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In medical research, repeated questionnaire data is often used to measure and model latent variables across time. Through a novel imputation method, a direct comparison is made between latent growth analysis under classical test theory and item response theory, while also including effects of missing item responses. For classical test theory and item response theory, by means of a simulation study the effects of item missingness on latent growth parameter estimates are examined given longitudinal item response data. Several missing data mechanisms and conditions are evaluated in the simulation study. The additional effects of missingness on differences in classical test theory- and item response theory-based latent growth analysis are directly assessed by rescaling the multiple imputations. The multiple imputation method is used to generate latent variable and item scores from the posterior predictive distributions to account for missing item responses in observed multilevel binary response data. It is shown that a multivariate probit model, as a novel imputation model, improves the latent growth analysis, when dealing with missing at random (MAR) in classical test theory. The study also shows that the parameter estimates for the latent growth model using item response theory show less bias and have smaller MSE's compared to the estimates using classical test theory. [ABSTRACT FROM AUTHOR]

Latent growth models are often used to measure individual trajectories representing change over time. The characteristics of the individual trajectories depend on the variability in the longitudinal outcomes. In many medical and epidemiological studies, the individual health outcomes cannot be observed directly and are indirectly observed through indicators (i.e. items of a questionnaire). An item response theory or a classical test theory measurement model is required, but the choice can influence the latent growth estimates. In this study, under various conditions, this influence is directly assessed by estimating latent growth parameters on a common scale for item response theory and classical test theory using a novel plausible value method in combination with Markov chain Monte Carlo. The latent outcomes are considered missing data and plausible values are generated from the corresponding posterior distribution, separately for item response theory and classical test theory. These plausible values are linearly transformed to a common scale. A Markov chain Monte Carlo method was developed to simultaneously estimate the latent growth and measurement model parameters using this plausible value technique. It is shown that estimated individual trajectories using item response theory, compared to classical test theory to measure outcomes, provide a more detailed description of individual change over time, since item response patterns (item response theory) are more informative about the health measurements than sum scores (classical test theory). [ABSTRACT FROM AUTHOR]

Aims: Amyotrophic lateral sclerosis (ALS) is a chronic neurodegenerative disease characterized by progressive loss of motor neurons, muscle weakness, spasticity, paralysis and death usually within 2–5 years of onset. Neuroinflammation is a hallmark of ALS pathology characterized by activation of glial cells, which respond by upregulating small heat shock proteins (HSPBs), but the exact underlying pathological mechanisms are still largely unknown. Here, we investigated the association between ALS disease duration, lower motor neuron loss, TARDNA‐binding protein 43 (TDP‐43) pathology, neuroinflammation and HSPB expression. Methods: With immunohistochemistry, we examined HSPB1, HSPB5, HSPB6, HSPB8 and HSP16.2 expression in cervical, thoracic and sacral spinal cord regions in 12 ALS cases, seven with short disease duration (SDD), five with moderate disease duration (MDD), and ten age‐matched controls. Expression was quantified using ImageJ to examine HSP expression, motor neuron numbers, microglial and astrocyte density and phosphorylated TDP‐43 (pTDP‐43+) inclusions. Results: SDD was associated with elevated HSPB5 and 8 expression in lateral tract astrocytes, while HSP16.2 expression was increased in astrocytes in MDD cases. SDD cases had higher numbers of motor neurons and microglial activation than MDD cases, but similar levels of motor neurons with pTDP‐43+ inclusions. Conclusions: Increased expression of several HSPBs in lateral column astrocytes suggests that astrocytes play a role in the pathogenesis of ALS. SDD is associated with increased microgliosis, HSPB5 and 8 expression in astrocytes, and only minor changes in motor neuron loss. This suggests that the interaction between motor neurons, microglia and astrocytes determines neuronal fate and functional decline in ALS. [ABSTRACT FROM AUTHOR]

