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1.
Diabet Med ; 37(4): 657-664, 2020 04.
Article in English | MEDLINE | ID: mdl-31769551

ABSTRACT

AIMS: To explore parental perspectives after flash glucose monitoring commencement in adolescents and young adults with type 1 diabetes who were not meeting glycaemic targets. METHODS: Twelve semi-structured interviews were conducted among parents of adolescents and young adults between the ages of 14 and 20 years (inclusive) with type 1 diabetes and not meeting glycaemic targets [HbA1c 81-130 mmol/mol (9.6-14.0%)] participating in a randomized controlled trial. Interviews were transcribed, then thematic analysis was performed to identify themes regarding parental experiences. RESULTS: Four key themes were found: flash glucose monitoring improved parental emotional well-being; flash glucose monitoring reduced diabetes-specific conflict within families; flash glucose monitoring facilitated the parental role in diabetes management; and sensor-related challenges, particularly sensors falling off, interfered with using flash glucose monitoring for diabetes management. The cost of self-funded sensors was the only barrier to continuing flash glucose monitoring that parents reported. CONCLUSIONS: This study provides new insights into the potential benefits and challenges of flash glucose monitoring use, drawn from the perspective of parents of adolescents and young adults not meeting glycaemic targets. As parents are often key partners in obtaining or purchasing this technology, these findings can be used to further inform parental expectations of this technology.


Subject(s)
Diabetes Mellitus, Type 1/blood , Glycemic Control , Parents/psychology , Perception , Adolescent , Adult , Blood Glucose/metabolism , Blood Glucose Self-Monitoring/instrumentation , Blood Glucose Self-Monitoring/methods , Cross-Over Studies , Diabetes Mellitus, Type 1/psychology , Diabetes Mellitus, Type 1/therapy , Equipment and Supplies , Female , Glycated Hemoglobin/metabolism , Glycemic Control/instrumentation , Glycemic Control/methods , Glycemic Control/standards , Humans , Interviews as Topic , Male , Middle Aged , Parent-Child Relations , Patient Care Planning/standards , Perception/physiology , Qualitative Research , Surveys and Questionnaires , Young Adult
2.
J Diabetes Metab Disord ; 18(1): 81-88, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31275878

ABSTRACT

AIMS: Insulin pump failure and adverse events are common and therefore anticipatory education is recommended. Research in other chronic diseases shows written action plans improve confidence and adherence during an acute deterioration. However, no similar data exists for patients with type one diabetes mellitus provided with anticipatory education via an insulin pump action plan. This study evaluates whether an insulin pump action plan improves patient and caregiver confidence in managing a potential pump failure without a subsequent increase in anxiety. METHODS: Adults with type one diabetes mellitus and caregivers of children with type 1 diabetes on continuous subcutaneous insulin infusions across four New Zealand diabetes services participated. Participants completed a questionnaire examining pump-related adverse events and self-reported confidence and anxiety in managing pump failure. An insulin pump action plan and focused education by their diabetes team was provided, with a follow-up questionnaire at least 3 months later. RESULTS: 174/270 pump patients participated initially, with a follow-up response rate of 84.5% (147/174). Despite prior provision, many could not recall having an insulin pump action plan at study commencement (101/174, 58%), and of these 92% stated they would have liked one. Patients had good levels of confidence in the reliability of their pump and infusion sets/sites (Likert scores of 4.4/5 and 3.95/5) which was not undermined by the insulin pump action plan. Confidence in managing a potential pump failure showed a small but significant increase (3.66/5 to 3.95/5, p = 0.004) present in both adults and parents, with anxiety also showing a small increase (2.16/5 to 2.38/5, p = 0.012). CONCLUSION: Patient recall of prior insulin pump action plan education is poor, with the vast majority of patients interested in further written anticipatory education regarding potential pump failure. The provision of an insulin pump action plan increases self-reported confidence in managing unexpected pump failure with a small associated increase in anxiety.

