Stage-dependent production and release of histidine-rich protein 2 by Plasmodium falciparum

Because of their sequestration in the microcirculation, the pathogenic late stages of Plasmodium falciparum are under-represented in peripheral blood samples from patients with falciparum malaria. Excreted products of the parasite might help to estimate this sequestered biomass. We quantified the stage-dependent production and release per parasite of P. falciparum histidine-rich protein 2 (PfHRP2) with the objective of measuring the sequestered biomass. A simple method to relate parasite stage to parasite age was developed to facilitate this. In four isolates of P. falciparum, the median (range) PfHRP2 content was 2.0fg (0.5-4.3fg) for a young ring stage infected erythrocyte, and 5.4fg (2.1-10.2fg) for the schizont stage. The amount of PfHRP2 in the parasitized erythrocyte increased most during development to the mature trophozoite stage. The median (range) amount of PfHRP2 secreted per parasite per entire erythrocytic cycle was 5.2fg (1.1-13.0fg). A median of 89% of the total PfHRP2 was excreted at the moment of schizont rupture. This assessment of the stage-dependent release of PfHRP2 is an essential prerequisite for future studies aimed at estimating the total patient parasite mass from the peripheral blood PfHRP2 concentration.     

Assessing publication bias in meta-analysis

BACKGROUND: Although publication bias is a concern when using meta-analysis, techniques for assessing for its potential appear to be underused in nursing. OBJECTIVES: To demonstrate several methods, both graphical and statistical, of assessing for publication bias. METHODS: Four methods are described and demonstrated, ranging from the familiar fail-safe N to the trim-and-fill method, using the same contrived data set. RESULTS: Methods vary in their conclusion about the presence of potential publication bias in the example presented. Some limitations of the methods are noted to assist meta-analysts in determining which to consider using. CONCLUSION: Given that publication bias can affect the validity of meta-analytic studies, researchers are encouraged to use more than one method to assess for bias so that clinicians and decision-makers can have the best possible information available.     

Comparison of a slide agglutination test, LeptoTek Dri-Dot, and IgM-ELISA with microscopic agglutination test for Leptospira antibody detection

A slide agglutination test (SAT), LeptoTek Dri-Dot and IgM-ELISA were compared with a microscopic agglutination test (MAT) for the detection of Leptospira antibodies. Paired sera from 10 patients whose leptospirosis was clinically suspected and diagnosed by MAT, were evaluated in this study. Our data, especially from acute samples, demonstrate the SAT and Dri-Dot were more sensitive as initial screening tests than MAT. IgM-ELISA has an advantage over MAT, SAT, and Dri-Dot since the results can be interpreted from a single serum testing if the results of the test are positive. Eight of the ten cases could be diagnosed by IgM-ELISA. Our data suggest that IgM-ELISA may be used for the diagnosis of leptospirosis. However, the agglutination test is useful for screening and for secondary infection cases for which IgM antibodies may be undetectable. MAT can be performed as a reference test and when information regarding the causative serovar is required.     

Viral hepatitis infections among dialysis patients: Thailand registry report

BACKGROUND: Patients on dialysis are at high risk of acquiring viral hepatitis infections. However, there were only few data from Thailand. The aim of the present study was to assess the prevalence, incidence and associated risk factors of viral hepatitis infections among dialysis patients. METHODS: A retrospective study was conducted to evaluate 5179 medical records of dialysis patients from the Thailand Renal Replacement Therapy Registry. RESULTS: In 2002, the seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections were 6.3% (n = 2454) and 4.8% (n = 2167), respectively. HBV and HCV seroprevalence became 6.5% (n = 2585) and 4.3% (n = 2399) in 2003. The incidence of HBV and HCV infections were 1.5 and 2.4 cases per 1000 patient-years, respectively. Logistic regression analysis showed that age and gender were significant risk factors for HBV infection, but not for HCV infection. CONCLUSION: In Thailand, it was not uncommon for dialysis patients to acquire viral hepatitis infections. However, our prevalence is similar to reports from some other South-East Asian countries.     

Medications That Cause Dry Mouth As an Adverse Effect in Older People: A Systematic Review and Metaanalysis

Objectives

To assess and quantify the risk of drug‐induced dry mouth as a side effect in older people.

Design

Systematic review and metaanalysis.

Setting

A search of the literature was undertaken using Medline, Embase, Cochrane, Web of Science, and PubMed from 1990 to 2016.

Participants

Older people (aged ≥60) who participated in intervention or observational studies investigating drug use as an exposure and xerostomia or salivary gland hypofunction as adverse drug outcomes.

Measurements

Two pairs of authors screened titles and abstracts of studies for relevance. Two authors independently extracted data, including study characteristics, definitions of exposure and outcome, and methodological quality. For the metaanalyses, random‐effects models were used for pooling the data and I² statistics for exploring heterogeneity.

Results

Of 1,544 potentially relevant studies, 52 were deemed eligible for inclusion in the final review and 26 in metaanalyses. The majority of studies were of moderate methodological quality. In the intervention studies, urological medications (odds ratio (OR) = 5.91, 95% confidence interval (CI) = 4.04–8.63; I² = 62%), antidepressants (OR = 4.74, 95% CI = 2.69–8.32, I² = 21%), and psycholeptics (OR = 2.59, 95% CI = 1.79–3.95, I² = 0%) were significantly associated with dry mouth. In the observational studies, numbers of medications and several medication classes were significantly associated with xerostomia and salivary gland hypofunction.

Conclusion

Medication use was significantly associated with xerostomia and salivary gland hypofunction in older adults. The risk of dry mouth was greatest for drugs used for urinary incontinence. Future research should develop a risk score for medication‐induced dry mouth to assist with prescribing and medication management.     

MRI findings in acute disseminated encephalomyelitis following varicella infection in an adult

There are no abnormal magnetic resonance imaging (MRI) findings in children with acute disseminated encephalomyelitis (ADEM) after varicella infection. Here, we report abnormal MRI findings in an adult, namely: hyperintense signal in the right medullary olive, the right side of the pons, the left middle cerebellar peduncle, the dorsal aspect of both thalami and the periventricular white matter of both cerebral hemispheres. The patient's condition improved after 1 week of corticosteroid treatment. Four months later, MRI of the brain showed almost complete resolution and there were no further attacks of motor weakness at 18-months follow-up.