Summary: Multiple sclerosis (MS) is a chronic neurodegenerative disease characterized by demyelination, inflammation and neurodegeneration throughout the central nervous system. Although spinal cord pathology is an important factor contributing to disease progression, few studies have examined MS lesions in the spinal cord and how they differ from brain lesions. In this study we have compared brain and spinal cord white (WM) and grey (GM) matter from MS and control tissues, focusing on small heat shock proteins (HSPB) and HSP16.2. Western blotting was used to examine protein levels of HSPB1, HSPB5, HSPB6, HSPB8 and HSP16.2 in brain and spinal cord from MS and age‐matched non‐neurological controls. Immunohistochemistry was used to examine expression of the HSPs in MS spinal cord lesions and controls. Expression levels were quantified using ImageJ. Western blotting revealed significantly higher levels of HSPB1, HSPB6 and HSPB8 in MS and control spinal cord compared to brain tissues. No differences in HSPB5 and HSP16.2 protein levels were observed, although HSPB5 protein levels were higher in brain WM versus GM. In MS spinal cord lesions, increased HSPB1 and HSPB5 expression was observed in astrocytes, and increased neuronal expression of HSP16.2 was observed in normal‐appearing GM and type 1 GM lesions. The high constitutive expression of several HSPBs in spinal cord and increased expression of HSPBs and HSP16.2 in MS illustrate differences between brain and spinal cord in health and upon demyelination. Regional differences in HSP expression may reflect differences in astrocyte cytoskeleton composition and influence inflammation, possibly affecting the effectiveness of pharmacological agents. Multiple sclerosis is a chronic inflammatory disease affecting the whole of the CNS yet very few studies detail the pathology of the spinal cord. Here we show regional differences in HSP expression with higher constitutive expression of HSP in the spinal cord. This may reflect differences in astrocyte cytoskeleton composition, influence the degree of inflammation and thus damage. Such pathological differences are key to understanding diseases processes that may affect local effectiveness of pharmacological agents. [ABSTRACT FROM AUTHOR]

Background and objectives: New technologies continue to be developed in clinical dentistry, but not all are adopted for use. This study aimed to update information on the use of newer technologies among New Zealand dentists and to evaluate the factors that influenced their adoption. Methods: Electronic and postal questionnaires were sent to a random sample of 573 dentists, consisting of general dental practitioners (GDPs) and dental specialists enrolled on the Dental Council of New Zealand Dentists' Register. Results: Responses were received from 232 dentists (40.5%). Of the 17 technologies investigated, digital intraoral radiography (88.7%), digital apex locators (77.4%) and rotary endodontic units (74.5%) were the most commonly used. Least commonly-used were digital impressions (4.7%), digital colour determination (2.8%) and ozone units (1.4%). Dentists used an average of 4.9 ± 2.5 technologies. The use of technologies showed few significant differences by dentists' personal or practice characteristics apart from a higher average among men than women (p < 0.01). Improving quality of care and improving efficiency were ranked as the two most important factors when deciding about using newer technologies. Since a 2007 New Zealand study, the use of digital radiography and dental laser units has increased, whereas the use of power bleaching, caries diagnosis and ozone units has decreased. The use of other technologies has remained similar. Conclusions: Insight into the changing trends in the adoption of dental technologies heightens practitioners' and educators' understanding of what works for dentists, besides helping to shape future directions in technological developments in dentistry. [ABSTRACT FROM AUTHOR]