3.
Plant Reprod ; 32(2): 153-166, 2019 06.
Article in English | MEDLINE | ID: mdl-30430247

ABSTRACT

KEY MESSAGE: Complex protein-containing reproductive secretions are a conserved trait amongst all extant gymnosperms; the pollination drops of most groups include carbohydrate-modifying enzymes and defence proteins. Pollination drops are aqueous secretions that receive pollen and transport it to the ovule interior in gymnosperms (Coniferales, Cycadales, Ginkgoales, Gnetales). Proteins are well established as components of pollination drops in conifers (Coniferales) and Ephedra spp. (Gnetales), but it is unknown whether proteins are also present in the pollination drops of cycads (Cycadales), Ginkgo (Ginkgoales), Gnetum (Gnetales), or in the pollination drops produced by sterile ovules occurring on pollen plants in the Gnetales. We used liquid chromatography-tandem mass spectrometry followed by database-derived protein identification to conduct proteomic surveys of pollination drops collected from: Ceratozamia hildae, Zamia furfuracea and Cycas rumphii (Cycadales); Ginkgo biloba (Ginkgoales); Gnetum gnemon and Welwitschia mirabilis, including pollination drops from both microsporangiate and ovulate plants (Gnetales). We identified proteins in all samples: C. hildae (61), Z. furfuracea (40), C. rumphii (9), G. biloba (57), G. gnemon ovulate (17) and sterile ovules from microsporangiate plants (25) and W. mirabilis fertile ovules (1) and sterile ovules from microsporangiate plants (138). Proteins involved in defence and carbohydrate modification occurred in the drops of most groups, indicating conserved functions for proteins in pollination drops. Our study demonstrates that all extant gymnosperm groups produce complex reproductive secretions containing proteins, an ancient trait that likely contributed to the evolutionary success of seed plants.


Subject(s)
Cycadopsida/physiology , Plant Proteins/metabolism , Pollination/physiology , Proteomics , Biological Evolution , Ovule/physiology , Phenotype , Pollen/physiology , Reproduction
4.
Ann Bot ; 121(3): 483-488, 2018 03 05.
Article in English | MEDLINE | ID: mdl-29293875

ABSTRACT

Background and Aims: The leaf axis of members of the order Cycadales ('cycads') has long been recognized by its configuration of independent vascular bundles that, in transverse section, resemble the Greek letter omega (hence the 'omega pattern'). This provides a useful diagnostic character for the order, especially when applied to paleobotany. The function of this pattern has never been elucidated. Here we provide a three-dimensional analysis and explain the pattern in terms of the hydraulic architecture of the pinnately compound cycad leaf. Methods: The genus Cycas was used as a simple model, because each leaflet is supplied by a single vascular bundle. Sequential sectioning was conducted throughout the leaf axis and photographed with a digital camera. Photographs were registered and converted to a cinematic format, which provided an objective method of analysis. Key Results: The omega pattern in the petiole can be sub-divided into three vascular components, an abaxial 'circle', a central 'column' and two adaxial 'wings', the last being the only direct source of vascular supply to the leaflets. Each leaflet is supplied by a vascular bundle that has divided or migrated directly from the closest wing bundle. There is neither multiplication nor anastomoses of vascular bundles in the other two components. Thus, as one proceeds from base to apex along the leaf axis, the number of vascular bundles in circle and column components is reduced distally by their uniform migration throughout all components. Consequently, the distal leaflets are irrigated by the more abaxial bundles, guaranteeing uniform water supply along the length of the axis. Conclusions: The omega pattern exemplifies one of the many solutions plants have achieved in supplying distal appendages of an axis with a uniform water supply. Our method presents a model that can be applied to other genera of cycads with more complex vascular organization.


