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1.
Plant Biol (Stuttg) ; 24(3): 482-491, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35137516

ABSTRACT

Loss of sexual reproductive capacity has been proposed as a syndrome of domestication in vegetatively propagated crops, but there are relatively few examples from agricultural systems. In this study, we compare sexual reproductive capacity in wild (sexual) and domesticated (vegetative) populations of enset (Ensete ventricosum (Welw.) Cheesman), a tropical banana relative and Ethiopian food security crop. We examined floral and seed morphology and germination ecology across 35 wild and domesticated enset. We surveyed variation in floral and seed traits, including seed weight, viability and internal morphology, and germinated seeds across a range of constant and alternating temperature regimes to characterize optimum germination requirements. We report highly consistent floral allometry, seed viability, internal morphology and days to germination in wild and domesticated enset. However, seeds from domesticated plants responded to cooler temperatures with greater diurnal range. Shifts in germination behaviour appear concordant with a climatic envelope shift in the domesticated distribution. Our findings provide evidence that sexual reproductive capacity has been maintained despite long-term near-exclusive vegetative propagation in domesticated enset. Furthermore, certain traits such as germination behaviour and floral morphology may be under continued selection, presumably through rare sexually reproductive events. Compared to sexually propagated crops banked as seeds, vegetative crop diversity is typically conserved in living collections that are more costly and insecure. Improved understanding of sexual propagation in vegetative crops may have applications in germplasm conservation and plant breeding.


Subject(s)
Musaceae , Plant Breeding , Crops, Agricultural , Domestication , Ecology
2.
Plant Biol (Stuttg) ; 21(3): 515-522, 2019 May.
Article in English | MEDLINE | ID: mdl-30076674

ABSTRACT

Morphological and functional seed traits have important roles in characterising the species regeneration niche and help to understand the reproductive biology of rare and threatened plants, which can thus support appropriate plant conservation measures. Seed morphometric and dispersal kinetics of the critically endangered Dioscorea strydomiana were measured and compared with those of four other Dioscorea species, and seed germination response under constant temperatures (5-35 °C) was compared with that of the congeneric and widespread D. sylvatica. Seed mass of D. strydomiana (ca. 14 mg) was twice that of D. sylvatica, but similar to or smaller than the other species examined. Seeds of D. strydomiana have the lowest speed of descent and lowest variability in most of the morphological traits considered, suggesting lower phenotypic plasticity but higher variance in the wing-loading value. Seeds of D. strydomiana reached maximum germination at 15 °C (ca. 47%), which decreased slightly to ca. 37% at 25 °C and was completely inhibited at 35 °C. D. sylvatica seeds started to germinate at 10 °C (ca. 3%), reached 75-80% germination at 15-20 °C and maximum (ca. 90%) at 25-30 °C. Base temperatures for germination (Tb ) were 9.3 and 5.7 °C, for D. strydomiana and D. sylvatica, respectively. Due to the higher germination percentages of D. sylvatica, ceiling and optimum temperatures could also be modelled for this species, suggesting higher sensitivity to high temperature for seeds of D. strydomiana. The detected poor seed lot quality of D. strydomiana suggests difficulties in reproduction from seed, highlighting the need for further investigation and conservation actions for this threatened yam species.


Subject(s)
Dioscorea/physiology , Seeds/physiology , Germination/physiology , Plants, Medicinal/physiology , Temperature
3.
Sci Rep ; 7(1): 16653, 2017 11 30.
Article in English | MEDLINE | ID: mdl-29192145

ABSTRACT

Animals self-medicate using a variety of plant and arthropod secondary metabolites by either ingesting them or anointing them to their fur or skin apparently to repel ectoparasites and treat skin diseases. In this respect, much attention has been focused on primates. Direct evidence for self-medication among the great apes has been limited to Africa. Here we document self-medication in the only Asian great ape, orang-utans (Pongo pygmaeus), and for the first time, to our knowledge, the external application of an anti-inflammatory agent in animals. The use of leaf extracts from Dracaena cantleyi by orang-utan has been observed on several occasions; rubbing a foamy mixture of saliva and leaf onto specific parts of the body. Interestingly, the local indigenous human population also use a poultice of these leaves for the relief of body pains. We present pharmacological analyses of the leaf extracts from this species, showing that they inhibit TNFα-induced inflammatory cytokine production (E-selectin, ICAM-1, VCAM-1 and IL-6). This validates the topical anti-inflammatory properties of this plant and provides a possible function for its use by orang-utans. This is the first evidence for the deliberate external application of substances with demonstrated bioactive potential for self-medication in great apes.


