The considerations, experiences and support needs of family members making treatment decisions for patients admitted with major stroke: a qualitative study

Background

Treatment decision-making by family members on behalf of patients with major stroke can be challenging because of the shock of the diagnosis and lack of knowledge of the patient’s treatment preferences. We aimed to understand how, and why, family members made certain treatment decisions, and explored their information and support needs.

Method

Semi-structured interviews with family members (n = 24) of patients with major stroke, within 2 weeks of hospital admission. Data were analysed thematically.

Results

Families’ approach to treatment decision-making lay on a spectrum according to the patient’s state of health pre-stroke (i.e. patient’s prior experience of illness and functional status) and any views expressed about treatment preferences in the event of life-threatening illness. Support and information needs varied according to where they were on this spectrum. At one extreme, family members described deciding not to initiate life-extending treatments from the outset because of the patients’ deteriorating health and preferences expressed pre-stroke. Information from doctors about poor prognosis was merely used to confirm this decision. In the middle of the spectrum were family members of patients who had been moderately independent pre-stroke. They described the initial shock of the diagnosis and how they had initially wanted all treatments to continue. However, once they overcame their shock, and had gathered relevant information, including information about poor prognosis from doctors, they decided that life-extending treatments were no longer appropriate. Many reported this process to be upsetting and expressed a need for psychological support. At the other end of the spectrum were family members of previously independent patients whose preferences pre-stroke had not been known. Family members described feeling extremely distressed at such an unexpected situation and wanting all treatments to continue. They described needing psychological support and hope that the patient would survive.

Conclusion

The knowledge that family members’ treatment decision-making approaches lay on a spectrum depending on the patient’s state of health and stated preferences pre-stroke may allow doctors to better prepare for discussions regarding the patient’s prognosis. This may enable doctors to provide information and support that is tailored towards family members’ needs.

Postnatal Development of Spasticity Following Transgene Insertion in the Mouse βIV Spectrin Gene (SPTBN4)

BACKGROUND

The L25 mouse line was generated by random genomic insertion of a lens-specific transgene. Inbreeding of L25 hemizygotes revealed an unanticipated spastic phenotype in the hind limbs.

OBJECTIVE

The goals were to characterize the motor phenotype in the L25 mice and to map the transgene insert site within the mouse genome.

METHODS

Six pairs of L25+/- mice were repeatedly mated. Beginning at weaning, all progeny were inspected for body weight and motor signs twice weekly until they displayed predefined ethical criteria for termination. The transgene insert site was determined by whole genome sequencing. Western blotting was used to compare the expression levels of beta-IV spectrin protein in the brain.

RESULTS

Matings of hemizygous L25+/- × L25+/- mice yielded 20% (29/148) affected weanlings, identified by an abnormal retraction of the hind limbs when lifted by the tail, and a fine tremor. Affected mice were less mobile and grew more slowly than wild-type littermates. All affected mice required termination due to >15% loss of body weight (50% survival age 92 days). At the endpoint, mice showed varying degrees of spastic paresis or spastic paralysis localised to the hind limbs. Motor endplates remained fully innervated. Genome sequencing confirmed that the transgene was inserted in the locus of βIV spectrin of L25 mice. Western blotting indicated that this random insertion had greatly reduced the expression of βIV spectrin protein in the affected L25 mice.

CONCLUSIONS

The results confirm the importance of βIV spectrin for maintaining central motor pathway control of the hind limbs, and provide a developmental time course for the phenotype.