Subject(s)
Cycadopsida/anatomy & histology , Plant Leaves/anatomy & histology , Cycadopsida/physiology , Cycadopsida/ultrastructure , Models, Biological , Plant Leaves/physiology , Plant Leaves/ultrastructure , Water/metabolism
5.
Ann Bot ; 120(6): 923-936, 2017 Nov 28.
Article in English | MEDLINE | ID: mdl-29045531

ABSTRACT

BACKGROUND AND AIMS: Gymnosperms are either wind-pollinated (anemophilous) or both wind- and insect-pollinated (ambophilous). Regardless of pollination mode, ovular secretions play a key role in pollen capture, germination and growth; they are likely also involved in pollinator reward. Little is known about the broad-scale diversity of ovular secretions across gymnosperms, and how these may relate to various reproductive functions. This study analyses the sugar and amino acid profiles of ovular secretions across a range of ambophilous (cycads and Gnetales) and anemophilous gymnosperms (conifers) to place them in an evolutionary context of their possible functions during reproduction. METHODS: Ovular secretions from 13 species representing all five main lineages of extant gymnosperms were sampled. High-performance liquid chromatography techniques were used to measure sugar and amino acid content. Multivariate statistics were applied to assess whether there are significant differences in the chemical profiles of anemophilous and ambophilous species. Data were compared with published chemical profiles of angiosperm nectar. Chemical profiles were placed in the context of phylogenetic relationships. KEY RESULTS: Total sugar concentrations were significantly higher in ovular secretions of ambophilous species than wind-pollinated taxa such as Pinaceae and Cupressophyta. Ambophilous species had lower amounts of total amino acids, and a higher proportion of non-protein amino acids compared with anemophilous lineages, and were also comparable to angiosperm nectar. Results suggest that early gymnosperms likely had ovular secretion profiles that were a mosaic of those associated with modern anemophilous and ambophilous species. Ginkgo, thought to be anemophilous, had a profile typical of ambophilous taxa, suggesting that insect pollination either exists in Gingko, but is undocumented, or that its ancestral populations were insect-pollinated. CONCLUSIONS: Chemical profiles of ovular secretions of ambophilous gymnosperms show a clear signal of pollinator-driven selection, including higher levels of carbohydrates than anemophilous taxa, lower levels of amino acids, and the presence of specific amino acids, such as ß-alanine, that are known to influence insect feeding behaviour and physiology.


Subject(s)
Amino Acids/metabolism , Cycadopsida/metabolism , Ovule/metabolism , Pollination , Sugars/metabolism , Animals , Insecta/physiology , Phylogeny , Wind
6.
Acta Diabetol ; 53(6): 991-998, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27585938

ABSTRACT

AIMS: While there have been many outcome-focussed studies examining insulin pump therapy, only a few have looked at potential adverse events (AEs), with none examining the relationship between AEs and pump/infusion set type, ethnicity or socio-economic status. In addition, current data on the incidence and characteristics of pump-associated AEs are confined to one paediatric centre. We aimed to describe the incidence, characteristics and potential predictors of insulin pump-associated AEs in New Zealand adults and children with T1DM. METHODS: We approached adults and families of children with T1DM on insulin pumps in four main New Zealand centres. Participants completed a questionnaire examining pump-related issues they had experienced in the preceding 12 months. RESULTS: Response rate was 64 % with 174 of 270 eligible people participating in the study. 84 % of subjects reported one or more AEs, with an overall AE incidence of 3.42 per person/year (95 % CI 3.14, 3.73). An event serious enough to require a hospital presentation occurred in 9.8 %, all but one reporting high ketones or diabetic ketoacidosis (DKA). Set/site problems were the AE most commonly reported (by 53 % of respondents), followed by cutaneous complications (43 %) and pump malfunction (38 %). Few predictors of AEs (of any type) were found; however, a negative binomial regression model found that a longer duration of pumping (p = 0.018) and age <18 years (p = 0.043) were both associated with fewer AEs (all types combined). CONCLUSIONS: Insulin pump-associated AEs are very common. However, few variables are predictive of them with no relationships seen with glycaemic control, socio-economic status, pump manufacturer or infusion set type. Based on these findings, AEs should be anticipated in both adults and children, with anticipatory patient education and training recommended for their successful and safe use.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetic Ketoacidosis , Equipment Failure/statistics & numerical data , Insulin Infusion Systems , Insulin , Adolescent , Adult , Blood Glucose/analysis , Child , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/epidemiology , Diabetic Ketoacidosis/epidemiology , Diabetic Ketoacidosis/etiology , Female , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Incidence , Insulin/administration & dosage , Insulin/adverse effects , Insulin Infusion Systems/adverse effects , Insulin Infusion Systems/statistics & numerical data , Male , Middle Aged , New Zealand/epidemiology , Social Class , Time Factors
7.
Am J Bot ; 102(8): 1250-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26290548