Aims: Cell matrix modulating protein SPARCL-1 is highly expressed by astrocytes during CNS development and following acute CNS damage. Applying NanoLC-MS/MS to CSF of RRMS and SPMS patients, we identified SPARCL-1 as differentially expressed between these two stages of MS, suggesting a potential as CSF biomarker to differentiate RRMS from SPMS and a role in MS pathogenesis. Methods: This study examines the potential of SPARCL-1 as CSF biomarker discriminating RRMS from SPMS in three independent cohorts (n = 249), analyses its expression pattern in MS lesions (n = 26), and studies its regulation in cultured human brain microvasculature endothelial cells (BEC) after exposure to MS-relevant inflammatory mediators. Results: SPARCL-1 expression in CSF was significantly higher in SPMS compared to RRMS in a Dutch cohort of 76 patients. This finding was not replicated in 2 additional cohorts of MS patients from Sweden (n = 81) and Switzerland (n = 92). In chronic MS lesions, but not active lesions or NAWM, a vessel expression pattern of SPARCL-1 was observed in addition to the expression by astrocytes. EC were found to express SPARCL-1 in chronic MS lesions, and SPARCL-1 expression was regulated by MS-relevant inflammatory mediators in cultured human BEC. Conclusions: Conflicting results of SPARCL-10s differential expression in CSF of three independent cohorts of RRMS and SPMS patients precludes its use as biomarker for disease progression. The expression of SPARCL-1 by BEC in chronic MS lesions together with its regulation by inflammatory mediators in vitro suggest a role for SPARCL-1 in MS neuropathology, possibly at the brain vascular level. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence and risk factors for human immunodeficiency virus (HIV) and tuberculosis (TB) infection and investigate the relationship between these two infections in homeless adults.Design: Cross-sectional study.Setting: Inner-city shelters and free meal programs.Participants: A representative sample of 1226 adults (> or = 18 years) were enrolled from community sites.Main Outcome Measures: Serum HIV-1 antibody status and tuberculin skin test reactivity.Results: Human immunodeficiency virus seroprevalence was 8.5% (95% confidence interval [CI], 7.0% to 10.1%) and the prevalence of TB infection was 32% (95% CI, 30% to 37%). Nineteen percent of the HIV-seropositive subjects had positive tuberculin skin tests. Independent risk factors for HIV infection included younger age, black race, male homosexual contact, injection drug use, use of injection drugs in shooting galleries, and selling sex. Tuberculosis infection was associated with the duration of homelessness and living in crowded shelters or single-room-occupancy hotels. Injection drug use, a risk factor for HIV, was also a risk factor for TB, with a particularly strong association in women. No evidence of an association between TB and HIV infection was found, even after accounting for anergy.Conclusions: The homeless population in the United States should be considered a group at high risk for HIV infection and TB. Given the constellation of risk factors present, the high prevalence of infection, and lack of access to medical services, we anticipate that these communicable diseases in this population will represent a growing public health problem. [ABSTRACT FROM AUTHOR]

Therefore, this study aims to evaluate the prenatal course, prenatal diagnostic classification accuracy and postnatal outcomes of fetuses suspected of a CLA. During prenatal follow-up four fetus developed hydrops, of which only one case resulted in term birth. Congenital lung anomalies (CLA) are malformations of the lower respiratory tract which are commonly detected on ultrasound examination during the second trimester. [Extracted from the article]

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Aim To examine the influence of dental students' gender and ethnicity on their perceptions of dental nurses' duties and upon their communication and working styles when interacting with dental nurses (DNs).Method A survey of clinical dental students attending Queen's University Belfast and University of Leeds. Students were invited to complete the 34 item Communication and Working Styles Questionnaire. The questionnaire assessed the students' perceptions of the duties of a DN and the students' communication and working styles. Factor analysis revealed two communication and working styles which were friendly and difficult styles, respectively.Results Two hundred and forty-eight students participated giving a response rate of 88%: 58% were female and 30% of students from Leeds were from various ethnic minority groups. The students' perceptions as to the duties of a DN were affected by university attended and ethnicity. The majority of students used friendly communication styles. The type of style used was determined by university attended, gender and ethnicity. Male students had higher mean scores for friendly working styles whereas students from minority ethnic groups had higher mean scores for gender-related communication style. Female students and students from minority ethnic groups had higher mean scores for items relating to teamwork.Conclusions This survey illustrates the different communication and working styles used by male and female and dental students from different ethnic backgrounds when interacting and working with DNs. [ABSTRACT FROM AUTHOR]

