1
|
Burgess AJ, Clee D, Prichburg A, Burberry DJ, Keen L, Davies EA. CWTCH in the community: improving education to reduce adverse outcomes for patients who fall in nursing homes. Gerontol Geriatr Educ 2023:1-9. [PMID: 37667556 DOI: 10.1080/02701960.2023.2255536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Falls in nursing homes (NH) are common and cause significant morbidity and mortality. We proposed that by improving staff education, the volume of emergency calls, hospital conveyance and adverse patient outcomes could be reduced. An analysis of the volume of emergency calls coded as Falls from January 2020 to February 2022, with 4907 calls in total, 866 were falls (17.65%), further 1032 potential falls (21.07%). A survey was sent to NH to evaluate how staff treated residents who fell and showed that 47% of NH do not have any guidelines for falls and emergency services, are contacted 88.24% of the time. Education was delivered focusing on the negative consequences of falls. The package used the acronym "CWTCH" translated from the Welsh language as a hug. Education was offered to all NH (177 staff) and Feedback showed 100% felt more confident and found the session helpful with 90.96% less likely to contact emergency services. Falls remain a significant burden on emergency services, with clear opportunity to improve patient outcomes and experience. A referral pathway was developed diverting calls, showing a significant change in conveyance to hospital (p < 0.05).
Collapse
Affiliation(s)
- Alexandra Jayne Burgess
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
- Swansea University, Swansea, Wales, UK
| | - Debra Clee
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
| | - Alice Prichburg
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
| | - David James Burberry
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
| | - Leigh Keen
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
| | - Elizabeth Alexandra Davies
- Older Person's Assessment Service (OPAS), Morriston Hospital, Swansea Bay University Health Board (SBUHB), Swansea, UK
- Swansea University, Swansea, Wales, UK
| |
Collapse
|
2
|
McMillan M, Burgess AJ. Prescribe, Review, Now!: an assessment of adequate PRN analgesia and associated laxative prescribing using Hospital Electronic Prescribing and Medicines Administration (HEPMA). BMJ Open Qual 2023; 12:bmjoq-2022-002090. [PMID: 36813470 PMCID: PMC9950910 DOI: 10.1136/bmjoq-2022-002090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/31/2023] [Indexed: 02/24/2023] Open
Abstract
INTRODUCTION On HEPMA there is no way to notify a prescriber if patients are regularly accessing PRN (as-required) analgesia. We aimed to assess how well PRN analgesia use is identified, the WHO analgesic ladder and whether laxatives were prescribed with opioid analgesia. METHODS 3 data collection cycles were carried out for all medical inpatients between February-April 2022. Medication was reviewed to determine: 1) PRN analgesia prescribed? 2) Is the patient accessing it >3 times in 24hours? 3) Con-current laxatives prescribed. Between each cycle, an intervention was implemented. Intervention 1: Posters were placed on each ward and circulated electronically as a cue to a review and change analgesia "Prescribe. REVIEW Now!" Intervention 2: A presentation on data, the WHO analgesic ladder and laxative prescribing was created, and circulated. RESULTS See Figure 1 - Comparison of prescribing per cycle. Cycle 1 - 167 inpatients surveyed, 58%female, 42%male, mean age 78(±13.4). Cycle 2 - 159 inpatients,65% female, 35% male, mean age of 77 (±15.7). Cycle 3 - 157 inpatients, 62% female, 38% male, mean age 78 (±15.7). Adequate prescriptions on HEPMA improved by a total of 31% (p<0.005), over 3 cycles and 2 interventions. CONCLUSIONS After each intervention there was a significant statistical improvement in prescribing analgesia and laxatives. However, there is still room for further improvement, especially in ensuring adequate laxative cover is prescribed for all patients either >65 years old, or those on opioid-based analgesia. Visual reminders on wards of regularly checking PRN medication showed to be an effective intervention.
Collapse
Affiliation(s)
- Matthew McMillan
- Morriston Hospital, Swansea Bay University Health Board, Port Talbot, UK
| | | |
Collapse
|
3
|
Burgess AJ, Clee D, Davies EA, Burberry DJ, Keen L. 1193 CWTCH IN THE COMMUNITY - IMPROVING EDUCATION TO REDUCE ADVERSE OUTCOMES FOR PATIENTS WHO FALL IN NURSING HOMES (NH). Age Ageing 2023. [DOI: 10.1093/ageing/afac322.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Abstract
Introduction
Falls have significant morbidity and mortality in Nursing Home (NH) residents. By improving education to NH staff we aim to reduce 999 calls and associated adverse outcomes. NH residents are more likely to fall than people living in the community and are more at risk of further falls as interventions and risk factor modification is more difficult.