ABSTRACT

UNLABELLED: • PREMISE OF THE STUDY: The presence of gelatinous (tension) fibers (GFs) in the roots of two extant cycadales (Cycas and Zamia) in a recent publication raises interesting issues of GF distribution in seed plants. An immediate question that arises from this discovery is whether GFs occur consistently in the radicle of all extant cycad genera and therefore might have a similar role in root contraction. We present results of a survey of nursery-grown material of all 10 genera.• METHODS: We sequentially sectioned seedling root material and used simple staining and histochemical methods to follow anatomical changes along the radicle of all 10 genera.• KEY RESULTS: We found GFs in nine genera; Stangeria appears to be the only genus without them. In all genera, there is a wide variation in the number of GFs and also variation in the development of thickened, fleshy roots. "Tertiary expansion" is a useful term to describe late cell division and enlargement of both primary and secondary parenchyma, the latter produced by the vascular cambium. Certain other histological features can be diagnostically useful at the generic level.• CONCLUSIONS: The functional interpretation of GFs as being wholly responsible for apparent tissue contraction is now somewhat compromised, especially as distortion of tracheary elements by changes in dimensions of parenchyma cells can falsely suggest root contraction when it may not occur. These preliminary results point the way to a more precise investigation of study material grown in more uniform environments using advanced technological methods.


Subject(s)
Cycadopsida/cytology , Gelatin/metabolism , Plant Roots/cytology , Cycadopsida/physiology , Plant Roots/physiology , Seedlings/cytology , Seedlings/physiology
8.
Am J Bot ; 101(8): 1275-85, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25077507

ABSTRACT

UNLABELLED: • PREMISE OF THE STUDY: Reaction wood (RW) in seed plants can induce late and usually secondary changes in organ orientation. Conifers produce compression wood (CW), generated by compression tracheids, which generate a push force. Angiosperms produce tension wood (TW), generated by tension wood fibers (TWF) often described as "gelatinous fibers," which exert a pull force. Usually RW is produced eccentrically, but it can occur concentrically, as in aerial roots of Ficus. However, gymnosperms can produce gelatinous fibers (tension fibers, TF), as in cortical and secondary phloem tissues (Gnetum). TFs are therefore limited neither to wood, xylem, nor angiosperms. Here we demonstrate that TFs in secondary phloem are involved in contraction of roots of cycads and compare them with TFs of Ficus.• METHODS: We sectioned root material of cycads at various stages of seedling development using simple staining and histochemical procedures to follow the course of secondary phloem development. Aerial roots of Ficus were compared with the cycad root material.• KEY RESULTS: Tension fibers (gelatinous fibers) occur extensively and continuously in the secondary phloem in roots that undergo contraction. Older tissues, but notably the xylem, become distorted by contraction. TFs in cycads correspond in cell wall features to TFs that occur in Ficus, but do not occur in secondary xylem. The individual fibers visibly contract.• CONCLUSIONS: Tissue contraction in Cycas and Zamia corresponds to that found in angiosperms and Gnetum and further broadens the scope of the activity of tension tissues. This finding possibly indicates that gelatinous fibers originated at a very early period of seed plant evolution.


