Trypanosoma cruzi inactivation in human platelet concentrates and plasma by a psoralen (amotosalen HCl) and long-wavelength UV

Trypanosoma cruzi, the protozoan pathogen that causes Chagas' disease, can be found in the blood of infected individuals for their entire life span. This presents a serious challenge in safeguarding blood products. Transmission of T. cruzi from blood products is a frequent occurrence in Latin America, where Chagas' disease is endemic. This study was designed to determine whether T. cruzi could be inactivated in human platelet concentrates and plasma by a photochemical treatment process with long-wavelength UV A light (UVA, 320 to 400 nm) plus the psoralen amotosalen HCl (Cerus Corporation). Units of platelet concentrates (300 ml) and plasma (300 ml) were intentionally contaminated with approximately 10(6) T. cruzi trypomastigotes, the T. cruzi form found in the bloodstream, per ml. The viability of T. cruzi after photochemical inactivation was determined by their ability to replicate in 3T3 fibroblasts. Controls, including treatment with 150 micro M amotosalen or 3 J/cm(2) UVA alone, did not lead to reduction of the viability of T. cruzi in plasma or platelet concentrates. However, treatment with 150 micro M amotosalen plus 3 J/cm(2) UVA inactivated T. cruzi to undetectable levels in plasma and platelet concentrates. This represented a >5.4-log reduction of T. cruzi in platelet concentrates and >5.0-log reduction of T. cruzi in plasma. We conclude that the amotosalen plus UVA photochemical inactivation technology is effective in inactivating high levels of protozoan pathogens, such as T. cruzi, in platelet concentrates and plasma, as has been previously shown for numerous viruses and bacteria.     

Swimming without the water: A critical perspective on mental health experience for adult nursing students

Adult nurses and adult field nursing students come into contact with a diverse range of other patient groups in their practice but perhaps none more so than those who have co-existing mental health issues. Consequently adult field student nurses must be equipped with the requisite knowledge and skills to competently care for their patients who also experience mental health problems. Given the pressure on placements many education providers have developed alternatives to direct mental health experiences. The authors review their own experience of some of the modalities that higher education institutes (HEI) use to instruct their students in this field. They argue that, ideally, there is no substitute for the practical experience of placements in the mental health sector, particularly if these include contact with mental health nursing. The paper concludes with some recommendations for nursing education and our professional body that could help equip adult field nursing students with the necessary experience and skills of mental health to support them into their future careers.     

Factors associated with the provision of anti-smoking advice in general practice consultations.

Guidelines urge general practitioners (GPs) to discuss smoking with patients as frequently as possible. Using data collected before and after consultations, this study confirms that GPs are more likely to discuss smoking in the context of smoking-related problems. Encouraging GPs to make greater use of problem-orientated opportunities to discuss smoking may have more effect on rates of advice giving than urging them to advise all smokers.     

Protein intake is not associated with functional biomarkers of physical frailty: A cross-sectional analysis of community-dwelling older adults with type 2 diabetes mellitus

Background and aimFrailty has emerged as a third category of complication in patients with type 2 diabetes mellitus (T2DM). It has been suggested that adequate protein intake is an important dietary strategy for counteracting frailty. Therefore, we explored the association between protein intake and functional biomarkers of frailty in older adults with T2DM.Methods and resultsFrailty was operationalized as the presence of three of the following: exhaustion, low muscle strength, low physical activity, slow gait speed, and weight loss. Functional biomarkers included handgrip strength (HGS), chair stands, the short physical performance battery and gait speed. Eighty-seven older adults (71.2 ± 8.2 years; 66.7% males) were included. A total of n = 6 (~7%) and n = 32 (~37%) participants were identified as frail and pre-frail respectively. No significant difference was observed for protein intake across staging of frailty (pre-frail/frail: 1.3 ± 0.4 g/kg BW; non-frail: 1.4 ± 0.4 g/kg BW; P = 0.320). A significant association was observed for total protein intake and HGS (β = 0.44; 95% CI: 0.23–1.8; P = 0.01). However, this was no longer significant after adjusting for age, gender, physical activity, energy intake and total appendicular lean muscle (β = 0.03; 95% CI: ?0.45–0.60; P = 0.78). Nil other associations were observed between total protein intake and functional biomarkers of frailty.ConclusionAdequate protein intake was not associated with functional biomarkers in older adults with T2DM. Future research should focus on the efficacy of protein on attenuating functional decline in vulnerable older adults with low protein intake.     

Absence of Toxemia in Clostridioides difficile Infection: Results from Ultrasensitive Toxin Assay of Serum

Digestive Diseases and Sciences - Clostridioides difficile infection (CDI) is caused by Toxins A and B, secreted from pathogenic strains of C. difficle. This infection can vary greatly in symptom...     

