Immobilization of active human carboxylesterase 1 in biomimetic silica nanoparticles

The encapsulation of proteins in biomimetic silica has recently been shown to successfully maintain enzymes in their active state. Organophosphate (OP) compounds are employed as pesticides as well as potent chemical warfare nerve agents. Because these toxicants are life threatening, we sought to generate biomimetic silicas capable of responding to OPs. Here, we present the silica encapsulation of human drug metabolism enzyme carboxylesterase 1 (hCE1) in the presence of a range of catalysts. hCE1 was successfully encapsulated into silica particles when lysozyme or the peptide R5 were used as catalysts; in contrast, polyethyleneimine (PEI), a catalyst employed to encapuslate other enzymes, did not facilitate hCE1 entrapment. hCE1 silica particles in a column chromatography format respond to the presence of the organophosphate (OP) pesticides paraoxon and dimethyl-p-nitrophenyl phosphate in solution. These results may lead to novel approaches to detect OP pesticides or other weaponized agents that bind hCE1

Establishment, optimisation and quantitation of a bioluminescent murine infection model of visceral leishmaniasis for systematic vaccine screening

Visceral leishmaniasis is an infectious parasitic disease caused by the protozoan parasites Leishmania donovani and Leishmania infantum. The drugs currently used to treat visceral leishmaniasis suffer from toxicity and the emergence of parasite resistance, and so a better solution would be the development of an effective subunit vaccine; however, no approved vaccine currently exists. The comparative testing of a large number of vaccine candidates requires a quantitative and reproducible experimental murine infection model, but the parameters that influence infection pathology have not been systematically determined. To address this, we have established an infection model using a transgenic luciferase-expressing L. donovani parasite and longitudinally quantified the infections using in vivo bioluminescent imaging within individual mice. We examined the effects of varying the infection route, the site of adjuvant formulation administration, and standardised the parasite preparation and dose. We observed that the increase in parasite load within the liver during the first few weeks of infection was directly proportional to the parasite number in the initial inoculum. Finally, we show that immunity can be induced in pre-exposed animals that have resolved an initial infection. This murine infection model provides a platform for systematic subunit vaccine testing against visceral leishmaniasis

Exploring Patients' Experiences of Internet-Based Self-Management Support for Low Back Pain in Primary Care

OBJECTIVE: We explored patients' experiences of using Internet-based self-management support for low back pain (LBP) in primary care, with and without physiotherapist telephone guidance. DESIGN: Exploratory descriptive qualitative study using thematic analysis, nested within a randomized feasibility trial. METHODS: Patients with LBP who participated in a feasibility trial of the SupportBack Internet intervention (ISRCTN: 31034004) were invited to take part in semistructured telephone interviews after the three-month intervention period (a convenience sample from within the trial population). Fifteen participants took part (age range = 36-87 years, 66.7% female, characteristics representative of the trial population). Data were analyzed thematically. RESULTS: Analysis resulted in the development of six themes (subthemes in parentheses): Perceptions of SupportBack's design (Clarity and ease of use, Variety and range of information provided, Need for specificity and flexibility), Engaging with the SupportBack intervention, Promoting positive thought processes (Reassurance, Awareness of self-management), Managing behavior with SupportBack (Motivation and goal setting, Using activity as a pain management strategy, Preferences for walking or gentle back exercises), Feeling supported by telephone physiotherapists (Provision of reassurances and clarity, Physiotherapists are motivating), Severity and comorbidity as barriers (Preexisting condition or severity acting as a barrier, Less useful for mild low back pain). CONCLUSIONS: The Internet intervention SupportBack appeared to feasibly support self-management of LBP. Reassurance and ongoing support to implement behavioral changes were central to reported benefits. The addition of physiotherapist telephone support further enhanced the patient experience and the potential utility of the intervention

The African warlord revisited

To date, warlordism in Africa has been viewed solely negatively. This has come about, in part, because of the analytical lenses that have been used. Typically, warlordism has been examined at the state level; and behavioural traits, rather than definitionally necessary components, have been the focus. In effect, ‘warlord’ has been confused with other violent actors. I suggest here a reconceptualisation ‘from below’, which takes into account variation in types of warlordism, and which allows for both positive and negative effects of warlordism on society and the state

The science of clinical practice: disease diagnosis or patient prognosis? Evidence about "what is likely to happen" should shape clinical practice.