Subject(s)
Behavior, Animal , Biological Products , Dracaena/chemistry , Plants, Medicinal , Pongo pygmaeus , Self Medication , Animals , Biological Products/chemistry , Biological Products/pharmacology , Biomarkers , Cell Line , Cytokines/metabolism , Dracaena/metabolism , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Humans , Inflammation Mediators/metabolism , Plant Extracts/chemistry , Plant Extracts/pharmacology
4.
Ann Bot ; 104(1): 125-42, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19451146

ABSTRACT

BACKGROUND AND AIMS: Gagea is a Eurasian genus of petaloid monocots, with a few species in North Africa, comprising between 70 and approximately 275 species depending on the author. Lloydia (thought to be the closest relative of Gagea) consists of 12-20 species that have a mostly eastern Asian distribution. Delimitation of these genera and their subdivisions are unresolved questions in Liliaceae taxonomy. The objective of this study is to evaluate generic and infrageneric circumscription of Gagea and Lloydia using DNA sequence data. METHODS: A phylogenetic study of Gagea and Lloydia (Liliaceae) was conducted using sequences of nuclear ribosomal internal transcribed spacer (ITS) and plastid (rpl16 intron, trnL intron, trnL-F spacer, matK and the psbA-trnH spacer) DNA regions. This included 149 accessions (seven as outgroups), with multiple accessions of some taxa; 552 sequences were included, of which 393 were generated as part of this research. KEY RESULTS: A close relationship of Gagea and Lloydia was confirmed in analyses using different datasets, but neither Gagea nor Lloydia forms a monophyletic group as currently circumscribed; however, the ITS and plastid analyses did not produce congruent results for the placement of Lloydia relative to the major groups within Gagea. Gagea accessions formed five moderately to strongly supported clades in all trees, with most Lloydia taxa positioned at the basal nodes; in the strict consensus trees from the combined data a basal polytomy occurs. There is limited congruence between the classical, morphology-derived infrageneric taxonomy in Gagea (including Lloydia) and clades in the present phylogenetic analyses. CONCLUSIONS: The analyses support monophyly of Gagea/Lloydia collectively, and they clearly comprise a single lineage, as some previous authors have hypothesized. The results provide the basis for a new classification of Gagea that has support from some morphological features. Incongruence between plastid and nuclear ITS results is interpreted as potentially due to ancient hybridization and/or paralogy of ITS rDNA.


Subject(s)
DNA, Plant/genetics , DNA, Ribosomal Spacer/genetics , Liliaceae/classification , Liliaceae/genetics , Plastids/genetics , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA
5.
J Psychiatr Ment Health Nurs ; 13(1): 12-8, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16441388

ABSTRACT

Once a person accepts any form of mainstream mental health care, she is faced with the paradox of disabling caring. Every time an emotionally distressed individual is professionally rescued, she forfeits a golden opportunity to discover and utilize her own healing potential. Yet within a mental health service that is heavily medicalized and investing more and more in time-limited therapies, can it ever be otherwise? Drawing on the developmental theory of Donald Winnicott, together with the poet John Keats' concept of 'Soul-making', this case study provides an account of therapy delivered from outside the parameters of a health-illness model of caring. It acknowledges human suffering as a natural and inevitable part of life and, whilst acknowledging the value of therapeutic companionship, proclaims the mentally distressed person as best placed to navigate her own recovery.


