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A real-time PCR method was developed and used to detect Aspergillus fumigatus mitochondrial DNA (mtDNA) in bronchoalveolar lavage (BAL) fluids and tissue biopsy specimens. The analytical sensitivity of the assay was one A. fumigatus conidium per reaction, and the assay was linear at least over 4 orders of magnitude above the detection limit. BAL fluids from 66 immunocompromised patients at risk of invasive pulmonary aspergillosis (IPA) and 33 immunocompetent controls and tissue biopsy specimens from 10 immunocompromised patients were analyzed. The results were related to the clinical diagnosis established according to recently published consensus criteria. A. fumigatus mtDNA positivity was encountered in 16 of 81 (20%) BAL fluid specimens from patients at risk and 1 of 33 (3%) specimens from immunocompetent controls. PCRs were positive in six of seven, two of four, and four of five of the patients with proven, probable, and possible IPA, respectively, as well as in four patients at risk but without any other evidence of IPA. With qualitative detection, the diagnostic sensitivity of PCR was 73%, specificity was 93%, and predictive values of positive (PPV) and negative (NPV) results were 73 and 95%, respectively. Using a threshold cycle of <35 as a limit for positive PCR, the specificity and PPV of PCR in the diagnosis of invasive aspergillosis were 100%, but its sensitivity was only 45% and NPV was 92%. PCR was positive in tissue biopsy specimens from all patients with invasive aspergillosis caused by A. fumigatus. Semiquantitative detection of A. fumigatus mtDNA in BAL fluid may be helpful in the diagnosis of IPA. PCR is well suited for the verification of the presence of A. fumigatus in tissue biopsy specimens.  相似文献   
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We studied the salivary pH, buffer effect (BE), and flow rates of unstimulated and paraffin-stimulated saliva of 8 women in their late pregnancy and postpartum. Salivary samples were collected about 1 month prior to and about 2 months after delivery. In non-pregnant control women, two paraffin-stimulated salivary samples were collected 1 month apart. The salivary BE increased significantly from late pregnancy to postpartum without exception. The increase was 2.04±1.17 pH units (P < 0.001) on average. The BE increased from 4.79±1.64 (final pH) to 6.82±1.01 (final pH). This change was not due to variation in salivary flow rates, since both unstimulated and paraffin-stimulated flow rates remained unchanged. In control women the difference between the 2 BE measurements was only 0.13±0.47 pH units on average. We concluded that women with high postpartum BE values may have moderate or even low BE values in late pregnancy. In control women, individual variation was found to be low in all variables studied.

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International Journal of Paediatric Dentistry 2012; 22: 180–190 Objective. Xylitol studies suggest caries reductions in the order of 50%. Based on animal/microbial studies, erythritol potentially has caries‐preventive properties. However, clinical studies are required to confirm this.The aim of the study was to investigate the additional caries‐preventive effect of xylitol/maltitol and erythritol/maltitol lozenges delivered at school, relative to controls receiving comprehensive prevention, in a low‐caries prevalence population. Methods. A 4‐year, cluster‐randomized, double‐blinded clinical trial. Five hundred and seventy‐nine 10‐year‐old consenting subjects from 21 schools were randomly assigned to one of five groups. Four groups used the lozenges on school days, in three teacher‐supervised sessions daily, over 1 or 2 years. The daily amount was 4.7 g/4.6 g for xylitol/maltitol and 4.5 g/4.2 g for erythritol/maltitol. The groups received free examinations and care in the public health centre. Four hundred and ninety‐six children were analysed. The main outcome measure was dentin caries increment based on a clinical examination at 4 years since the start. The groups were compared in relation to the increment using hierarchical logistic regression to adjust for potential clustering. Results. Use of xylitol/maltitol or erythritol/maltitol lozenges did not result in caries reduction. A strong relationship between baseline caries prevalence and the 4‐year increment was observed (OR = 7.38; 95% CI: 3.78–14.41). Conclusions. The results suggest that in relatively low‐caries conditions the school‐based use of xylitol/maltitol or erythritol/maltitol lozenges would not have additional caries‐preventive effect when compared with comprehensive prevention.  相似文献   
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Objectives

The aim of this article is to describe the current status of geriatrics and position of geriatricians in 22 countries of three continents, and to portray their attitudes towards and resources allocated to geriatrics.

Methods

An electronic survey was delivered to a convenience sample of 22 geriatricians in leading positions of their countries.

Results

The time required in post graduation specialist training to become a geriatrician varied from one year (subspecialty in the USA) to six years (independent specialty in Belgium). The number in the population aged 80+ per geriatrician varied from 450 (Austria) to 25,000 (Turkey). Of respondents, 55% reported that geriatrics is not a popular specialty in their country. Acute geriatric wards, rehabilitation and outpatient clinics were the most common working places for geriatricians. Nearly half of the respondents had an opinion that older patients who were acutely ill, were receiving subacute rehabilitation or had dementia should be cared for by geriatricians whereas half of the respondents would place geriatricians also in charge of nursing home and orthogeriatric patients. The biggest problems affecting older people’s clinical care in their countries were: lack of geriatric knowledge, lack of geriatricians, and attitudes towards older people. Half of respondents thought that older people’s health promotion and comprehensive geriatric assessment were not well implemented in their countries, although a majority felt that they could promote good geriatric care in their present position as a geriatrician.

Conclusion

The position of geriatric, geriatricians’ training and contents of work has wide international variety.
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We have previously reported that, in young children, a risk-based caries prevention program compared with conventional prevention has a good caries-preventive effect. The present study aimed to assess the economic aspects of this program. We used the presence of mutans streptococci in plaque (Dentocult-SM) and/or the presence of incipient carious lesions at 2 years of age for risk assessment, and measured the outcome of caries (yes/no) at the age of 5 years. Dental assistants carried out the screening and preventive work. The economic analysis included the actual running costs of the program during the 3-year follow-up based on the time spent on dental visits. The costs per child per 3 years were significantly lower in the risk-based group (54 euros) than in the conventional prevention group (69 euros) (Student's t test, P = 0.004). If a dentist with an assistant had done all the work, the costs would have been twice as high. Compared to conventional prevention, the results suggest that risk-based prevention can be effective in reducing both costs and dental caries in preschool children, provided that the screening and preventive measures are delegated to preventive dental assistants.  相似文献   
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Our aim was to study the effects of mildly flavoured sodium lauryl sulphate (SLS)-containing and detergent-free toothpastes with and without betaine (BET) on subjective symptoms of dry mouth in a randomised clinical trial. BET is an osmoprotectant that reacts with molecules to supply the surface with a water coating that protects cells from surfactants. Twenty-seven xerostomic patients and 18 healthy controls took part in the randomised, double-blind clinical trial with a crossover design. Three mildly flavoured toothpastes: (1) 4% BET, (2) 1% SLS and 4% BET, and (3) 1% SLS were used for six weeks each. The reference or washout paste contained neither SLS nor BET. The subjects' dental appointments were at the beginning of the trial and before and after the use of each toothpaste. At each appointment, the subjects were interviewed about subjective sensations of dry mouth (Visual Assessment Scoring (VAS) Index). The subjects did not report any adverse effects in connection with the use of the toothpastes. The VAS scores for lip dryness and eating difficulties were significantly lower for the BET paste (lip dryness: BET相似文献   
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