108 research outputs found
Early prediction of hypoxic ischaemic encephalopathy in newborn infants in a resource-limited setting
Includes bibliographical references.Hypoxic ischaemic encephalopathy (HIE) after birth is an important cause of neonatal morbidity and mortality, particularly in resource-limited regions. Therapeutic hypothermia initiated within the first 6 hours of life, in settings that can offer neonatal intensive care, is a therapy that can reduce death or severe disability in newborn infants with moderate or severe HIE. Therapeutic hypothermia has not been shown to be safe or effective in low-resource settings where neonatal intensive care is not available; however, there are situations such as in some centres in South Africa, where limited neonatal intensive care (NICU) is available against a background of moderate neonatal mortality rates, relatively low socio-economic conditions and limited capacity for long-term follow-up. In such settings, accurate case definition and early prediction of HIE and outcome may assist with the appropriate allocation of resources. The amplitude-integrated electro-encephalogram (aEEG) is an ideal tool to use for prediction of outcome and the need for cooling, but it’s availability is limited, particularly at primary and secondary hospitals
Newborns should be receiving premedication before elective intubation
BACKGROUND: Intubation is a common neonatal procedure. Premedication is accepted as a standard of care, but its use is not universal and wide variations exist in practice. OBJECTIVE: To evaluate current practices for premedication use prior to elective neonatal intubation in South Africa (SA). METHOD: We invited 481 clinicians to participate in a cross-sectional web-based survey. RESULTS: We received responses from 28.3% of the clinicians surveyed; 54.1% were from the private sector and 45.9% from the state sector. Most respondents worked in medium-sized neonatal units with six to ten beds. Most paediatricians (76.0%) worked in the private sector, and 78.6% of neonatologists in the state sector. Premedication was practised by 71.9% of the respondents, but only 38.5% of neonatal units had a written policy. Sedatives were used for premedication by 63.2% of the respondents. Midazolam (41.5%), morphine (34.0%) and ketamine (20.8%) were most commonly used. Muscle relaxants and atropine were not routinely administered. Suxamethonium was the muscle relaxant of choice. Varied combinations of agents or single agents were used. Midazolam used alone was the preferred option. CONCLUSION: This first survey of premedication for neonatal intubation in SA revealed variations in practice, with a minority of clinicians following a written policy. The findings can be used to benchmark practice and inform the design of local collaborative trials aimed at determining optimal premedication prior to neonatal intubation. The survey demonstrates clinicians' reluctance to participate in surveys, suggesting a need for a national collaborative network to obtain representative data
Newborns should be receiving premedication before elective intubation
Background. Intubation is a common neonatal procedure. Premedication is accepted as a standard of care, but its use is not universal and wide variations exist in practice.Objective. To evaluate current practices for premedication use prior to elective neonatal intubation in South Africa (SA).Method. We invited 481 clinicians to participate in a cross-sectional web-based survey.Results. We received responses from 28.3% of the clinicians surveyed; 54.1% were from the private sector and 45.9% from the state sector. Most respondents worked in medium-sized neonatal units with six to ten beds. Most paediatricians (76.0%) worked in the private sector, and 78.6% of neonatologists in the state sector. Premedication was practised by 71.9% of the respondents, but only 38.5% of neonatal units had a written policy. Sedatives were used for premedication by 63.2% of the respondents. Midazolam (41.5%), morphine (34.0%) and ketamine (20.8%) were most commonly used. Muscle relaxants and atropine were not routinely administered. Suxamethonium was the muscle relaxant of choice. Varied combinations of agents or single agents were used. Midazolam used alone was the preferred option.Conclusion. This first survey of premedication for neonatal intubation in SA revealed variations in practice, with a minority of clinicians following a written policy. The findings can be used to benchmark practice and inform the design of local collaborative trials aimed at determining optimal premedication prior to neonatal intubation. The survey demonstrates clinicians’ reluctance to participate in surveys, suggesting a need for a national collaborative network to obtain representative data
Anti-trypanosomal 8-hydroxyl naphthyridines are chelators of divalent transition metals
The lack of information regarding the mechanisms of action (MoA) or specific molecular targets of phenotypically active compounds can prove a barrier to their development as chemotherapeutic agents. Here, we report the results of our orthogonal genetic, molecular, and biochemical studies to determine the MoA of a novel 7-substituted 8-hydroxy-1,6-naphthyridine (8-HNT) series that displays promising activity against
Trypanosoma brucei
and
Leishmania donovani
.