Objectives To investigate if dental nurses perceive gender differences in the communication and interaction style used by their dentist in general practice.Methods Data were collected from 64 Northern Irish dental nurses (70% response), and from 549 Dutch nurses (41% response). Respondents completed the Communication and Working Styles Questionnaire (CWSQ), a self-report questionnaire with 20 items on staff communication and working styles. Using principal component analysis, six distinguishable factors could be extracted: [1] gender-related (four items, Cronbach's α = 0.78), [2] friendly relation (four items, α = 0.66), [3] teamwork (four items, α = 0.44), [4] playfulness (two items, α = 0.69), [5] personal attention (three items, α = 0.60), and [6] business-like (two items, α = 0.32). Factors [3] and [6] were additionally analysed at item level given their low internal consistencies.Results MANOVA indicated a main effect for dentist's gender [F(6,541) = 4.649, p < 0.001], and for country [F(6,541) = 37.601, p < 0.001] on the communication style scales. No interaction effect of gender with country was found. Nurses working with a male dentist had higher scores for the 'gender-related' communications styles, whereas those working with a female dentist had higher scores for 'friendly-relation' and 'personal attention' communication styles. Dutch nurses had higher scores on 'playfulness', whereas Northern Irish nurses had higher scores on 'friendly relation' and 'personal attention' communication styles. Some additional differences were found at item level. The age of the dental nurse explained some differences in communication and working styles [F(6,541) = 2.341, p = 0.031); younger dental nurses scored significantly higher for 'gender- related' communication and working style.Conclusion Gender of the dentist does influence dental nurses' perceptions of the communication styles used in the primary dental care setting. Dental nurses working with female dentists report a style predominantly characterised by 'friendly-relation' and 'personal attention', whereas those working with a male dentist report 'gender-related' communication and working styles. Given the steadily growing percentage of females entering the dental profession, it is recommended to raise both dentists' and nurses' awareness on gender influences in professional communication by introducing these topics in their respective education. [ABSTRACT FROM AUTHOR]

Objectives To investigate if women compared with men dentists experience deferential treatment from their female nurses, what workplace strategies women use to manage chair-side assistance and to examine if these were country related.Method A convenience sample of 22 male and female dentists of different ages working in general dental practice in The Netherlands and Northern Ireland participated. The sample framework was determined by saturation of the concepts. All informants were interviewed in a clinical setting. The data was subjected to rigorous line by line coding in order to identify clusters of codes, themes and concepts.Results Three themes were identified. These were: experiencing deferential nursing assistance; adopting 'friendly-like' working strategies and adopting business-like, hierarchical working strategies. Gender differences were shown for each of the themes. Women rather than men made friends with their nurses and attempted to reduce status inequalities. This led to workplace strategy inconsistencies. This suggested that it was not the type of strategy adopted but the inconsistency with which it was implemented that caused difficulties between younger women dentists and their nurses.Conclusions Training dental students and young graduates how to interact appropriately in the clinical situation and to appreciate the nurses' work status will assist in improving working relationships. [ABSTRACT FROM AUTHOR]

We randomized 389 symptomatic patients with human immunodeficiency virus (HIV) infection to ditiocarb sodium (400 mg/m2 orally for 24 weeks) or a placebo. Patients were well balanced according to Centers for Disease Control (CDC) group, CD4+ cell number, and duration of disease prior to entry. Ten new acquired immunodeficiency syndrome (AIDS)-defining opportunistic infections occurred in the treated patients and 21 in the controls. Reduction of new opportunistic infections in the ditiocarb group was significant in all patients (relative risk [RR], 0.44) and in patients with AIDS (CDC groups IV-C1 and IV-D) (RR, 0.12). The size of the effect of ditiocarb was maintained when data were reanalyzed after exclusion of a patient who progressed to Pneumocystis carinii pneumonia who was not strictly CDC-defined (RR, 0.46), or when considering as new opportunistic infections three events, which were clinically active at entry, but for which the definitive diagnosis was made during study (RR, 0.49). The administration of ditiocarb did not induce any major adverse clinical or biological reactions. We conclude that, in this study, ditiocarb was safe and reduced the incidence of opportunistic infections in patients with symptomatic HIV infection. [ABSTRACT FROM AUTHOR]