The neuromuscular junction: measuring synapse size, fragmentation and changes in synaptic protein density using confocal fluorescence microscopy

The neuromuscular junction (NMJ) is the large, cholinergic relay synapse through which mammalian motor neurons control voluntary muscle contraction. Structural changes at the NMJ can result in neurotransmission failure, resulting in weakness, atrophy and even death of the muscle fiber. Many studies have investigated how genetic modifications or disease can alter the structure of the mouse NMJ. Unfortunately, it can be difficult to directly compare findings from these studies because they often employed different parameters and analytical methods. Three protocols are described here. The first uses maximum intensity projection confocal images to measure the area of acetylcholine receptor (AChR)-rich postsynaptic membrane domains at the endplate and the area of synaptic vesicle staining in the overlying presynaptic nerve terminal. The second protocol compares the relative intensities of immunostaining for synaptic proteins in the postsynaptic membrane. The third protocol uses Fluorescence Resonance Energy Transfer (FRET) to detect changes in the packing of postsynaptic AChRs at the endplate. The protocols have been developed and refined over a series of studies. Factors that influence the quality and consistency of results are discussed and normative data are provided for NMJs in healthy young adult mice.

Smartphone apps in microbiology--is better regulation required?

Increasing diversity of available medical applications (apps) has led to their widespread use in healthcare delivery. However, app involvement in diagnosis and patient management has raised concerns, specifically regarding accuracy and reliability of content. Here, we report on the contemporary range of microbiology-themed apps and prevalence of medical professional involvement in app development. Of 94 microbiology-themed apps identified, only 34% had stated medical professional involvement. The lack of such involvement in app design is concerning and undermines consumers' ability to be informed regarding quality of content. We propose that increased regulatory measures are introduced to safeguard patient welfare.

Effect of the small molecule plasminogen activator inhibitor-1 (PAI-1) inhibitor, PAI-749, in clinical models of fibrinolysis

BACKGROUND

The principal inhibitor of fibrinolysis in vivo is plasminogen activator inhibitor-1 (PAI-1). PAI-749 is a small molecule inhibitor of PAI-1 with proven antithrombotic efficacy in several preclinical models.

OBJECTIVE

To assess the effect of PAI-749, by using an established ex vivo clinical model of thrombosis and a range of complementary in vitro human plasma-based and whole blood-based models of fibrinolysis.

METHODS

In a double-blind, randomized, crossover study, ex vivo thrombus formation was assessed using the Badimon chamber in 12 healthy volunteers during extracorporeal administration of tissue-type plasminogen activator (t-PA) in the presence of PAI-749 or control. t-PA-mediated lysis of plasma clots and of whole blood model thrombi were assessed in vitro. The role of vitronectin was examined by assessing lysis of fibrin clots generated from purified plasma proteins.

RESULTS

There was a dose-dependent reduction in ex vivo thrombus formation by t-PA (P < 0.0001). PAI-749 had no effect on in vitro or ex vivo thrombus formation or fibrinolysis in the presence or absence of t-PA. Inhibition of PAI-1 with a blocking antibody enhanced fibrinolysis in vitro (P < 0.05).

CONCLUSIONS

Despite its efficacy in a purified human system and in preclinical models of thrombosis, the current study suggests that PAI-749 does not affect thrombus formation or fibrinolysis in a range of established human plasma and whole blood-based systems.

Substrate specificity and kinetic mechanism of human placental insulin receptor/kinase

The insulin receptor has been shown to be a protein kinase which phosphorylates its substrates on tyrosine residues. To examine the acceptor specificity of affinity-purified insulin receptor/kinase, hydroxyamino acid containing analogues of the synthetic peptide substrate Arg-Arg-Leu-Ile-Glu-Asp-Ala-Glu-Tyr-Ala-Ala-Arg-Gly were prepared. Substitution of serine, threonine, or D-tyrosine for L-tyrosine completely ablated the acceptor activity of the synthetic peptides. These peptides, along with a phenylalanine-containing analogue, did serve as competitive inhibitors of the insulin receptor/kinase with apparent Ki values in the range of 2-4 mM. These data suggest that the insulin receptor/kinase is specific for tyrosine residues in its acceptor substrate and imply that serine phosphate or threonine phosphate present in receptor is due to phosphorylation by other protein kinases. The kinetics of the phosphorylation of the L-tyrosine-containing peptide were examined by using prephosphorylated insulin receptor/kinase. Prephosphorylation of the receptor was necessary to maximally activate the kinase and to linearize the initial velocity of the peptide phosphorylation reaction. The data obtained rule out a ping-pong mechanism and are consistent with a random-order rapid-equilibrium mechanism for the phosphorylation of this peptide substrate. Additional experiments demonstrated that the autophosphorylated insulin receptor was not able to transfer the preincorporated phosphate to the synthetic peptide substrate. Thus, the insulin receptor/kinase catalyzes the reaction via a mechanism that does not involve transfer of phosphate from a phosphotyrosine-containing enzyme intermediate.