Subject(s)
Cycas/cytology , Phloem/cytology , Plant Cells/physiology , Plant Roots/cytology , Zamiaceae/cytology , Biological Evolution , Cell Wall , Cycadopsida , Cycas/physiology , Ficus/cytology , Gelatin , Gnetum , Phloem/physiology , Plant Roots/physiology , Seedlings/cytology , Seedlings/physiology , Xylem/cytology , Zamiaceae/physiology
9.
Ann Bot ; 114(2): 233-42, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24942001

ABSTRACT

BACKGROUND AND AIMS: Species in the holoparasitic plant family Rafflesiaceae exhibit one of the most highly modified vegetative bodies in flowering plants. Apart from the flower shoot and associated bracts, the parasite is a mycelium-like endophyte living inside their grapevine hosts. This study provides a comprehensive treatment of the endophytic vegetative body for all three genera of Rafflesiaceae (Rafflesia, Rhizanthes and Sapria), and reports on the cytology and development of the endophyte, including its structural connection to the host, shedding light on the poorly understood nature of this symbiosis. METHODS: Serial sectioning and staining with non-specific dyes, periodic-Schiff's reagent and aniline blue were employed in order to characterize the structure of the endophyte across a phylogenetically diverse sampling. KEY RESULTS: A previously identified difference in the nuclear size between Rafflesiaceae endophytes and their hosts was used to investigate the morphology and development of the endophytic body. The endophytes generally comprise uniseriate filaments oriented radially within the host root. The emergence of the parasite from the host during floral development is arrested in some cases by an apparent host response, but otherwise vegetative growth does not appear to elicit suppression by the host. CONCLUSIONS: Rafflesiaceae produce greatly reduced and modified vegetative bodies even when compared with the other holoparasitic angiosperms once grouped with Rafflesiaceae, which possess some vegetative differentiation. Based on previous studies of seeds together with these findings, it is concluded that the endophyte probably develops directly from a proembryo, and not from an embryo proper. Similarly, the flowering shoot arises directly from the undifferentiated endophyte. These filaments produce a protocorm in which a shoot apex originates endogenously by formation of a secondary morphological surface. This degree of modification to the vegetative body is exceptional within angiosperms and warrants additional investigation. Furthermore, the study highlights a mechanical isolation mechanism by which the host may defend itself from the parasite.


Subject(s)
Endophytes/physiology , Flowers/anatomy & histology , Magnoliopsida/anatomy & histology , Magnoliopsida/microbiology , Endophytes/cytology , Plant Roots/anatomy & histology , Plant Roots/microbiology , Plant Shoots/microbiology
10.
Am J Bot ; 100(3): 461-4, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23455481

ABSTRACT

Woody stems that have completed some maturation of metaxylem elements should not be capable of further axial extension ("secondary stem lengthening"). However, this mechanism has been claimed by Renninger and Phillips (American Journal of Botany 99: 607-613) to be a feature of the palm Iriartea deltoidea. In response, we describe structural features of palm stems based on extensive known features of their anatomy and development. In addition to the inability of metaxylem vessels to extend after they are mature, fully differentiated fibers of the vascular bundle sheath, which would exist at the time of proposed stem elongation would not be capable of belated extension. "Vessel spirals" claimed by these authors to be capable of stretching to accommodate secondary stem lengthening does not refer to well-established features of the course of vascular bundles. The approach adopted by Renninger and Phillips simply measures stems of different sizes as an implied developmental series. Consequently, results do not take into account changes in the development of the palm stem as it ages. The existence of secondary stem lengthening in the palm Iriartea deltoidea, something never before observed in any tree, cannot occur because it would indeed disrupt mature metaxylem vessels and would also require the secondary extension of mature lignified fibers.