Methods
Phase 1 - Ambulance calls, where a vehicle attended the scene, between 01/01/2020-28/02/2022 from NH in Swansea Bay University Health Board (SBUHB) concerning Falls/?Falls (Haemorrhage/lacerations, Unconscious/fainting, traumatic injuries, sick person, convulsions/fitting) were analysed and survey was sent out to all NH.
Phase 2 - Education was provided about CWTCH (hug in Welsh) and staff were surveyed post intervention. Can you move them, Will it harm them? - new neck/back pain, anticoagulation, Treat them – analgesia, wound-care, Cup of Tea – can eat and drink, Help – when contact 999.
Results
Phase 1 - Between 01/01/2020-28/02/2022, of 4907 calls, 866 were falls (17.65%) and 1032 ?Falls (21.07%), 60.49% conveyed to hospital. 47% of NH do not have falls guidelines and 100% patients are Nil by Mouth and 88.24% are not moved. Emergency services were contacted 88.24%. Phase 2 - Education was delivered to all NH in Swansea (122 staff). Feedback showed 100% feel more confident in giving food and drink, moving patients, with 90.98% less likely to contact 999 and 75.40% not having previous training with 96.72 % more confident in giving analgesia.
Conclusions
Falls remain a significant burden and a rapid service would improve care with conveyance reduction to 53.1% post education (60.55% pre-education). Future directions include offering this education to NH in Neath/Port Talbot. From March 2022, we offer same-day assessment for NH residents (and others) from primary care and ambulances and are developing a PRN analgesia pathway e.g. PENTHROX.
Collapse
Affiliation(s)
- A J Burgess
- Swansea Bay University Health Board (SBUHB) Older Person’s Assessment Service (OPAS), Morriston Hospital,
| | - D Clee
- Swansea Bay University Health Board (SBUHB) Older Person’s Assessment Service (OPAS), Morriston Hospital,
| | - E A Davies
- Swansea Bay University Health Board (SBUHB) Older Person’s Assessment Service (OPAS), Morriston Hospital,
| | - D J Burberry
- Swansea Bay University Health Board (SBUHB) Older Person’s Assessment Service (OPAS), Morriston Hospital,
| | - L Keen
- Welsh Ambulance Service NHS Trust (WAST)
| |
Collapse
|
4
|
Edgar IA, Thompson CJ, Hunter S, Burgess AJ, Lambert AW. Does the method of aeromedical evacuation from the point of wounding to a field hospital have an effect on subsequent blood product usage and patient physiology? J R Nav Med Serv 2014; 100:12-17. [PMID: 24881421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
|
5
|
Burgess AJ, Pavey S, Warrener R, Hunter LJ, Piva TJ, Musgrove EA, Saunders N, Parsons PG, Gabrielli BG. Up-regulation of p21(WAF1/CIP1) by histone deacetylase inhibitors reduces their cytotoxicity. Mol Pharmacol 2001; 60:828-37. [PMID: 11562446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
Histone deacetylase inhibitors show promise as chemotherapeutic agents and have been demonstrated to block proliferation in a wide range of tumor cell lines. Much of this antiproliferative effect has been ascribed to the up-regulated expression of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1). In this article, we report that p21 expression was up-regulated by relatively low doses of the histone deacetylase inhibitor azelaic bishydroxamic acid (ABHA) and correlated with a proliferative arrest. Higher doses of ABHA were cytotoxic. Cells that did not up-regulate p21 expression were hypersensitive to killing by ABHA and died via apoptosis, whereas up-regulation of p21 correlated with reduced sensitivity and a block in the apoptotic mechanism, and these cells seemed to die by necrosis. Using isogenic p21(+/+) and p21(-/-) cell lines and direct inhibition of caspase activity, we demonstrate that the reduced sensitivity to killing by ABHA is a consequence of inhibition of apoptosis by up-regulated p21 expression. These data indicate the enormous potential of therapeutic strategies that bypass the cytoprotective effect of p21 and act on the same molecular targets as the histone deacetylase inhibitors.
