Association between periodontal disease and subclinical atherosclerosis: the ELSA-Brasil study

The aim of this study was to investigate the relationship between periodontal disease and increased thickness of the carotid artery intima-media complex. A cross-sectional study was conducted with 220 adults (age ≥ 35 years) among participants in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Carotid artery ultrasound and periodontal clinical examinations were conducted and included visible plaque index, gingival bleeding on probing index, probing pocket depth (PPD), and clinical attachment level (CAL). Individuals with increased carotid artery thickness showed fewer teeth and higher frequency of CAL ≥ 3mm, CAL ≥ 4mm, CAL ≥ 5mm, and CAL ≥ 6mm and PPD ≥ 4mm (p < 0.05). Despite the use of 18 definitions for periodontal disease, only one confirmed the hypothesis of an association between periodontal disease and subclinical atherosclerosis. Individuals with 10% or more sites with CAL ≥ 4mm were more likely to present carotid thickening.     

Risk of high‐level viraemia in HIV‐infected patients on successful antiretroviral treatment for more than 6 months

Objectives

According to the Swiss Federal Commission for HIV/AIDS, HIV‐infected patients on successful antiretroviral treatment have a negligible risk of transmitting HIV sexually. We estimated the risk that patients considered to have an undetectable viral load (VL) are actually viraemic.

Methods

A Danish, population‐based nationwide cohort study of HIV‐infected patients with VL <51 HIV‐1 RNA copies/mL for more than 6 months was carried out for the study period 2000–2008. The observation time was calculated from 6 months after the first VL <51 copies/mL to the last measurement of VL or the first VL >50 copies/mL. The time at risk of transmitting HIV sexually was calculated as 50% of the time from the last VL <51 copies/mL to the subsequent VL if it was >1000 copies/mL. The outcome was the time at risk of transmitting HIV sexually divided by the observation time.

Results

We identified 2680 study subjects contributing 9347.7 years of observation time and 56.4 years of risk of transmitting HIV (VL>1000 copies/mL). In 0.6% [95% confidence interval (CI) 0.5–0.8%] of the overall observation time the patients had VL >1000 copies/mL. In the first 6 months this risk was substantially higher (7.9%; 95% CI 4.5–11.0%), but thereafter decreased and was almost negligible after 5 years (0.03%; 95% CI 0.0–0.2%). The risk was higher in injecting drug users, but otherwise did not differ between subgroups of patients.

Conclusion

The risk of viraemia and therefore the risk of transmitting HIV sexually are high in the first 12 months of successful antiretroviral treatment, but thereafter are low.     

Parvovirus B19 infection in patients with hemophilia

BACKGROUND: The long-term consequences of parvovirus B19 infection in transfusion recipients are not known, and thus the value of B19 screening of blood donors remains unresolved. Hemophiliacs, at risk for B19 through their chronic exposure to clotting factor concentrates, have frequent, close medical follow-up and thereby constitute an ideal group in which to study the hematologic sequelae of B19 infection. STUDY DESIGN AND METHODS: An enzyme-linked immunosorbent assay was used to detect B19 IgG and IgM and the polymerase chain reaction was used to detect B19 DNA in frozen, stored plasma samples, obtained between 1987 and 1994, from 136 subjects with hemophilia, including 71 who were human immunodeficiency virus (HIV)-positive and 65 who were HIV- negative. Then the results of the tests were compared with clinical hematological data and blood product usage data. RESULTS: B19 seroprevalence in the hemophilic cohort was 81.6 percent (111/136), including 74.6 percent (53/71) of HIV-positive and 89.2 percent (58/65) of HIV-negative hemophiliacs. It was not affected by age, type or severity of hemophilia, HIV status, CD4 number, or yearly blood product usage. Only 1 (0.7%) of the 136 samples was positive for B19 IgM and none was positive in polymerase chain reaction for B19 DNA. After adjusting for HIV status, there were no differences between B19- positive and B19-negative hemophiliacs in hematologic values, CD4 counts, or blood product use. CONCLUSION: Although B19 IgG seroprevalence in this hemophilic cohort is high and indicative of past B19 infection, there is no detectable B19 viral activity or any associated long-term clinical or hematologic sequelae.     

Toxicity induced by nanoparticles

Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics.     