Subject(s)
Attitude of Health Personnel , Attitude to Health , Depressive Disorder/psychology , Nurse-Patient Relations , Psychiatric Nursing/methods , Self Care/psychology , Self Concept , Adaptation, Psychological , Adult , Altruism , Communication , Depressive Disorder/prevention & control , Empathy , Female , Human Development , Humans , Imagination , Maternal Behavior/psychology , Mother-Child Relations , Nurse's Role/psychology , Power, Psychological , Psychological Theory , Psychotherapy , Self Care/methods , Self Disclosure , Transference, Psychology
6.
J Psychiatr Ment Health Nurs ; 8(2): 115-20, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11882116

ABSTRACT

I begin with an Orwellian dilemma [Orwell G. (1968) The Collected Essays, Journalism and Letters of George Orwell, Vol. 1, p. 239. Harcourt Brace Jovanovich, New York]: do I 'shoot the elephant' (by writing the abstract) to impress the editor? Or, with the courage of my postmodern convictions, do I lay down my rifle and disregard such suppressive editorial instructions? Bang! My words strafe the paper and the elephant is dead. How difficult it is to stay standing against the powerful currents of the dominant tradition. How easy it is to disavow the inequalities and injustices of that tradition when your livelihood (and your ego) depends upon it. So goes the theme of my paper, that, despite the clarion calls of the illustrious minority to reject the patriarchal model of medical psychiatry, psychiatric nurses continue to be propelled by the twin engines of illness and diagnosis. Yet as soon as psychiatry encounters the 'other' it becomes, in Homi K. Bhabha's words, 'hybridized': a pregnant pause created from the seeds of two different cultures. In this sense, every psychiatric moment becomes a golden opportunity for the psychiatric nurse to abdicate her role as medical factotum. Freed from these contractual obligations, she can join the 'other' and share in his experiences, sustaining rather than negating him within a truly therapeutic alliance. In similar fashion, this article has become a mixture of rhetorical fluidity and structured reality: a hybridized compromise which acknowledges the journal's publication boundaries yet still revels, at times, in the freedom of an open and lyrical text.


Subject(s)
Philosophy, Medical , Philosophy, Nursing , Psychiatric Nursing/trends , Forecasting , Humans , Nurse's Role/psychology , Nursing Theory , Psychoanalytic Theory , United Kingdom
9.
Nurs Times ; 93(8): 48-9, 1997.
Article in English | MEDLINE | ID: mdl-9095972

ABSTRACT

This article explores why some nurses may resist the introduction of clinical supervision--either consciously or unconsciously. It lists suggestions and strategies for offering encouragement to those who are advocates of clinical supervision bit victims of avoidance techniques.


Subject(s)
Clinical Competence , Nursing Care/standards , Nursing, Supervisory , Humans , Interprofessional Relations
10.
J Exp Biol ; 199(Pt 5): 1073-83, 1996.
Article in English | MEDLINE | ID: mdl-9318891

ABSTRACT

This paper responds to research into the aerodynamics of flapping wings and to the problem of the lack of an adequate method which accommodates large-scale trailing vortices. A comparative review is provided of prevailing aerodynamic methods, highlighting their respective limitations as well as strengths. The main advantages of an unsteady aerodynamic panel method are then introduced and illustrated by modelling the flapping wings of a tethered sphingid moth and comparing the results with those generated using a quasi-steady method. The improved correlations of the aerodynamic forces and the resultant graphics clearly demonstrate the advantages of the unsteady panel method (namely, its ability to detail the trailing wake and to include dynamic effects in a distributed manner).

11.
J Appl Physiol (1985) ; 73(6): 2462-9, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1490959

ABSTRACT

It has been hypothesized that regulatory control in the respiratory system is state dependent. According to this view respiratory instability during sleep onset is a consequence of repeated fluctuations in arousal state. However, these speculations are based primarily on measurements during stable sleep, not during sleep onset itself. The aim of the present study was to assess changes in ventilation and gas tensions during sleep onset as a function of arousal state. Twenty-one subjects (12 males and 9 females, mean age 20 yr) were assessed over an average of 11.3 sleep onsets. The subject's state was classified as alpha, theta, body movement, or stage 2 sleep, and expiratory tidal volume, minute ventilation, respiratory rate, and end-tidal CO2 and O2 were measured by means of a face mask, valve, and pneumotachograph on a breath-by-breath basis. Respiratory instability during sleep onset was found to be a result of two factors. The first factor was a between-state effect in which transitions from alpha to theta were associated with falls, and from theta to alpha with increases, in ventilation. The magnitude of the change was a positive function of metabolic drive at the time of the state change (as indicated by alveolar PCO2 and PO2 levels). The second was a within-state effect in which ventilation fell during consecutive alpha breaths and increased during consecutive theta breaths. These changes were due to the influence of the relative hyperventilation of the alpha state and the relative hypoventilation of the theta state on metabolic drive.