Subject(s)
Arecaceae/anatomy & histology , Arecaceae/growth & development , Plant Stems/anatomy & histology , Plant Stems/growth & development , Trees/anatomy & histology , Trees/growth & development
11.
Am J Bot ; 99(12): 1891-902, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23221497

ABSTRACT

Longevity, or organismal life span, is determined largely by the period over which constituent cells can function metabolically. Plants, with modular organization (the ability continually to develop new organs and tissues) differ from animals, with unitary organization (a fixed body plan), and this difference is reflected in their respective life spans, potentially much longer in plants than animals. We draw attention to the observation that palm trees, as a group of monocotyledons without secondary growth comparable to that of lignophytes (plants with secondary growth from a bifacial cambium), retain by means of sustained primary growth living cells in their trunks throughout their organismal life span. Does this make palms the longest-lived trees because they can grow as individuals for several centuries? No conventional lignophyte retains living metabolically active differentiated cell types in its trunk for this length of time, even though the tree as a whole can exist for millennia. Does this contrast also imply that the long-lived cells in a palm trunk have exceptional properties, which allows this seeming immortality? We document the long-life of many tall palm species and their inherent long-lived stem cell properties, comparing such plants to conventional trees. We provide a summary of aspects of cell age and life span in animals and plants. Cell replacement is a feature of animal function, whereas conventional trees rely on active growth centers (meristems) to sustain organismal development. However, the long persistence of living cells in palm trunks is seen not as evidence for unique metabolic processes that sustain longevity, but is a consequence of unique constructional features. This conclusion suggests that the life span of plant cells is not necessarily genetically determined.


Subject(s)
Arecaceae/cytology , Arecaceae/growth & development , Plant Stems/cytology , Plant Stems/growth & development , Animals , Arecaceae/anatomy & histology , Arecaceae/physiology , Cellular Senescence , Plant Stems/anatomy & histology , Plant Stems/physiology , Plant Vascular Bundle/anatomy & histology , Plant Vascular Bundle/cytology , Plant Vascular Bundle/genetics , Plant Vascular Bundle/physiology , Plants , Trees/anatomy & histology , Trees/cytology , Trees/growth & development , Trees/physiology
12.
Ann Bot ; 107(6): 909-16, 2011 May.
Article in English | MEDLINE | ID: mdl-21335327

ABSTRACT

BACKGROUND AND AIMS: Conifers are characterized by the paucity of axillary buds which in dicotyledonous trees usually occur at every node. To compensate, conifers also produce 'axillary meristems', which may be stimulated to late development. In juvenile material of Wollemia nobilis (Araucariaceae: Massart's model) first-order (plagiotropic) branches lack both axillary buds and, seemingly, axillary meristems. This contrasts with orthotropic (trunk) axes, which produce branches, either within the terminal bud or as reiterated orthotropic axes originating from axillary meristems. However, plagiotropic axes do produce branches if they are decapitated. This study investigated how this can occur if axillary meristems are not the source. METHODS: The terminal buds of a series of plagiotropic branches on juvenile trees were decapitated in order to generate axillary shoots. Shoots were culled at about weekly intervals to obtain stages in lateral shoot development. Serial sections were cut with a sliding microtome from the distal end of each sample and scanned sequentially for evidence of axillary meristems and early bud development. KEY RESULTS: Anatomical search produced no clear evidence of pre-existing axillary meristems but did reveal stages of bud initiation. Buds were initiated in a group of small starch-rich cortical cells. Further development involved de-differentiation of these small cells and the development of contrasting outer and inner regions. The outer part becomes meristematic and organizes the apex of the new branch. The inner part develops a callus-like tissue of vacuolated cells within which vascular cambia are developed. This kind of insertion of a branch on the parent axis seems not to have been described before. CONCLUSIONS: Axillary meristems in Wollemia characterize the leaf axils of trunk axes so that the origin of reiterated shoots is clear. Plagiotropic axes seemingly lack axillary meristems but still produce axillary branches by distinctive developmental processes. These observations demonstrate limited understanding of branch initiation in trees generally.


