1,068 research outputs found
Can private obstetric care be saved in South Africa?
This article examines the question of whether private obstetric care in South Africa (SA) can be saved in view of the escalation in medical and legal costs brought about by a dramatic increase in medical negligence litigation. This question is assessed with reference to applicable medical and legal approaches. The crux of the matter is essentially a question of affordability. From a medical perspective, it seems that the English system (as articulated by the Royal College of Obstetricians and Gynaecologists) as well as American perspectives may be well suited to the SA situation. Legal approaches are assessed in the context of the applicable medicolegal framework in SA, the present nature of damages and compensation with reference to obstetric negligence liability, as well as alternative options (no-fault and capping of damages) to the present system based on fault. It is argued, depending on constitutional considerations, that a system of damages caps for noneconomic damages seems to be the most appropriate and legally less invasive system in conjunction with the establishment of a state excess insurance fund
Cannabis legalisation and testing for cannabis use in safety- and risk-sensitive environments
The legalisation of cannabis by the High Court of South Africa, which was confirmed by the Constitutional Court, imposes challenges to occupational medical practitioners acting as medical review officers in compliance testing and fit-for-service medical examinations. The lipophilic character of the psychoactive component of cannabis, delta-9-tetrahydrocannabinol (Δ9-THC), and its prolonged elimination half-life, create challenges for the ethically and scientifically correct management of the legal use of cannabis in risk-sensitive environments. Important issues to consider in testing for cannabis use are: the stance of ‘zero tolerance’; screening and confirmation cut-off concentrations; and the bio-matrices used for testing. Constitutional rights relate to privacy, freedom, autonomy, freedom of religion and the equal enjoyment of rights and privileges, which must be balanced against the health and safety of others
Comparison Of Several Aitken Nuclei Counters
The basic thermodynamical processes leading to the formation of droplets in the central part of the Nolan-Pollak counter are analyzed in some detail. The comparison of the UMR-Absolute Aitken Nuclei counter with Nolan-Pollak, General Electric and Gardner counters showed consistently higher counts of the UMR-AAN counter. The mean deviations varied between 20% and 50% depending on the type of the counter, nuclei concentration and nature. Several observations are made on ultrafine particle counting. © 1981
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Poly(2-propylacrylic acid)/poly(lactic-co-glycolic acid) blend microparticles as a targeted antigen delivery system to direct either CD4+ or CD8+ T cell activation.
Poly(lactic-co-glycolic acid) (PLGA) based microparticles (MPs) are widely investigated for their ability to load a range of molecules with high efficiency, including antigenic proteins, and release them in a controlled manner. Micron-sized PLGA MPs are readily phagocytosed by antigen presenting cells, and localized to endosomes. Due to low pH and digestive enzymes, encapsulated protein cargo is largely degraded and processed in endosomes for MHC-II loading and presentation to CD4+ T cells, with very little antigen delivered into the cytosol, limiting MHC-I antigenic loading and presentation to CD8+ T cells. In this work, PLGA was blended with poly(2-propylacrylic acid) (PPAA), a membrane destabilizing polymer, in order to incorporate an endosomal escape strategy into PLGA MPs as an easily fabricated platform with diverse loading capabilities, as a means to enable antigen presentation to CD8+ T cells. Ovalbumin (OVA)-loaded MPs were fabricated using a water-in-oil double emulsion with a 0% (PLGA only), 3 and 10% PPAA composition. MPs were subsequently determined to have an average diameter of 1 µm, with high loading and a release profile characteristic of PLGA. Bone marrow derived dendritic cells (DCs) were then incubated with MPs in order to evaluate localization, processing, and presentation of ovalbumin. Endosomal escape of OVA was observed only in DC groups treated with PPAA/PLGA blends, which promoted high levels of activation of CD8+ OVA-specific OT-I T cells, compared to DCs treated with OVA-loaded PLGA MPs which were unable activate CD8+ T cells. In contrast, DCs treated with OVA-loaded PLGA MPs promoted OVA-specific OT-II CD4+ T cell activation, whereas PPAA incorporation into the MP blend did not permit CD4+ T cell activation. These studies demonstrate PLGA MP blends containing PPAA are able to provide an endosomal escape strategy for encapsulated protein antigen, enabling the targeted delivery of antigen for tunable presentation and activation of either CD4+ or CD8+ T cells
