Portable sample processing for molecular assays: application to Zika virus diagnostics

This paper introduces a digital microfluidic (DMF) platform for portable, automated, and integrated Zika viral RNA extraction and amplification. The platform features reconfigurable DMF cartridges offering a closed, humidified environment for sample processing at elevated temperatures, as well as programmable control instrumentation with a novel thermal cycling unit regulated using a proportional integral derivative (PID) feedback loop. The system operates on 12 V DC power, which can be supplied by rechargeable battery packs for remote testing. The DMF system was optimized for an RNA processing pipeline consisting of the following steps: 1) magnetic-bead based RNA extraction from lysed plasma samples, 2) RNA clean-up, and 3) integrated, isothermal amplification of Zika RNA. The DMF pipeline was coupled to a paper-based, colorimetric cell-free protein expression assay for amplified Zika RNA mediated by toehold switch-based sensors. Blinded laboratory evaluation of Zika RNA spiked in human plasma yielded a sensitivity and specificity of 100% and 75% respectively. The platform was then transported to Recife, Brazil for evaluation with infectious Zika viruses, which were detected at the 100 PFU mL^-1 level from a 5 μL sample (equivalent to an RT-qPCR cycle threshold value of 32.0), demonstrating its potential as a sample processing platform for miniaturized diagnostic testing.

The effect of smoking on COVID-19 severity: A systematic review and meta-analysis

Various comorbidities represent risk factors for severe coronavirus disease 2019 (COVID‐19). The impact of smoking on COVID‐19 severity has been previously reported in several meta‐analyses limited by small sample sizes and poor methodology. We aimed to rigorously and definitively quantify the effects of smoking on COVID‐19 severity. MEDLINE, Embase, CENTRAL, and Web of Science were searched between 1 December 2019 and 2 June 2020. Studies reporting smoking status of hospitalized patients with different severities of disease and/or at least one clinical endpoint of interest (disease progression, intensive care unit admission, need for mechanical ventilation, and mortality) were included. Data were pooled using a random‐effects model. This study was registered on PROSPERO: CRD42020180920. We analyzed 47 eligible studies reporting on 32 849 hospitalized COVID‐19 patients, with 8417 (25.6%) reporting a smoking history, comprising 1501 current smokers, 5676 former smokers, and 1240 unspecified smokers. Current smokers had an increased risk of severe COVID‐19 (risk ratios [RR]: 1.80; 95% confidence interval [CI]: 1.14‐2.85; P = .012), and severe or critical COVID‐19 (RR: 1.98; CI: 1.16‐3.38; P = .012). Patients with a smoking history had a significantly increased risk of severe COVID‐19 (RR: 1.31; CI: 1.12‐1.54; P = .001), severe or critical COVID‐19 (RR: 1.35; CI: 1.19‐1.53; P < .0001), in‐hospital mortality (RR: 1.26; CI: 1.20‐1.32; P < .0001), disease progression (RR: 2.18; CI: 1.06‐4.49; P = .035), and need for mechanical ventilation (RR: 1.20; CI: 1.01‐1.42; P = .043). Patients with any smoking history are vulnerable to severe COVID‐19 and worse in‐hospital outcomes. In the absence of current targeted therapies, preventative, and supportive strategies to reduce morbidity and mortality in current and former smokers are crucial.

The first high‐quality systematic review and meta‐analysis assessing the impact of smoking on COVID‐19 severity.

To date, the largest meta‐analysis among peer‐reviewed literature assessing the impact of smoking on COVID‐19 severity, including 32,849 hospitalised patients with COVID‐19.

Patients who were current smokers had an increased risk of severe COVID‐19 and severe or critical COVID‐19.

Patients with a smoking history had an increased risk of severe COVID‐19, severe or critical COVID‐19, in‐hospital mortality, disease progression and need for mechanical ventilation.

Population-Based Quality Indicators for End-of-Life Cancer Care: A Systematic Review

Importance

Improving the quality of cancer care is an international priority. Population-based quality indicators (QIs) are key to this process yet remain almost exclusively used for evaluating care during the early, often curative, stages of disease.

Objectives

To identify all existing QIs for the care of patients with cancer who have advanced disease and/or are at the end of life and to evaluate each indicator's measurement properties and appropriateness for use.

Evidence Review

For this systematic review, 5 electronic databases (MEDLINE, Embase, CINAHL, PsycINFO, and the Cochrane Library) were searched from inception through February 4, 2019, for studies describing the development, review, and/or testing of QIs for the care of patients with cancer who have advanced disease and/or are at the end of life. For each QI identified, descriptive information was extracted and 6 measurement properties (acceptability, evidence base, definition, feasibility, reliability, and validity) were assessed using previously established criteria, with 4 possible ratings: positive, intermediate, negative, and unknown. Ratings were collated and each QI classified as appropriate for use, inappropriate for use, or of limited testing. Among the QIs determined as appropriate for use, a recommended shortlist was generated by excluding those that were specific to patient subgroups and/or care settings; related QIs were identified, and the indicator with the highest rating was retained.

Findings

The search yielded 7231 references, 35 of which (from 28 individual studies) met the eligibility criteria. Of 288 QIs extracted (260 unique), 103 (35.8%) evaluated physical aspects of care and 109 (37.8%) evaluated processes of care. Quality indicators relevant to psychosocial (18 [6.3%]) or spiritual and cultural (3 [1.0%]) care domains were limited. Eighty QIs (27.8%) were determined to be appropriate for use, 116 (40.3%) inappropriate for use, and 92 (31.9%) of limited testing. The measurement properties with the fewest positive assessments were acceptability (38 [13.2%]) and validity (63 [21.9%]). Benchmarking data were reported for only 16 QIs (5.6%). The final 15 recommended QIs came from 6 studies.