Development and pretesting of an electronic learning module to train health care professionals on the use of the Pediatric Respiratory Assessment Measure to assess acute asthma severity

BACKGROUND:

Severity-specific guidelines based on the Pediatric Respiratory Assessment Measure (PRAM), a validated clinical score, reduce pediatric asthma hospitalization rates.

OBJECTIVE:

To develop, pretest the educational value of and revise an electronic learning module to train health care professionals on the use of the PRAM.

METHODS:

The respiratory efforts of 32 children with acute asthma were videotaped and pulmonary auscultation was recorded. A pilot module, composed of a tutorial and 18 clinical cases, was developed in French and English. Health care professionals completed the module and provided feedback. The performance of participants, case quality and difficulty, and learning curve were assessed using the Rasch test; quantitative and qualitative feedback served to revise the module.

RESULTS:

Seventy-two participants (19 physicians, 22 nurses, four respiratory therapists and 27 health care trainees) with a balanced distribution across self-declared expertise (26% beginner, 35% competent and 39% expert) were included. The accuracy of experts was superior to beginners (OR 1.79, 1.15 and 2.79, respectively). Overall performance significantly improved between the first and latter half of cases (P<0.001). Participants assessed the module to be clear (96%), relevant (98%), realistic (94%) and useful (99%) to learn the PRAM. The qualitative/quantitative analysis led to the deletion of three cases, modification of remaining cases to further enhance quality and reordering within three levels of difficulty.

DISCUSSION:

Using rigorous educational methods, an electronic module was developed to teach health care professionals on use of the PRAM score. Using the back-translation technique, both French and English versions were developed and validated simultaneously. The pilot module comprised a tutorial and three case-scenario sections, and was tested on a target audience of physicians, nurses, respiratory therapists and medical trainees.

CONCLUSION:

The final electronic learning module met the clarity and quality requirements of a good teaching tool, with a demonstrated learning effect and high appreciation by health care professionals. Available in French and English, it is offered to facilitate implementation of PRAM-based acute pediatric asthma guidelines.     

Human immunodeficiency virus-related conditions in children and adults with hemophilia: rates, relationship to CD4 counts, and predictive value

To further elucidate the natural history of human immunodeficiency virus (HIV) infection, we studied intermediate HIV-related conditions occurring before acquired immunodeficiency syndrome (AIDS) in a prospectively observed multicenter cohort of 738 HIV-infected persons with hemophilia. We analyzed the frequency in adults and children of common HIV-related conditions and the relative risk of AIDS after occurrence of these conditions, controlling for age at seroconversion and the percentage of CD4+ lymphocytes. Thrombocytopenia was the most frequently observed condition with cumulative incidences of 43% +/- 7% in adults and 27% +/- 6% in children and adolescents by 10 years after seroconversion. Oral candidiasis, fever, weight loss, and non-AIDS pneumonia were two to four times more common in adults than children, whereas herpes zoster risk was similar in the two age groups. HIV- related conditions were infrequent during the first 4 years of infection, particularly in children. With the exception of thrombocytopenia, mean CD4 counts were less than 350 cells/microL at the onset of the conditions. The relative hazard of AIDS after oral candidiasis was 18 in children and 3.8 in adults. Relative hazard in adults was also increased after persistent fever (10), weight loss (3.2), and non-AIDS pneumonia (2.2). Herpes zoster and thrombocytopenia were not significantly associated with AIDS in either age group. We conclude that intermediate HIV-related conditions occur more frequently in adults than in children with hemophilia. Persistent fever is the strongest predictor of AIDS in adults, whereas oral candidiasis is the strongest predictor in children. These findings should facilitate the design and conduct of clinical trials as well as the management of HIV- infected children and adults.     