Collapse
Affiliation(s)
- A J Burgess
- Joint Experimental Oncology Program, Department of Pathology, University of Queensland, Brisbane, Queensland, Australia
| | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Brinkmann H, Dahler AL, Popa C, Serewko MM, Parsons PG, Gabrielli BG, Burgess AJ, Saunders NA. Histone hyperacetylation induced by histone deacetylase inhibitors is not sufficient to cause growth inhibition in human dermal fibroblasts. J Biol Chem 2001; 276:22491-9. [PMID: 11304533 DOI: 10.1074/jbc.m100206200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Use of specific histone deacetylase inhibitors has revealed critical roles for the histone deacetylases (HDAC) in controlling proliferation. Although many studies have correlated the function of HDAC inhibitors with the hyperacetylation of histones, few studies have specifically addressed whether the accumulation of acetylated histones, caused by HDAC inhibitor treatment, is responsible for growth inhibition. In the present study we show that HDAC inhibitors cause growth inhibition in normal and transformed keratinocytes but not in normal dermal fibroblasts. This was despite the observation that the HDAC inhibitor, suberic bishydroxamate (SBHA), caused a kinetically similar accumulation of hyperacetylated histones. This cell type-specific response to SBHA was not due to the inactivation of SBHA by fibroblasts, nor was it due to differences in the expression of specific HDAC family members. Remarkably, overexpression of HDACs 1, 4, and 6 in normal human fibroblasts resulted in cells that could be growth-inhibited by SBHA. These data suggest that, although histone acetylation is a major target for HDAC inhibitors, the accumulation of hyperacetylated histones is not sufficient to cause growth inhibition in all cell types. This suggests that growth inhibition, caused by HDAC inhibitors, may be the culmination of histone hyperacetylation acting in concert with other growth regulatory pathways.
Collapse
Affiliation(s)
- H Brinkmann
- Epithelial Pathobiology Group, Centre For Immunology and Cancer Research, University of Queensland Department of Medicine, Princess Alexandra Hospital, Brisbane, Queensland 4102, Australia
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Khan KN, Skepper JN, Hockaday AR, Burgess AJ, Huang CL. Loop diuretics inhibit detubulation and vacuolation in amphibian muscle fibres exposed to osmotic shock. J Muscle Res Cell Motil 2000; 21:79-90. [PMID: 10813637 DOI: 10.1023/a:1005618720122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The effect of loop diuretics at concentrations known to influence cellular water entry coupled to Na-K-Cl co-transport, upon the vacuolation and detubulation following osmotic shock, was investigated in amphibian skeletal muscles. These were exposed to a glycerol-Ringer solution (18 min), an isotonic Ca2+/Mg2+ Ringer solution and cooling. Adding bumetanide (1.0 and 2.0 microM) to these solutions sharply reduced the incidence of detubulation, assessed by abolition or otherwise of action potential after-depolarisations, from 93.9 +/- 4.7% (n = 6) to 5.0 +/- 1.1% (n = 4: mean +/- SEM: 2.0 microM bumetanide). It dramatically reduced the number and fraction of muscle volume occupied by tubular vacuoles, measured using confocal microscopy, from 60.3 +/- 4.3% (n = 10) to 9.0 +/- 1.1% (n = 35). The incidence of large horseradish peroxidase-lined tubular vacuoles, viewed using electronmicroscopy, similarly was reduced with 2 microM bumetanide in the glycerol-Ringer solution. Bumetanide acted through cellular volume adjustments early in the detubulation protocol. Thus, it exerted its maximum effect when added to the glycerol-Ringer, rather than the Ca2+/Mg2+ Ringer solution. Furthermore, whereas fibre diameters measured using scanning electron microscopy returned to normal during glycerol treatment relative to those of control fibres left in isotonic Ringer, addition of 2.0 microM bumetanide in the glycerol Ringer left markedly smaller fibre diameters. Finally equipotent concentrations of the chemically distinct loop diuretics. furosemide and ethacrynic acid similarly influenced detubulation. These findings implicate Na-K-Cl co-transport in the water entry into muscle fibres that would be expected following introduction of extracellular glycerol. This might then enable the subsequent Na-K-ATPase dependent water extrusion that produces the tubular distension (vacuolation) and detachment (detubulation) following glycerol withdrawal, phenomena also observed in muscular dystrophy.