Effect of high-fat diet on cholesterol distribution in plasma lipoproteins, cholesterol esterifying activity in leucocytes, and erythrocyte membrane components studied: importance of body weight

Effects of isocaloric changes in dietary fat on plasma lipoproteins and lipids and enzymes of erythrocytes and leucocytes were assessed. Subjects with a higher Brocca index showed increase in total and LDL cholesterol, significant reduction in HDL cholesterol, and increased total cholesterol:HDL cholesterol ratio after high-fat diet consumption. Due to high-fat diet feeding, erythrocyte membrane and leucocyte cholesterol and phospholipid contents were increased, cholesterol:phospholipid molar ratio was elevated, and erythrocyte enzymes (G6PD and 6PGD) and leucocyte enzymes (CEH and CES) were elevated. Erythrocyte membrane glycoprotein components showed marked increase, indicating possible alterations of membrane surfaces. The metabolic alterations were reversed slowly after resumption of the normal (low-fat) diet. Body weight plays an important role in the alterations in major lipoprotein cholesterol contents in response to changes in dietary fat composition. Cellular changes indicate alterations in structure and function of blood cells due to high-fat diet feeding.

Ferric acetate-uranium acetate reagent in cholesterol estimations in plasma and high density lipoprotein fractions: comparison with existing methods

The use of ferric acetate-uranium acetate colour reaction for the estimation of cholesterol in the supernatants of plasma samples after precipitation of low density lipoprotein (LDL) and very low density lipoprotein (VLDL) cholesterol by heparin-MnCl2 was assessed and compared with the conventional method using the FeCl3 colour reaction and also with the method using o-phthalaldehyde as the colouring reagent. All three methods gave comparable values when total cholesterol in plasma samples was determined and also when high density lipoprotein (HDL) fractions were separated by ultracentrifugation and the cholesterol contents determined. But when heparin-MnCl2 precipitation was used for HDL separation, and the cholesterol content determined, the FeCl3 method gave significantly lower values. This could be due to interference of the cholesterol colour reaction with FeCl3, due to Mn2+ ions present in the supernatant. Addition of Mn2+ to cholesterol standards and subsequent colour development with ferric acetate-uranium acetate and FeCl3 reagents showed that Mn2+ decreased the absorbancy of the coloured complex at 560 nm only when FeCl3 was used. Percentage recovery of added cholesterol was also lower when the heparin-MnCl2 supernatant was treated with FeCl3 reagent for colour development. Use of ferric acetate-uranium acetate reagent provides a simpler and quicker method. It does not suffer from interference due to the presence of Mn2+ ions and gives results comparable to the o-phthalaldehyde method and those using ultracentrifugation as the separation procedure.

Effect of iodobenzene therapy on mitochondrial activity in 2-thiouracil-induced hypothyroidism in weanling rats

Hypothyroidism was produced in weanling albino rats by the oral administration of 2-thiouracil (TU) for 110 days. These animals recorded nearly 50 per cent reduction in mitochondrial oxidation of succinate, protein content and the activity of inner mitochondrial membrane-bound beta-hydroxybutyrate dehydrogenase. Administration of iodobenzene (IB; 0.1 microgram/rat/day) and L-thyroxine (T4; 0.6 microgram/rat/day) to two sets of hypothyroid rats restored the reduced oxidation rate, enzyme activity and protein content to near normal values. IB was comparable to T4 and may act as a thyroid stimulant.