The presence of hepatitis C virus (HCV) antibody in human immunodeficiency virus-positive hemophilic men undergoing HCV "seroreversion"

Hepatitis C virus (HCV) is a major cause of transfusion-induced chronic liver disease in hemophiliacs, with 70% to 90% being anti-HCV positive. Seroreversion or loss of antibody response to HCV has been observed in a small proportion of human immunodeficiency virus-positive [HIV(+)] anti-HCV(+) hemophilic men. Despite the seroreversion to an anti-HCV- negative state, such patients continue to show serum alanine aminotransferase (ALT) elevations and biopsy evidence of cirrhosis and/or chronic active hepatitis. To determine the cause for the loss of anti-HCV antibody, we compared first- and second-generation anti-HCV enzyme immunosorbent assay (EIA 1.0 and 2.0), second-generation recombinant immunoblot (RIBA 2.0), and HCV-RNA amplification using polymerase chain reaction (PCR) in 19 "seroreverters" before and after seroreversion. There was no difference between 19 seroreverters and 59 persistently anti-HCV-positive hemophiliacs in mean ALT (1.1 +/- 0.1 XUL v 2.0 +/- 0.2 XUL; chi 2 = 1.80, P > .05), in mean CD4 (188 +/- 36/microL v 232 +/- 28/microL; t = 0.965, P > .05), or in the rate of progression to acquired immunodeficiency syndrome (13 of 19 [68.4%] v 30 of 59 [50.9%]; chi 2 = .987, P > .05, respectively). Before seroreversion, all 19 seroreverters (100%) were positive for EIA 1.0 and 2.0 and PCR, and all but 2 of 19 (89.5%) were RIBA 2.0 positive, whereas, after seroreversion, none were positive for EIA 1.0, 15 of 19 (78.9%) were positive for EIA 2.0, 8 of 18 (44.4%) were positive for RIBA 2.0, and 18 of 19 (94.7%) were positive for PCR. There was a lower CD4 lymphocyte number after seroreversion in those who were RIBA 2.0 negative as compared with those who were RIBA 2.0 positive (32 +/- 10/microL v 171 +/- 52/microL; t = 2.638, P > .05). These results indicate that HIV(+) anti-HCV(+) hemophilic men who undergo "HCV seroreversion" are truly infectious and anti-HCV positive by second- generation tests. Anti-HCV detection in immunosuppressed hosts is significantly improved by second-generation EIA and RIBA assays.     

Role of spleen in hereditary spherocytosis: evidence for increased in vitro proteolysis of red cell membrane

In vitro proteolysis of red cell membranes has been studied by means of electrophoretic separation on SDS-polyacrylamide gel of solubilized ghost proteins and subsequent densitometry of separated, stained bands; the amounts of major membrane proteins were measured in ghosts either with inhibited or with allowed proteolysis in the following cases: 15 patients suffering from hereditary spherocytosis (HS) with variable degree of spleen enlargement, eight cirrhotic patients with spleen enlargement and 12 healthy blood donors as control group. Proteolysis was present to a greater extent in HS patients with larger splenomegaly, lesser in HS with smaller splenomegaly, and was comparable to healthy controls both in splenectomized HS and in patients with spleen enlargement due to liver cirrhosis. The results suggest the involvement of splenomegaly in the enhancement of in vitro proteolysis in HS red cell membrane; it is probably attributable to joint effects of the damage induced in red cells by prolonged retention within haemolysing spleen together with the abnormalities genetically affecting the structure of HS red cell membrane.     

Multimorbidity patterns of oral clinical conditions,social position,and oral health‐related quality of life in a population‐based survey of 12‐yr‐old children

The aim of this study was to describe the patterns of multimorbidities of oral clinical conditions in children. The association between social position and number of oral clinical conditions, and the relationship of social position and number of oral clinical conditions with oral health‐related quality of life [OHRQoL, measured using the Brazilian Child‐Oral Impacts on Daily Performance (Child‐OIDP)] were also investigated. The study analysed data on 7,208 children, 12 yr of age, from the Brazilian Oral Health Survey (SBBrasil Project). Cluster analysis based on the observed/expected (O/E) ratios identified six significant clusters of oral clinical conditions: (i) dental caries and missing teeth; (ii) dental caries and dental trauma; (iii) dental trauma and gingivitis; (iv) dental caries, missing teeth, and dental trauma; (v) dental caries, dental trauma, and gingivitis; and (vi) all oral clinical conditions. Ordinal regression showed that poor social position was associated with a large number of oral clinical conditions. Poisson regression demonstrated that low social position and greater number of oral clinical conditions increased the likelihood of poor OHRQoL (Child‐OIDP extent). The four oral clinical conditions clustered into six distinct clusters among Brazilian children. Multimorbidity of oral clinical conditions predicted poor OHRQoL. Social position was of high relevance to multimorbidity of oral clinical conditions and children′s OHRQoL.