</jats:p
Pharmacological validation of N-myristoyltransferase as a drug target in <i>Leishmania donovani</i>
Visceral leishmaniasis (VL), caused by the protozoan parasites Leishmania donovani and L. infantum, is responsible for ~30,000 deaths annually. Available treatments are inadequate and there is a pressing need for new therapeutics. N-Myristoyltransferase (NMT) remains one of the few genetically validated drug targets in these parasites. Here, we sought to pharmacologically validate this enzyme in Leishmania. A focused set of 1,600 pyrazolyl sulfonamide compounds was screened against L. major NMT in a robust high-throughput biochemical assay. Several potent inhibitors were identified with marginal selectivity over the human enzyme. There was little correlation between the enzyme potency of these inhibitors and their cellular activity against L. donovani axenic amastigotes and this discrepancy could be due to poor cellular uptake due to the basicity of these compounds. Thus, a series of analogues were synthesised with less basic centres. Although most of these compounds continued to suffer from relatively poor anti-leishmanial activity, our most potent inhibitor of LmNMT (DDD100097, Ki 0.34 nM), showed modest activity against L. donovani intracellular amastigotes (EC50 2.4 µM) and maintained a modest therapeutic window over the human enzyme. Two un-biased approaches, namely screening against our cosmid-based overexpression library and thermal proteome profiling (TPP), confirm that DDD100097 (compound 2) acts on-target within parasites. Oral dosing with compound 2 resulted in a 52% reduction in parasite burden in our mouse model of VL. Thus, NMT is now a pharmacologically validated target in Leishmania. The challenge in finding drug candidates remains to identify alternative strategies to address the drop-off in activity between enzyme inhibition and in vitro activity while maintaining sufficient selectivity over the human enzyme, both issues that continue to plague studies in this area
Recommended from our members
Cost-utility of revisions for cervical deformity correction warrants minimization of reoperations.
Background: Cervical deformity (CD) surgery has become increasingly more common and complex, which has also led to reoperations for complications such as distal junctional kyphosis (DJK). Cost-utility analysis has yet to be used to analyze CD revision surgery in relation to the cost-utility of primary CD surgeries. The aim of this study was to determine the cost-utility of revision surgery for CD correction.
Methods: Retrospective review of a multicenter prospective CD database. CD was defined as at least one of the following: C2-C7 Cobb \u3e10°, cervical lordosis (CL) \u3e10°, cervical sagittal vertical axis (cSVA) \u3e4 cm, chin-brow vertical angle (CBVA) \u3e25°. Quality-adjusted life year (QALY) were calculated by EuroQol Five-Dimensions questionnaire (EQ-5D) and Neck Disability Index (NDI) mapped to SF-6D index and utilized a 3% discount rate to account for residual decline to life expectancy (men: 76.9 years, women: 81.6 years). Medicare reimbursement at 30 days assigned costs for index procedures (9+ level posterior fusion, 4-8 level posterior fusion with anterior fusion, 2-3 level posterior fusion with anterior fusion, 4-8 level anterior fusion) and revision fusions (2-3 level, 4-8 level, or 9+ level posterior refusion). Cost per QALY gained was calculated.
Results: Eighty-nine CD patients were included (61.6 years, 65.2% female). CD correction for these patients involved a mean 7.7±3.7 levels fused, with 34% combined approach surgeries, 49% posterior-only and 17% anterior-only, 19.1% three-column osteotomy. Costs for index surgeries ranged from 44,318 and cost per QALY of 41,510. Indications for revisions were DJK (5/11), neurologic impairment [4], infection [1], prominent/painful instrumentation [1]. Average QALYs gained was 1.62 per revision patient. Cost was 28,138 per QALY, in addition to the $27,267 per QALY for primary CD surgeries. For primary CD patients, CD surgery has the potential to be cost effective, with the caveats that a patient livelihood extends long enough to have the benefits and durability of the surgery is maintained. Efforts in research and surgical technique development should emphasize minimization of reoperation causes just as DJK that significantly affect cost utility of these surgeries to bring cost-utility to an acceptable range
Affected Experiencers
Numerous languages permit an NP that is not selected by the verb to be added to a clause, with several different possible interpretations. We divide such non-selected arguments into possessor, benefactive, attitude holder, and affected experiencer categories, on the basis of syntactic and semantic differences between them. We propose a formal analysis of the affected experiencer construction. In our account, a syntactic head Aff(ect) introduces the experiencer argument, and adds a conventional implicature to the effect that any event of the type denoted by its syntactic sister is the source of the experiencer’s psychological experience. Hence, our proposal involves two tiers of meaning: the at-issue meaning of the sentence, and some not-at-issue meaning (an implicature). A syntactic head can introduce material on both tiers. Additionally, we allow two parameters of variation: (i) the height of the attachment of Aff, and (ii) how much of the semantics is at-issue and how much is an implicature. We show that these two parameters account for the attested variation across our sample of languages, as well as the significant commonalities among them. Our analysis also accounts for significant differences between affected experiencers and the other types of non-selected arguments, and we also note a generalization to the effect that purely not-at-issue non-selected arguments can only be weak or clitic pronouns
Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants
This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing
Software for the frontiers of quantum chemistry:An overview of developments in the Q-Chem 5 package
This article summarizes technical advances contained in the fifth major release of the Q-Chem quantum chemistry program package, covering developments since 2015. A comprehensive library of exchange–correlation functionals, along with a suite of correlated many-body methods, continues to be a hallmark of the Q-Chem software. The many-body methods include novel variants of both coupled-cluster and configuration-interaction approaches along with methods based on the algebraic diagrammatic construction and variational reduced density-matrix methods. Methods highlighted in Q-Chem 5 include a suite of tools for modeling core-level spectroscopy, methods for describing metastable resonances, methods for computing vibronic spectra, the nuclear–electronic orbital method, and several different energy decomposition analysis techniques. High-performance capabilities including multithreaded parallelism and support for calculations on graphics processing units are described. Q-Chem boasts a community of well over 100 active academic developers, and the continuing evolution of the software is supported by an “open teamware” model and an increasingly modular design
- …