Collapse
MESH Headings
- Action Potentials/drug effects
- Action Potentials/physiology
- Animals
- Bumetanide/pharmacology
- Carrier Proteins/drug effects
- Carrier Proteins/metabolism
- Cell Size/drug effects
- Cell Size/physiology
- Cryoprotective Agents/pharmacology
- Diuretics/pharmacology
- Electrophysiology
- Ethacrynic Acid/pharmacology
- Extracellular Space/metabolism
- Furosemide/pharmacology
- Glycerol/pharmacology
- In Vitro Techniques
- Intracellular Membranes/drug effects
- Intracellular Membranes/metabolism
- Intracellular Membranes/ultrastructure
- Loop of Henle/drug effects
- Loop of Henle/metabolism
- Microscopy, Confocal
- Microscopy, Electron
- Microscopy, Electron, Scanning
- Microtubules/drug effects
- Microtubules/metabolism
- Microtubules/ultrastructure
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/ultrastructure
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/ultrastructure
- Osmotic Pressure/drug effects
- Ranidae
- Sodium-Potassium-Chloride Symporters
- Vacuoles/drug effects
- Vacuoles/metabolism
- Vacuoles/ultrastructure
Collapse
Affiliation(s)
- K N Khan
- Phyisiogical Laboratory, Cambridge UK
| | | | | | | | | |
Collapse
|
8
|
Grimes EA, Burgess AJ, East JM, Lee AG. Reconstitution experiments provide no evidence for a role for the 53-kDa glycoprotein in coupling Ca2+ transport to ATP hydrolysis by the (Ca(2+)-Mg2+)-ATPase in sarcoplasmic reticulum. Biochim Biophys Acta 1991; 1064:335-42. [PMID: 1827997 DOI: 10.1016/0005-2736(91)90320-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The sarcoplasmic reticulum (SR) of skeletal muscle contains a 53 kDa glycoprotein of unknown function, as well as the (Ca(2+)-Mg2+)-ATPase. It has been suggested that the glycoprotein couples the hydrolysis of ATP by the ATPase to the transport of calcium. It has been shown that if SR vesicles are solubilized in cholate in media containing low K+ concentrations followed by reconstitution, then vesicles are formed containing the glycoprotein and with ATP hydrolysis coupled to Ca2+ accumulation, as shown by a large stimulation of ATPase activity by addition of A23187. In contrast, if SR vesicles are solubilized in media containing a high concentration of K+, then the vesicles that are produced following reconstitution lack the glycoprotein and show low stimulation by A23187 (Leonards, K.S. and Kutchai, H. (1985) Biochemistry 24, 4876-4884). We show that the effect of K+ on reconstitution does not follow from any changes in the amount of glycoprotein but rather from an effect of K+ on the detergent properties of cholate. In low K+ media, the cmc of cholate is high, cholate is a relatively poor detergent and incomplete solubilization results in 'reconstitution' of vesicles with the correct orientation of ATPase molecules. In high K+ media, the cmc of cholate is reduced and more complete solubilization of the SR leads to a true reconstitution with the formation of vesicles with a random orientation of ATPase molecules. The experiments provide no evidence for an effect of the glycoprotein on the (Ca(2+)-Mg2+)-ATPase.
Collapse
Affiliation(s)
- E A Grimes
- Department of Biochemistry, University of Southampton, U.K
| | | | | | | |
Collapse
|
9
|
Burgess AJ, Matthews I, Grimes EA, Mata AM, Munkonge FM, Lee AG, East JM. Chemical crosslinking and enzyme kinetics provide no evidence for a regulatory role for the 53 kDa glycoprotein of sarcoplasmic reticulum in calcium transport. Biochim Biophys Acta 1991; 1064:139-47. [PMID: 1827350 DOI: 10.1016/0005-2736(91)90420-d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
m-Maleimidobenzoyl-N-hydroxysuccinimide ester (MBS) was used to cross-link the protein components of rabbit skeletal muscle sarcoplasmic reticulum. Analysis of cross-linked material by SDS-polyacrylamide gel electrophoresis showed that both the (Ca(2+)-Mg2+)-ATPase and the 53 kDa glycoprotein could be cross-linked, since the amount of protein at the locations on the gel corresponding to uncross-linked material was reduced in the presence of 1.0 mM MBS. Cross-linked products of 130 kDa, 200-260 kDa and approx. 300 kDa were identified. Probing the cross-linked products with monoclonal antibodies against ATPase, 53 kDa glycoprotein and calsequestrin revealed no cross-linked products containing the ATPase and either calsequestrin or the 53 kDa glycoprotein over the range of molecular weights examined here. Possible interactions between the ATPase and calsequestrin or the 53 kDa glycoprotein were also investigated by studying the ATPase activity for the purified ATPase and for the ATPase in sarcoplasmic reticulum vesicles made permeable to Ca2+ with A23187. Effects of Ca2+ and ATP on the two systems were indistinguishable, providing no evidence for a major modulatory role of calsequestrin or the 53 kDa glycoprotein on the ATPase.