Study Objective: To evaluate the tolerance and safety of oral dextran sulfate (UA001), a potent in-vitro inhibitor of human immunodeficiency virus (HIV) in patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related complex.Design: Unblinded, dose-escalation 8-week trial.Setting: An AIDS outpatient clinic of a university-affiliated municipal hospital.Patients: Thirty-four patients with stage III or IV HIV infection were enrolled. Five patients in six different dosage cohorts completed the study. The population was predominantly homosexual men with persistent generalized lymphadenopathy (stage III).Interventions: Oral dextran sulfate was given three times daily in total daily doses of 900 to 5400 mg for 8 weeks. Patients were monitored for tolerance and toxicity. Immunologic and virologic values were also followed.Measurements and Main Results: Oral dextran sulfate was given without significant side effects. The commonest minor subjective complications were mental hyperexcitability and gastrointestinal complaints. The most frequent laboratory abnormalities were leukopenia and hepatic transaminase elevations. Eleven patients required dose reductions, and therapy was stopped in 4 because of toxicities. The CD4 lymphocyte numbers did not change appreciably. No decline in beta-2 microglobulin levels occurred. The HIV antigen levels were unchanged from baseline. No assay for dextran sulfate plasma levels has yet proven successful.Conclusions: Oral dextran sulfate appears to be well tolerated. No evidence of systemic absorption of the parent compound is available. However, in view of the promising in vitro effects and acceptable toxicity, oral dextran sulfate as a potential antiretroviral agent continues to be studied. [ABSTRACT FROM AUTHOR]

This interesting study is part of a larger project on burnout in dentistry, parts of which have been published before. The possible long-term consequences of occupational stress were studied. Burnout is regarded as a syndrome with 3 distinct aspects: emotional exhaustion, depersonalization (cynical attitude toward one's patients), and reduced personal accomplishment. The hypothesis in this study was that dentists with a high burnout risk would have more health complaints and show more unhealthy behavior than dentists with a low burnout risk. A representative group (75%) of 708 (594 male and 114 female) actively practicing dentists responded to a questionnaire, the Dutch version of the Maslach Burnout Inventory, a health complaints measure, and items on health behavior. Results showed that dentists with a high burnout risk reported health complaints to a greater extent than did dentists with a low burnout risk. They also reported more unhealthy behavior in some aspects (less physical exercise, increase in alcohol consumption, unhealthy diet), but not in others. One of 10 dentists reported having poor general health, and 3 of 10 reported a poor physical condition. In comparison with the general Dutch population, the dentists' self-reports appeared be more favorable. The conclusion was that among dentists, burnout and poor health are strongly related; dealing preventively with the burnout problem in dentistry and paying attention to physical health, including ergonomics, are essential. [ABSTRACT FROM AUTHOR]

Background Digital technologies are proliferating into dental practices. While their technical attributes have often been studied, it remains unclear why some dentists adopt and use these technologies more than others.Aim To explore the incentives for and barriers against accepting and using digital dental technologies.Method Eleven semi-structured qualitative interviews were conducted with experts in dentistry, dental technology and dental education in the Netherlands. Results Dentists' acceptance and use of digital technologies are to varying degrees driven by the perceived advantages over analogue methods, perceived influence on treatment quality, dentists' personal and professional orientation, and social influence from peers and external groups. These effects are complemented by personal and dental-practice characteristics. Conclusions The findings suggest that there are large differences in motivation to adopt and use digital technologies between early adopters, late adopters and non-adopters, which should be examined in greater detail. We recommend that educators, dentists, and representatives of the dental industry who deal with the diffusion of these technologies take account of dentists' widely different attitudes to digitalisation. [ABSTRACT FROM AUTHOR]