Subject(s)
Meristem/growth & development , Tracheophyta/growth & development , Plant Leaves/anatomy & histology , Plant Leaves/growth & development , Plant Shoots/anatomy & histology , Plant Shoots/growth & development , Tracheophyta/anatomy & histology
14.
J Hand Surg Eur Vol ; 35(3): 232-3, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20007415

ABSTRACT

The aim of this randomized controlled study was to determine whether administration of lignocaine with adrenaline is less painful when injected at room temperature compared to refrigerated temperature. A cohort of 50 patients undergoing unilateral carpal tunnel decompression was randomized to room temperature or refrigerated local anaesthetic. Pain scores were assessed using a 10 mm visual analogue scale. Mean pain scores were 4.0 (SD +/- 1.5) for room temperature and 6.5 (SD +/- 1.7) for refrigerated local anaesthetic (P < 0.001). This study demonstrates that patients experience greater pain levels with administration of local anaesthetic at refrigerated temperatures prior to open carpal tunnel release.


Subject(s)
Anesthetics, Local/administration & dosage , Carpal Tunnel Syndrome/surgery , Lidocaine/administration & dosage , Aged , Aged, 80 and over , Cold Temperature , Female , Humans , Injections , Male , Middle Aged , Pain Measurement , Prospective Studies , Refrigeration
15.
Am J Bot ; 96(10): 1787-97, 2009 Oct.
Article in English | MEDLINE | ID: mdl-21622299

ABSTRACT

We present a preliminary description of the morphology and anatomy of contrasted axes in the recently discovered conifer Wollemia nobilis, based on clonally propagated material. The novelty of this discovery and the tree's size and rarity has led to global interest and a comprehensive and successful conservation program. Our results should serve as a model on which future studies of this tree and other members of the Araucariaceae can be based. The specimens studied are mimics of the architecture of the mature tree, with precise distinction between orthotropic (= trunk) axes, which have radial symmetry (spiral phyllotaxy) and plagiotropic (= branch) axes with dorsiventral symmetry (as a modified decussate phyllotaxy). Trunk axes develop irregular pseudowhorls of branches that originate within the terminal bud by syllepsis, their extension coincident with that of the parent axis. The two kinds of axes show considerable anatomical differences, but are still based on the common feature of a single stelar-derived trace to each leaf that becomes subdivided in the cortex, a feature of the whole family. Trunk axes include extended cortical leaf and branch traces associated with abundant sclerenchyma, but branches have short cortical leaf traces, no branch traces, and limited sclerenchyma. Reiteration is limited and largely involves the formation of basal suckers on the trunk. Branches normally remain unbranched, but can do so most often when damaged. This study thus emphasizes the phenomenon of axis differentiation in conifers, which has been little investigated anatomically, but could be very important in the identification of fossils.

16.
Am J Bot ; 96(8): 1462-86, 2009 Aug.
Article in English | MEDLINE | ID: mdl-21628293

ABSTRACT

The unique properties of tree building in Arecaceae strongly constrain their architectural lability. Potentially compensating for this limitation, the extensive diversification of leaf anatomical structure within palms involves many characters whose alternate states may confer disparate mechanical or physiological capabilities. In the context of a recent global palm phylogeny, we analyzed the evolution of 10 such lamina anatomical characters and leaf morphology of 161 genera, conducting parsimony and maximum likelihood ancestral state reconstructions, as well as tests of correlated evolution. Lamina morphology evolves independently from anatomy. Although many characters do optimize as synapomorphic for major clades, anatomical evolution is highly homoplasious. Nevertheless, it is not random: analyses indicate the recurrent evolution of different cohorts of correlated character states. Notable are two surface layer (epidermis and hypodermis) types: (1) a parallel-laminated type of rectangular epidermal cells with sinuous anticlinal walls, with fibers present in the hypodermis and (2) a cross-laminated type of hexagonal cells in both layers. Correlated with the cross-laminated type is a remarkable decrease in the volume fraction of fibers, accompanied by changes in the architecture and sheath cell type of the transverse veins. We discuss these and other major patterns of anatomical evolution in relation to their biomechanical and ecophysiological significance.

18.
Hand Surg ; 11(1-2): 5-8, 2006.
Article in English | MEDLINE | ID: mdl-17080521

ABSTRACT

Pain and disability caused by ganglia of the hand and wrist were assessed using a patient-rated wrist evaluation questionnaire in 75 patients. Dorsal wrist ganglia were the most painful and disabling. However, the majority of ganglia cause little pain or disability. Consequently, referral by General Practitioners should be confined to those with pain, disability or failure of conservative management.


