脊髓。在轴面，T2WI显示碎片压迫中线隔、后纵韧带、硬膜囊。脂肪抑制扫描显示碎片信号增高。结论 间盘碎片游走路径由AES的解剖决定。抑脂扫描有临床诊断意义。     

Automatic volumetric capillary cytometry for counting white cells in white cell-reduced plateletpheresis components

BACKGROUND: As the benefits of white cell (WBC)-reduced blood components become increasingly apparent, the need has arisen for a simple, automated WBC-counting technique that is sensitive to low WBC concentrations. Automated volumetric capillary cytometry was evaluated for its ability to quantify residual WBCs in WBC-reduced plateletpheresis components. STUDY DESIGN AND METHODS: The volumetric capillary cytometry system evaluated uses a laser to excite fluorescent dye-labeled nucleated cells. The number of nucleated cells per microliter is reported. Four studies were performed: linearity, precision of results near the value of 5 × 10(6) WBCs per unit, the limit of detection, and correlation to the Nageotte manual counting method. RESULTS: Assay values correlated to expected values (range, 0- 125 WBC/microliter) with an r2 > 0.99. In the range of 5 × 10(5) WBCs per unit the CV was 8.5 percent, and concentration differences of 0.15 log10 were detectable. The limit of detection was 1.0 WBCs per microliter (95% upper confidence limit). The assay correlated to the Nageotte method with an r2 of 0.98, slope of 1.0, and y-intercept of 2.0 WBCs per microliter. Assay results were 10 to 15 percent higher than Nageotte results, in samples with values near 5 × 10(6) WBCs per unit. Technician time per sample was 2 to 3 minutes. CONCLUSION: Volumetric capillary cytometry is precise and sensitive to small differences in WBC concentration in the range of clinical interest. The device provides an efficient new method for quality assurance and control of WBC-reduced plateletpheresis products.     

Specific proliferative T cell responses and antibodies elicited by vaccination with simian immunodeficiency virus Nef do not confer protection against virus challenge.

The efficacy of immunizing with a combination of simian immunodeficiency virus (SIV) Nef vaccines was evaluated. Four vaccinates received three intradermal immunizations with recombinant vaccinia virus that expressed SIV Nef, followed by three intramuscular immunizations with rDNA also expressing SIV Nef. Finally, the four vaccinates received two subcutaneous boosts with recombinant SIV Nef protein. This immunization protocol elicited anti-Nef antibodies in all of the vaccinates as well as specific proliferative responses. However, specific cytotoxic T cell responses were not detected before virus challenge. All vaccinates were challenged intravenously with 10 MID(50) of SIVmacJ5 along with four controls. All eight subjects became infected after SIV challenge and there were no group-specific differences in virus load as measured by virus titration and vRNA analysis. The results of this study support indirectly the report from Gallimore and colleagues (Nat Med 1995;1:1667) suggesting that CD8(+) T lymphocyte responses are required for Nef-based vaccines to restrict SIV infection. If Nef-based vaccines are to be beneficial in controlling infection with immunodeficiency viruses, then it will be necessary to develop more effective immunization protocols that elicit potent CD8(+) cell responses reproducibly.     

Health effects of exposure to cyanobacteria (blue–green algae) during recreational water–related activities

Abstract: The aim of this study was to investigate effects on health of exposure to cyanobacteria as a result of recreational water activities. Participants, who were aged six years and over, were interviewed at water recreation sites in South Australia, New South Wales and Victoria on selected Sundays during January and February 1995. Telephone follow–up was conducted two and seven days later to record any subsequent diarrhoea, vomiting, flu–like symptoms, skin rashes, mouth ulcers, fevers and eye or ear irritations. On the Sundays of interview, water samples from the sites were collected for cyanobac–terial cell counts and toxin analysis. There were 852 participants, of whom 75 did not have water contact on the day of interview and were considered unexposed. The 777 who had water contact were considered exposed. No significant differences in overall symptoms were found between the unexposed and exposed after two days. At seven days, there was a significant trend to increasing symptom occurrence with duration of exposure (P = 0.03). There was a significant trend to increasing symptom occurrence with increase in cell count (P = 0.04). Participants exposed to more than 5000 cells per mL for more than one hour had a significantly higher symptom occurrence rate than the unexposed. Symptoms were not correlated with the presence of hepatotoxins. These results suggest symptom occurrence was associated with duration of contact with water containing cyanobacteria, and with cyanobacterial cell density. The findings suggest that the current safety threshold for exposure of 20 000 cells per mL may be too high. (Aust N Z J Public Health 1997; 21: 562–6)     

Trends in inhalation exposure--a review of the data in the published scientific literature

As part of a larger study aimed at identifying the long-term changes in inhalation exposure for selected hazardous substances in a number of industrial sectors within the UK, we have reviewed the published literature on temporal changes in inhalation exposure. Scientific papers and reports of interest were identified using standard literature review techniques. Most studies did not express the results as relative annual trends in exposure, and so where possible the data were reanalysed using regression methods to produce estimates of the average annual percentage change in concentration. In the majority of instances, there were significant reductions in exposure, with percentage yearly declines up to 32%. In many studies, information about changes in the working environment, process conditions or other factors that may have influenced the change in exposure over time was lacking. Factors commonly cited as being responsible for exposure reductions included the introduction of new standards and response to regulatory requirements as well as changes in production methods. A large number of exposure measurement datasets exist for many industrial sectors for most of the second half of the 20th century and this resource has allowed us to identify trends in occupational exposure. It is most important that longitudinal exposure data continue to be collected along with relevant contextual information to enable future changes to be adequately assessed.     