A miniature quantitative PCR device for directly monitoring a sample processing on a microfluidic rapid DNA system

We report a microfluidic device and measurement method to perform real-time PCR (or qPCR) in a miniaturized configuration for on-chip implementation using reaction volumes of less than 20 μL. The qPCR bioreactor is designed as a module to be embedded in an automated sample-in/profile-out system for rapid DNA biometrics or human identification. The PCR mixture is excited with a 505 nm diode-pumped solid-state laser (DPSSL) and the fluorescence build-up is measured using optical fibers directly embedded to the sidewalls of the microfluidic qPCR bioreactor. We discuss manufacturing and operating parameters necessary to adjust the internal surface conditions and temperature profiles of the bioreactor and to optimize the yield and quality of the PCR reaction for the amplification of 62 bp hTERT intron fragments using the commercial Quantifiler® kit (Life Technologies, Carlsbad, CA) commonly accepted for genotyping analysis. We designed a microfluidic device suitable for continuously processing a specimen by efficiently mixing the reagents from the kit to a set volume of DNA template on chip. Our approach relies on a calibration curve for the specific device using control DNA. We successfully applied this method to determine the concentration of genomic DNA extracted from a buccal swab on separate microfluidic devices which are operated upstream the qPCR device and perform buccal swab lysis and buccal DNA extraction. A precise correlation between the amount determined on chip and that obtained using a commercial cycler is demonstrated.     

Safety and Immunogenicity of a Vero Cell Culture-Derived Whole-Virus H5N1 Influenza Vaccine in Chronically Ill and Immunocompromised Patients

The development of vaccines against H5N1 influenza A viruses is a cornerstone of pandemic preparedness. Clinical trials of H5N1 vaccines have been undertaken in healthy subjects, but studies in risk groups have been lacking. In this study, the immunogenicity and safety of a nonadjuvanted cell culture-derived whole-virus H5N1 vaccine were assessed in chronically ill and immunocompromised adults. Subjects received two priming immunizations with a clade 1 A/Vietnam H5N1 influenza vaccine, and a subset also received a booster immunization with a clade 2.1 A/Indonesia H5N1 vaccine 12 to 24 months later. The antibody responses in the two populations were assessed by virus neutralization and single radial hemolysis assays. The T-cell responses in a subset of immunocompromised patients were assessed by enzyme-linked immunosorbent spot assay (ELISPOT). The priming and the booster vaccinations were safe and well tolerated in the two risk populations, and adverse reactions were predominantly mild and transient. The priming immunizations induced neutralizing antibody titers of ≥1:20 against the A/Vietnam strain in 64.2% of the chronically ill and 41.5% of the immunocompromised subjects. After the booster vaccination, neutralizing antibody titers of ≥1:20 against the A/Vietnam and A/Indonesia strains were achieved in 77.5% and 70.8%, respectively, of chronically ill subjects and in 71.6% and 67.5%, respectively, of immunocompromised subjects. The T-cell responses against the two H5N1 strains increased significantly over the baseline values. Substantial heterosubtypic T-cell responses were elicited against the 2009 pandemic H1N1 virus and seasonal A(H1N1), A(H3N2), and B subtypes. There was a significant correlation between T-cell responses and neutralizing antibody titers. These data indicate that nonadjuvanted whole-virus cell culture-derived H5N1 influenza vaccines are suitable for immunizing chronically ill and immunocompromised populations. (This study is registered at ClinicalTrials.gov under registration no. {"type":"clinical-trial","attrs":{"text":"NCT00711295","term_id":"NCT00711295"}}NCT00711295.)     

In vitro activity of E-4868, a new trifluoroquinolone,compared to six similar compounds

The compound E-4868 (Laboratorios Dr. Esteve) is a trifluoro, 7-azetidinyl quinolone with properties resembling those of other fluoroquinolones. Its activity in vitro was compared to that of six other similar drugs against more than 700 nosocomial isolates using standard methods. The MIC50s of E-4868 for enteric bacilli ranged from 0.015 to 0.25 µg/ml, being highest forProvidencia spp.Pseudomonas aeruginosa strains were two-fold more susceptible to E-4868 than to ofloxacin. MICs of E-4868 forHaemophilus influenzae, Moraxella catarrhalis and pathogenicNeisseria spp. were all 0.12 µg/ml. E-4868 was equal in activity to or eight-fold more active than ciprofloxacin against gram-positive cocci. The MICs of E-4868 for pneumococci were all 0.5 µg/ml but anaerobes such asBacteroides fragilis were generally less susceptible (MIC90, 4 µg/ml). There was almost complete cross-resistance to several other fluoroquinolones. Resistant mutants were selected by a multiple passage technique but the rate of mutation to resistance was very low (< 10^–8) at an 8 x MIC.