Subject(s)
Respiration/physiology , Sleep/physiology , Adult , Alpha Rhythm , Blood Gas Analysis , Carbon Dioxide/analysis , Carbon Dioxide/blood , Female , Humans , Male , Oxygen Consumption/physiology , Respiratory Mechanics/physiology , Sex Characteristics , Theta Rhythm , Wakefulness/physiology
12.
Obstet Gynecol ; 76(1): 61-4, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2359567

ABSTRACT

Fifty placentas were collected at term from singleton pregnancies resulting from in vitro fertilization (IVF) and intrauterine embryo transfer. Their pathologic features were compared with those of a control group composed of 50 placentas obtained from spontaneous singleton pregnancies. The mean maternal age, mean gestational age, mean fetal weight, sex ratio, and rate of pregnancy complications did not differ. There was also no significant difference between the groups in the mean placental weight and in the incidence of placental pathologic lesions, including extended infarcts, massive perivillous fibrin depositions, chorioangiomas, and placental inflammatory lesions. The incidence of abnormal placental shapes was significantly (P less than .05) greater in the IVF group (22%) compared with the control group (6%). A significant (P less than .025) difference was observed between the groups in the distribution of umbilical cord insertions. The mean distance between the cord insertion and the closest placental margin was significantly (P less than .005) shorter in the group conceived by IVF (3.23 +/- 1.91 cm) than in the control group (4.54 +/- 2.42 cm). A relationship between these placental morphologic features and the superficial implantation and/or inadequate orientation of the blastocyst after IVF and intrauterine embryo transfer is proposed.


Subject(s)
Embryo Transfer , Fertilization in Vitro , Placenta/pathology , Adult , Female , Fibrin/analysis , Humans , Infarction/pathology , Organ Size , Placenta/blood supply , Pregnancy , Umbilical Cord/pathology
13.
Hum Pathol ; 20(5): 458-62, 1989 May.
Article in English | MEDLINE | ID: mdl-2707797

ABSTRACT

Embryonic vestiges of the umbilical cord are classic findings in routine morphologic examination of the placenta. In order to evaluate their clinicopathologic significance, we examined samples from the fetal and placental ends of 1,000 umbilical cords and collected the principal clinical findings of the corresponding newborns. Microscopic evidence of embryonic remnants were found in 231 cases (23.1%) divided into remnants of the allantoic duct (63%), the omphalomesenteric duct (6.6%), and the embryonic vessels (30.4%), including one case of hemangioma and an accessory small artery. There were no significant clinical differences between the three vestigial groups, and no particular association with congenital malformations or perinatal complications. In 70.9% of the cases, the embryonic remnants were found at the fetal end of the umbilical cord, where most tumors of the cord develop.


Subject(s)
Allantois/anatomy & histology , Blood Vessels/embryology , Extraembryonic Membranes/anatomy & histology , Umbilical Cord/anatomy & histology , Vitelline Duct/anatomy & histology , Hemangioma/pathology , Humans , Umbilical Cord/blood supply
15.
Article in French | MEDLINE | ID: mdl-2661647

ABSTRACT

The authors report on 80 cases of the syndrome of a single umbilical artery (SUA) and compare the anatomo-clinical features with the abnormalities found on ultrasound. The clinical results confirm the information given in the literature which is that there is a higher incidence of poor intra-uterine fetal growth (36.4%), of prematurity (16.3%), of associated congenital abnormalities (42%) and of perinatal mortality (21.3%). Ultrasound examination makes it possible to screen for associated major fetal malformations (26.6%) and of most cases of intra-uterine growth retardation (28.3%). The ultrasound detection of the absence of one of the umbilical arteries and of the associated fetal abnormalities together with the techniques for sampling fetal cells now causes change in the approach to these high risk pregnancies on the cytogenetic level as on the perinatal handling of this syndrome.