Evaluation of the European Heart Failure Self-care Behaviour Scale in a United Kingdom population

AIM: This paper is a report of a study to test the internal consistency, reliability and validity of the 12-item European Heart Failure Self-care Behaviour Scale in an English-speaking sample in the United Kingdom. BACKGROUND: The European Heart Failure Self-care Behaviour Scale quantifies the measures patients take to manage their heart failure. Produced in the Netherlands and Sweden, it has been translated into English. METHODS: A convenience sample of 183 patients (response rate 85%) with heart failure (New York Heart Association, Class I-IV) was recruited from an outpatient clinic between July 2004 and July 2005. Mainly men (n = 143), they had a mean age of 65.6 years (sd = 12.3). They completed the Minnesota Living with Heart Failure Questionnaire, the Self-Care of Heart Failure Index, and the European Heart Failure Self-care Behaviour Scale during their clinic visit. The latter questionnaire was repeated at home within 2 weeks. RESULTS: The scale was reliable but internal consistency was only moderate (Cronbach's alpha = 0.69) and lower than in other European populations. It appears to be repeatable in the short-term. Comparison with the Self-Care of Heart Failure Index raised questions about whether the two questionnaires measured the same concept. Variance in self-care was not explained by gender, age or severity of heart failure. CONCLUSION: As self-care is an important component in the life of patients with heart failure, further exploration of the methods for measuring patients' self-care behaviours is warranted to enable healthcare staff to assess patients effectively. This would also help in understanding the applicability of tools in a range of patients, cultures and settings.     

Cultural and linguistic diversity of people living with chronic hepatitis B in 2011–2016: changing migration,shifting epidemiology

Objective : To estimate the cultural and linguistic diversity in Australians currently living with chronic hepatitis B (CHB), the majority of whom were born overseas, and to identify trends in this diversity over time. Methods : Estimates were generated by combining Australian census country of birth information with seroprevalence data generated from antenatal serology linked with surveillance notifications. The number of people living with CHB was assessed according to country of birth using the 2011 and 2016 censuses. Results : The total number of Australian residents living with CHB increased by 20% between 2011 and 2016, substantially outpacing population growth. The most common country of birth continued to be China, with the number of Chinese‐born Australians living with CHB increasing by 60% in the 5‐year period. Decreased numbers were observed for people born in European countries. Conclusions : The epidemiology of chronic hepatitis B in Australia has shifted over time due to changing migration patterns, with increases in many countries in the Asia‐Pacific, African and Middle Eastern regions. Implications for public health : Interventions to improve the health of people living with CHB are imperative, and these up‐to‐date estimates identify priority groups and communities, which are constantly changing.     

Regenerative medicine: Stroke survivor and carer views and motivations towards a proposed stem cell clinical trial using placebo neurosurgery

Background

Few studies explore stroke survivor views and motivations towards stem cell therapy (SCT). This qualitative study explores the views and motivations of both stroke survivors and their partners/carers towards a proposed 2‐arm Phase III Randomised Controlled Trial (RCT) comparing intracerebral insertion of stem cells with placebo neurosurgery in stroke survivors with disability.

Objective

To explore views and motivations towards a proposed 2‐arm stem cell trial and identify factors that may impede and enhance participation.

Design

This study adopts a naturalistic design to explore the complexity of this field, employing a participatory action‐research approach comprising a specialized Conversation (World) Café form of focus group. Data were collected via 5 Conversation Cafés with stroke survivors (age 40‐75) and partners/carers between June and October 2016. Of 66 participants, 53 (31 male, 22 female) were stroke survivors and 13 (6 female, 7 male) were partners/carers. Qualitative data were analysed using a thematic approach.

Discussion and Conclusion

Stroke survivor views and motivations reflect anticipation of the personal and future benefits of regenerative medicine. Partners/carers sought to balance the value of stroke survivor hope with carrying the weight of hope as carer, a conflict burden adding to known caregiver burden. All participants expressed the need for during and post‐trial psychological support. This study provides a rare opportunity to explore the prospective views and motivations of stroke survivors and their partners/carers towards a proposed Phase III 2‐arm RCT. This adds weight to qualitative evidence exploring capacity, consent, decision making, perceptions of treatment risk and supports required for clinical trial participation.     

Studies of antibodies in the sera of patients who have made red cell autoantibodies

BACKGROUND: In patients in whom autoantibodies of broad specificity (panagglutinins) are present in the serum, adsorption studies are often necessary to identify alloantibodies that are simultaneously present. STUDY DESIGN AND METHODS: Samples from 138 patients in whom the direct antiglobulin test was positive and antibody was present in the serum were studied. When antibody identification studies before or after initial adsorption suggested the presence of an alloantibody, additional alloadsorptions were performed. RESULTS: Among the samples from 138 patients, 71 contained only panagglutinating autoantibody, and another 19 contained either autoantibodies or alloantibodies that were not accompanied by panagglutinins. The remaining 48 samples contained both panagglutinins and a total of 62 antibodies that appeared to be alloimmune in nature. Alloadsorption with antigen-negative red cells showed that 29 (47%) of the apparent alloantibodies were in fact partially adsorbed autoantibodies that mimicked alloantibodies by their reactions. CONCLUSION: Initial autoadsorption often left unadsorbed alloantibodies and autoantibodies with mimicking specificities. Initial alloadsorption more often left only true alloantibodies unadsorbed. From the screening tests, it appeared that 43 percent of the 138 patients were alloimmunized. Recognition of the mimicking nature of the partially adsorbed autoantibodies found that the real incidence of alloimmunization in the patients was 23 percent. Recognition of this phenomenon considerably simplifies the selection of blood for transfusion to these patients.