BACKGROUND: Diagnosis is the traditional basis for decision-making in clinical practice. Evidence is often lacking about future benefits and harms of these decisions for patients diagnosed with and without disease. We propose that a model of clinical practice focused on patient prognosis and predicting the likelihood of future outcomes may be more useful. DISCUSSION: Disease diagnosis can provide crucial information for clinical decisions that influence outcome in serious acute illness. However, the central role of diagnosis in clinical practice is challenged by evidence that it does not always benefit patients and that factors other than disease are important in determining patient outcome. The concept of disease as a dichotomous 'yes' or 'no' is challenged by the frequent use of diagnostic indicators with continuous distributions, such as blood sugar, which are better understood as contributing information about the probability of a patient's future outcome. Moreover, many illnesses, such as chronic fatigue, cannot usefully be labelled from a disease-diagnosis perspective. In such cases, a prognostic model provides an alternative framework for clinical practice that extends beyond disease and diagnosis and incorporates a wide range of information to predict future patient outcomes and to guide decisions to improve them. Such information embraces non-disease factors and genetic and other biomarkers which influence outcome. SUMMARY: Patient prognosis can provide the framework for modern clinical practice to integrate information from the expanding biological, social, and clinical database for more effective and efficient care

Stable large area drop-on-demand deposition of a conductive polymer ink for 3D-printed electronics, enabled by bio-renewable co-solvents

Development of conductive polymer ink formulations with reliable jetting stability and physical properties could offer sustainable routes for scaling-up the 3D-printing of electronics. We report a new poly(3,4-ethylenedioxythiophene) polystyrene sulphonate (PEDOT:PSS) ink formulation, InkCG, using bio-renewable solvents dihydrolevoglucosenone (cyrene) and glycerol carbonate (GC) as an alternative to commonly used dimethyl sulfoxide (DMSO). These green organic co-solvents enhance jetting reliability and long-term stability of the ink and improve electrical properties of the deposited PEDOT:PSS layers, compared to the commonly used DMSO-containing ink formulations. We achieve large-area and high-fidelity electronic devices (array of 140 devices) with reproducible electrical performance through inkjet-based 3D printing. Enhanced performance stability is observed under cyclic bending, thermal annealing, UV or IR exposure, offering exciting opportunities for sustainable deposition of PEDOT:PSS for large-area 3D printing and its exploitation in heterostructures and flexible electronics

Seasonal and species‐level water‐use strategies and groundwater dependence in dryland riparian woodlands during extreme drought

Drought‐induced groundwater decline and warming associated with climate change are primary threats to dryland riparian woodlands. We used the extreme 2012–2019 drought in southern California as a natural experiment to assess how differences in water‐use strategies and groundwater dependence may influence the drought susceptibility of dryland riparian tree species with overlapping distributions. We analyzed tree‐ring stable carbon and oxygen isotopes collected from two cottonwood species (Populus trichocarpa and P. fremontii) along the semi‐arid Santa Clara River. We also modeled tree source water δ18O composition to compare with observed source water δ18O within the floodplain to infer patterns of groundwater reliance. Our results suggest that both species functioned as facultative phreatophytes that used shallow soil moisture when available but ultimately relied on groundwater to maintain physiological function during drought. We also observed apparent species differences in water‐use strategies and groundwater dependence related to their regional distributions. P. fremontii was constrained to more arid river segments and ostensibly used a greater proportion of groundwater to satisfy higher evaporative demand. P. fremontii maintained ∆13C at pre‐drought levels up until the peak of the drought, when trees experienced a precipitous decline in ∆13C. This response pattern suggests that trees prioritized maintaining photosynthetic processes over hydraulic safety, until a critical point. In contrast, P. trichocarpa showed a more gradual and sustained reduction in ∆13C, indicating that drought conditions induced stomatal closure and higher water use efficiency. This strategy may confer drought avoidance for P. trichocarpa while increasing its susceptibility to anticipated climate warming