Subject(s)
Activities of Daily Living , Ganglion Cysts/complications , Pain/etiology , Disability Evaluation , Female , Ganglion Cysts/pathology , Hand , Humans , Male , Needs Assessment , Pain Measurement , Primary Health Care , Referral and Consultation , Wrist
19.
Br Dent J ; 200(11): 621-3; discussion 617, 2006 Jun 10.
Article in English | MEDLINE | ID: mdl-16767140

ABSTRACT

OBJECTIVES: To discover what dentists require of a hospital response letter with regards to content and timeliness. DESIGN: Postal survey. SETTING: South Wales. SUBJECTS AND METHODS: A postal questionnaire was issued to all dentists (n = 256) who had referred a patient to the dental hospital between 1 January 2003 and 1 March 2003. RESULTS: The response rate was 60.2% (154). The preferred time frame for the receipt of a letter following a patient's appointment was one to three weeks for 96.4% (n = 133) of respondents, but 58.4% believed that they currently do not receive responses within this time frame. The preferred method of communication remained the letter (n = 82, 53%), followed by the telephone (n = 58, 38%). E-mail accounted for eight percent (n = 12) of communication. Most respondents (70%, n = 107) were satisfied with the letters' content. Eight of the ten items of information suggested as being appropriate in a response letter were considered essential by 53.2% of dentists (n = 82), and 55.8% (n = 76) believed the remaining two items to be desirable. CONCLUSIONS: Dentists agree closely on the information required in a response letter and most are satisfied with the content of current response letters. However, many dentists believe response letters arrive later than three weeks after their patient's appointment.


Subject(s)
Dental Service, Hospital , Feedback , General Practice, Dental/statistics & numerical data , Interprofessional Relations , Referral and Consultation , Correspondence as Topic , Humans , Surveys and Questionnaires , Time Factors , Wales
20.
Br Dent J ; 200(7): 393-7, discussion 387, 2006 Apr 08.
Article in English | MEDLINE | ID: mdl-16607332

ABSTRACT

AIMS: To identify the number of claims reported by the Dental Practice Board (DPB) for the three adult preventive codes for the year ending October 2002 in Wales. To identify the attitudes of practitioners to the use of these codes. DESIGN: A cross-sectional study using routinely gathered DPB data and data generated by a postal questionnaire. SAMPLE: All DPB claims for the 12 months ending October 2002. A randomised sample of 400 dentists currently practising in Wales for the postal questionnaire. RESULTS: The DPB data showed great variation across Wales for: the number, type and distribution of preventive code claims; the age and payment status of patients prescribed these treatments; and the proportion of male versus female dentists claiming for the codes. The questionnaire response rate was 67% (n = 267). The results showed that most respondents were deterred by the restrictions on the codes, insufficient reimbursement and a perceived unwillingness of patients to pay for preventive care. CONCLUSION: Few dentists provide preventive care to adults under the existing remuneration system. Work is necessary to enable dentists to use effective preventive techniques for adult patients. These results can be considered to show the baseline provision of prevention and could facilitate the evaluation of any changes to the current system.


Subject(s)
Attitude of Health Personnel , Dental Health Services , Dentists/psychology , Preventive Dentistry , State Dentistry , Adolescent , Adult , Age Factors , Aged , Attitude to Health , Cariostatic Agents/therapeutic use , Cross-Sectional Studies , Dental Health Services/statistics & numerical data , Female , Fluorides, Topical/therapeutic use , Health Promotion , Humans , Male , Middle Aged , Patient Education as Topic , Patients/psychology , Pilot Projects , Pit and Fissure Sealants/therapeutic use , Preventive Dentistry/statistics & numerical data , Reimbursement Mechanisms , State Dentistry/statistics & numerical data , Wales
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