Conclusions and Relevance

The findings suggest that only a small proportion of QIs developed for the care of patients with cancer who have advanced disease and/or are at the end of life have received adequate testing and/or are appropriate for use. Further testing may be needed, as is research to establish benchmarking data and to expand QIs relevant to psychosocial, cultural, and spiritual care domains.

Association of adverse perinatal outcomes of intrahepatic cholestasis of pregnancy with biochemical markers: results of aggregate and individual patient data meta-analyses

BACKGROUND

Intrahepatic cholestasis of pregnancy is associated with adverse perinatal outcomes, but the association with the concentration of specific biochemical markers is unclear. We aimed to quantify the adverse perinatal effects of intrahepatic cholestasis of pregnancy in women with increased serum bile acid concentrations and determine whether elevated bile acid concentrations were associated with the risk of stillbirth and preterm birth.

METHODS

We did a systematic review by searching PubMed, Web of Science, and Embase databases for studies published from database inception to June 1, 2018, reporting perinatal outcomes for women with intrahepatic cholestasis of pregnancy when serum bile acid concentrations were available. Inclusion criteria were studies defining intrahepatic cholestasis of pregnancy based upon pruritus and elevated serum bile acid concentrations, with or without raised liver aminotransferase concentrations. Eligible studies were case-control, cohort, and population-based studies, and randomised controlled trials, with at least 30 participants, and that reported bile acid concentrations and perinatal outcomes. Studies at potential higher risk of reporter bias were excluded, including case reports, studies not comprising cohorts, or successive cases seen in a unit; we also excluded studies with high risk of bias from groups selected (eg, a subgroup of babies with poor outcomes were explicitly excluded), conference abstracts, and Letters to the Editor without clear peer review. We also included unpublished data from two UK hospitals. We did a random effects meta-analysis to determine risk of adverse perinatal outcomes. Aggregate data for maternal and perinatal outcomes were extracted from case-control studies, and individual patient data (IPD) were requested from study authors for all types of study (as no control group was required for the IPD analysis) to assess associations between biochemical markers and adverse outcomes using logistic and stepwise logistic regression. This study is registered with PROSPERO, number CRD42017069134.

FINDINGS

We assessed 109 full-text articles, of which 23 studies were eligible for the aggregate data meta-analysis (5557 intrahepatic cholestasis of pregnancy cases and 165 136 controls), and 27 provided IPD (5269 intrahepatic cholestasis of pregnancy cases). Stillbirth occurred in 45 (0·83%) of 4936 intrahepatic cholestasis of pregnancy cases and 519 (0·32%) of 163 947 control pregnancies (odds ratio [OR] 1·46 [95% CI 0·73-2·89]; I2=59·8%). In singleton pregnancies, stillbirth was associated with maximum total bile acid concentration (area under the receiver operating characteristic curve [ROC AUC]) 0·83 [95% CI 0·74-0·92]), but not alanine aminotransferase (ROC AUC 0·46 [0·35-0·57]). For singleton pregnancies, the prevalence of stillbirth was three (0·13%; 95% CI 0·02-0·38) of 2310 intrahepatic cholestasis of pregnancy cases in women with serum total bile acids of less than 40 μmol/L versus four (0·28%; 0·08-0·72) of 1412 cases with total bile acids of 40-99 μmol/L (hazard ratio [HR] 2·35 [95% CI 0·52-10·50]; p=0·26), and versus 18 (3·44%; 2·05-5·37) of 524 cases for bile acids of 100 μmol/L or more (HR 30·50 [8·83-105·30]; p<0·0001).

INTERPRETATION

The risk of stillbirth is increased in women with intrahepatic cholestasis of pregnancy and singleton pregnancies when serum bile acids concentrations are of 100 μmol/L or more. Because most women with intrahepatic cholestasis of pregnancy have bile acids below this concentration, they can probably be reassured that the risk of stillbirth is similar to that of pregnant women in the general population, provided repeat bile acid testing is done until delivery.

FUNDING

Tommy's, ICP Support, UK National Institute of Health Research, Wellcome Trust, and Genesis Research Trust.

[Combined cystectomy of the ramus with sagittal split osteotomy in mandibular asymmetry]

A case of typical mandibular asymmetry, probably caused by the development of a primordial cyst in the right ramus of the mandible, is presented. The one stage operation performed, which enabled the enucleation of the cyst and the simultaneous correction of the asymmetry, is described and the case discussed.

Anaerobic bacteria in dentoalveolar abscesses

The present study was initiated to determine the bacteriology of 40 orofacial abscesses of dental origin in patients who had taken antibiotics for several days. Bacteria were isolated from all but 2 specimens. Aerobic or facultative anaerobic bacteria were isolated in 21 cases, obligate anaerobic bacteria in 17 cases, whereas in 11 cases, polymicrobial growth was revealed. The average number of bacterial species was 2.1 per specimen. Gram positive aerobic micro-organisms predominated, namely, Staphylococcus epidermidis followed by Streptococci (group A) and Staphylococcus aureus. Among obligate anaerobes, Gram positive micro-organisms, peptostreptococci and peptococci were more often isolated, in the following decreasing order: Ps. productus, Ps. intermedius, Ps. parvulus, Ps. anaerobius, Pc. constellatus, Pc. prevotii. Gram negative anaerobic rods were detected in a small number of cases, namely B. corrodens, B. fragilis, B. melaninogenicus, B. ochraceus, B. oralis. Quantitative determination did not show any meaningful difference between aerobic and anaerobic isolates. Susceptibility tests against a series of antibiotics showed that ampicillin was the most active in aerobes and cefoxitin in anaerobes.