Collapse
Affiliation(s)
- A J Burgess
- Department of Biochemistry, University of Southampton, U.K
| | | | | | | | | | | | | |
Collapse
|
10
|
Affiliation(s)
- R I Norman
- Department of Medicine, University of Leicester, United Kingdom
| | | | | |
Collapse
|
11
|
Burgess AJ, Norman RI. The large glycoprotein subunit of the skeletal muscle voltage-sensitive calcium channel. Deglycosylation and development. Eur J Biochem 1988; 178:527-33. [PMID: 2850183 DOI: 10.1111/j.1432-1033.1988.tb14479.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Deglycosylation was used to assess the size of the core polypeptide of the large alpha 2-glycoprotein subunit of the 1,4-dihydropyridine-sensitive calcium channel from rabbit skeletal muscle. The extent of glycosylation was assessed by measuring the shift in apparent molecular mass of the alpha 2 component following electrophoresis in sodium dodecyl sulphate/polyacrylamide gels, using anti-(alpha 2-subunit) monoclonal antibody staining of immunoblots. Chemical deglycosylation with trifluoromethanesulphonic acid produced a shift in apparent molecular mass of the alpha 2 component from Mr 140,000 to Mr 105,000, consistent with a carbohydrate content of approximately 25%. Enzymatic treatments were insufficient to deglycosylate the alpha 2 subunit fully, possibly due to the inaccessibility of glycosidic bonds to enzyme attack. Enzymatic deglycosylation procedures did, however, reduce the 1,4-dihydropyridine-binding activity of transverse-tubule membranes. Neuraminidase alone or together with endo-beta-N-acetylglucosaminidase (endoglycosidase F) reduced the number of sites for (+)[3H]PN 200-110 by 73 +/- 2% and 77 +/- 5% respectively, with no change in apparent dissociation constant, implying a possible role for the glycosylated subunits in the binding of 1,4-dihydropyridines to the calcium-channel complex. The development of the alpha 2 component in rat skeletal muscle was shown to be indistinguishable from the appearance of 1,4-dihydropyridine binding activity consistent with the involvement of the alpha 2 subunit in the calcium-channel complex at all stages of development.
Collapse
Affiliation(s)
- A J Burgess
- Department of Medicine, Leicester Royal Infirmary, England
| | | |
Collapse
|
12
|
Burgess AJ, Norman RI. Characterization of calcium channel subunit. Biochem Soc Trans 1988; 16:452-4. [PMID: 2850232 DOI: 10.1042/bst0160452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- A J Burgess
- Department of Medicine, University of Leicester, U.K
| | | |
Collapse
|
13
|
Norman RI, Burgess AJ, Allen E, Harrison TM. Monoclonal antibodies against the 1,4-dihydropyridine receptor associated with voltage-sensitive Ca2+ channels detect similar polypeptides from a variety of tissues and species. FEBS Lett 1987; 212:127-32. [PMID: 2433159 DOI: 10.1016/0014-5793(87)81570-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Four monoclonal antibodies have been raised against voltage-sensitive Ca2+ channel dihydropyridine receptors from rabbit skeletal muscle. When tested by immunoblot assay of denatured transverse tubule membranes in reducing polyacrylamide gels, each recognised a single polypeptide of Mr approximately 140,000 that co-migrated with the large glycoprotein subunit of the purified receptor. In blots of nonreducing gels, a larger protein of Mr approximately 170,000 was seen and three of the antibodies recognised additional components at Mr approximately 310,000 and approximately 330,000. Crossreactive material of similar molecular mass was also seen in rabbit heart and brain, and in the skeletal muscle of other species.
Collapse
|
14
|
Mayhew TM, Burgess AJ, Gregory CD, Atkinson ME. On the problem of counting and sizing mitochondria: a general reappraisal based on ultrastructural studies of mammalian lymphocytes. Cell Tissue Res 1979; 204:297-303. [PMID: 317012 DOI: 10.1007/bf00234641] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The authors ask the question whether the parameters "numbers" and "volume" are suitable for the morphometric analysis of mitochondria. In several types of cell, irregularity of mitochondrial shape makes it technically difficult, if not impossible, to obtain reliable stereological estimates of mean organelle volume or number per unit volume. Of more fundamental concern is whether number of mitochondria per cell is of any real value as a structural correlate of respiratory potential and hence as a measure of cell function. Alternative parameters might serve better for this purpose. Though the problem is illustrated by reference to quantitative studies of lymphocytes, it is also pertinent to the investigation of many other cell types.
Collapse
|