Characterization of sequences and mechanisms through which ISE/ISS-3 regulates FGFR2 splicing
Alternative splicing of fibroblast growth factor receptor-2 (FGFR2) mutually exclusive exons IIIb and IIIc results in highly cell-type-specific expression of functionally distinct receptors, FGFR2-IIIb and FGFR2-IIIc. We previously identified an RNA cis-element, ISE/ISS-3, that enhanced exon IIIb splicing and silenced exon IIIc splicing. Here, we have performed comprehensive mutational analysis to define critical sequence motifs within this element that independently either enhance splicing of upstream exons or repress splicing of downstream exons. Such analysis included use of a novel fluorescence-based splicing reporter assay that allowed quantitative determination of relative functional activity of ISE/ISS-3 mutants using flow cytometric analysis of live cells. We determined that specific sequences within this element that mediate splicing enhancement also mediate splicing repression, depending on their position relative to a regulated exon. Thus, factors that bind the element are likely to be coordinately involved in mediating both aspects of splicing regulation. Exon IIIc silencing is dependent upon a suboptimal branchpoint sequence containing a guanine branchpoint nucleotide. Previous studies of exon IIIc splicing in HeLa nuclear extracts demonstrated that this guanine branchsite primarily impaired the second step of splicing suggesting that ISE/ISS-3 may block exon IIIc inclusion at this step. However, results presented here that include use of newly developed in vitro splicing assays of FGFR2 using extracts from a cell line expressing FGFR2-IIIb strongly suggest that cell-type-specific silencing of exon IIIc occurs at or prior to the first step of splicing
A Comprehensive Echinacea Germplasm Collection Located at the North Central Regional Plant Introduction Station, Ames, Iowa
Echinacea is a well-established, high-value crop, both as an ornamental and dietary supplement. A comprehensive collection of Echinacea germplasm is currently held at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS) in Ames, Iowa, and is available via seed distribution for research purposes . The NCRPIS\u27s mission includes: (1) The conservation of genetically diverse crop germplasm through collection and acquisition; (2) The conduct of germplasm-related research; and (3) The encouragement of the use of the germplasm collections and associated information for research, crop improvement, and product development.
Representing all nine species collected throughout their respective North American geographic ranges, the Echinacea collect.ion includes 159 accessions (Table 1). Extensive morphological characterization data associated with t.he collection have been assembled and are available to researchers to aid in select.ion criteria. The collection has been used extensively for various research projects ranging from ornamental breeding studies for the horticulture trade to HPLC analysis of metabolites of interest to the phytopharmaceutical industry.
Germplasm is collected and made available for distribution through a series of steps. Those steps include: (1) Acquisition and exploration; (2) Regeneration and evaluation; (3) Dormancy and germination stu dies; (4) Seed propagation in field cages with pollinating insects; (5) Harvesting, drying, cleaning, and processing seeds; (6) Long-term storage under cont.rolled conditions; and (7) Distribution for research purposes
Effects of urodilatin on natriuresis in cirrhosis patients with sodium retention
BACKGROUND: Sodium retention and ascites are serious clinical problems in cirrhosis. Urodilatin (URO) is a peptide with paracrine effects in decreasing sodium reabsorption in the distal nephron. Our aim was to investigate the renal potency of synthetic URO on urine sodium excretion in cirrhosis patients with sodium retention and ascites. METHODS: Seven cirrhosis patients with diuretics-resistant sodium retention received a short-term (90 min) infusion of URO in a single-blind, placebo-controlled cross-over study. In the basal state after rehydration the patients had urine sodium excretion < 50 mmol/24 h. RESULTS: URO transiently increased urine sodium excretion from 22 ± 16 μmol/min (mean ± SD) to 78 ± 41 μmol/min (P < 0.05) and there was no effect of placebo (29 ± 14 to 44 ± 32). The increase of URO's second messenger after the receptor, cGMP, was normal. URO had no effect on urine flow or on blood pressure. Most of the patients had highly elevated plasma levels of renin, angiotensin II and aldosterone and URO did not change these. CONCLUSION: The short-term low-dose URO infusion increased the sodium excretion of the patients. The increase was small but systematic and potentially clinically important for such patients. The small response contrasts the preserved responsiveness of the URO receptors. The markedly activated systemic pressor hormones in cirrhosis evidently antagonized the local tubular effects of URO
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