Subject(s)
Fetal Diseases/etiology , Pregnancy Complications, Cardiovascular/diagnosis , Ultrasonography , Umbilical Arteries/abnormalities , Adolescent , Adult , Female , Fetal Growth Retardation/etiology , Humans , Male , Pregnancy , Syndrome
16.
Article in French | MEDLINE | ID: mdl-2681367

ABSTRACT

Fifty cases of placental lesions detected by sonography during the second half of pregnancy were pathologically investigated. Sonographic evaluation included the size of the lesion, its echogenicity on subsequent examinations and location in relation to the placental margin and umbilical cord insertions. Classical pathologic examination was performed after delivery to confirm the ultrasonographic findings. The echogenic pattern of these lesions was distinct from that of the rest of the placenta and the lesions were classified in two categories. The parenchymal lesions including 19 intervillous thrombosis, 14 caverns, 3 cases of hydatidiform changes, 2 infarcts, 1 septal cyst and one case of fibrin deposition and, the chorionic lesions including 5 subchorionic thrombosis, 3 cases of extrachorial placentas and 2 amniotic cysts. Therefore diagnostic ultrasound gives the clinician a unique opportunity to perform detailed examination of the placenta in vivo and can be an effective and non-invasive way to diagnose different types of lesions that are usually described in the post-partum by the pathologist.


Subject(s)
Placenta Diseases/diagnosis , Ultrasonography , Female , Humans , Placenta Diseases/pathology , Pregnancy
17.
Rev Med Brux ; 10(1-2): 3-9, 1989.
Article in French | MEDLINE | ID: mdl-2928609

ABSTRACT

This investigation was undertaken to determine whether examination of the placenta contributed to a better understanding of the causes of fetal malformations. Specific histological abnormalities were found in triploidy and lysosomal storage disorders. Placentas from trisomies only showed a marked a specific retardation of villous maturation. The most frequent placental abnormalities detailed in cases presenting major fetal malformations with normal karyotype were: velamentous insertion of the umbilical cord, placental hypotrophy, single umbilical artery, marginal retroplacental hematoma and generalized perivillous fibrin deposition. Examination of the placenta after fetal malformation can provide helpful informations in counseling the parents and the perinatal team in the follow-up of any future child bearing.


Subject(s)
Congenital Abnormalities/etiology , Placenta/pathology , Female , Humans , Hydatidiform Mole/etiology , Infant, Newborn , Metabolism, Inborn Errors/etiology , Placenta Diseases/complications , Placenta Diseases/pathology , Polyploidy , Pregnancy , Trisomy
18.
Placenta ; 9(6): 607-13, 1988.
Article in English | MEDLINE | ID: mdl-2853352

ABSTRACT

A tumour occurring in an otherwise normal placenta presented the vascularity of a mature chorangioma but was surrounded by a neoplastic trophoblastic proliferation. A chorangioma with an atypical associated trophoblastic proliferation has never been reported in any of nearly 500 cases of chorangiomas described in the literature. The possibility of a combined lesion (for which we propose the term chorangiocarcinoma) is emphasized. It cannot be excluded however that chorangiomas could be, in rare cases, true neoplasms rather than hamartomas.


Subject(s)
Hemangioma/ultrastructure , Placenta/ultrastructure , Trophoblastic Neoplasms/ultrastructure , Uterine Neoplasms/ultrastructure , Chorionic Gonadotropin/analysis , Female , Humans , Immunohistochemistry , Microscopy , Microscopy, Electron , Placenta/pathology , Placental Lactogen/analysis , Pregnancy
19.
Obstet Gynecol ; 72(4): 577-81, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3047607

ABSTRACT

The pathologic findings in placentas from ten multiple gestations complicated by the so-called vanishing twin phenomenon were studied to confirm the ultrasonographic evidence. Five pregnancies resulted from in vitro fertilization and embryo transfer, and five conceptions were spontaneous. The pregnancies were studied by repeat ultrasound examinations between five and 12 weeks' gestation. First-trimester bleeding was the only clinical sign of this phenomenon. Postpartum evidence of the vanishing twin phenomenon was found in five cases. Morphologically, the lesions were characterized by well-delineated plaques of perivillous fibrin deposition, associated in one case with embryonic remnants. This focal degenerative change of the placental mass, which also exists in about 25% of placentas from uncomplicated term pregnancies, may be the only clue to the disappearance of one conceptus.


Subject(s)
Fetal Death/pathology , Placenta/pathology , Pregnancy, Multiple , Twins , Ultrasonography , Female , Humans , Pregnancy
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