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1.
Plant Biol (Stuttg) ; 25(3): 403-410, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36744723

ABSTRACT

Invasive plants displaying disparate pollination environments and abiotic conditions in native and non-native ranges provide ideal systems to test the role of different ecological factors driving flower colour variation. We quantified corolla reflectance of the ornithophilous South American Nicotiana glauca in native populations, where plants are pollinated by hummingbirds, and in populations from two invaded regions: South Africa, where plants are pollinated by sunbirds, and the Balearic island of Mallorca, where plants reproduce by selfing. Using visual modelling we examined how corolla reflectance could be perceived by floral visitors present in each region. Through Mantel tests we assessed a possible association between flower colour and different abiotic factors. Corolla reflectance variation (mainly along medium to long wavelengths, i.e. human green-yellow to red colours) was greater among studied regions than within them. Flower colour was more similar between South America and South Africa, which share birds as pollinators. Within invaded regions, corolla reflectance variation was lower in South Africa, where populations could not be distinguished from each other by sunbirds, than in Spain, where populations could be distinguished from each other by their occasional visitors. Differences in corolla colour among populations were partially associated with differences in temperature. Our findings suggest that shifts in flower colour of N. glauca across native and invaded ranges could be shaped by changes in both pollination environment and climatic factors. This is the first study on plant invasions considering visual perception of different pollinators and abiotic drivers of flower colour variation.


Subject(s)
Nicotiana , Pollination , Animals , Humans , Color , Plants , Flowers , Birds , Perception
2.
Plant Biol (Stuttg) ; 24(6): 1010-1021, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35975653

ABSTRACT

The idea that a syndrome of floral traits predicts pollination by a particular functional group of pollinators remains simultaneously controversial and widely used because it allows plants to be rapidly assigned to pollinators. To test the idea requires demonstrating that there is an association between floral traits and pollinator type. I conducted such a test in the Cape Floristic Region of South Africa, by studying the pollination of eight plant species from six families that flower in spring and have scentless, actinomorphic, upwards-facing flowers, with orbicular petals all held in the same plane. The petals are brilliant-white with red-purple nectar guides. The tubes are short and hold small volumes of concentrated nectar, except in the rewardless Disa fasciata (Orchidaceae). Pollinators were photographed and captured, pollen loads were analysed and pollination networks were constructed. Consistent with the pollination syndrome hypothesis, the species with the defined syndrome shared a small group of pollinators. The most frequent pollinators belonged to a clade of four tangle-veined fly species with relatively short proboscises (Nemestrinidae: Prosoeca s.s.), while functionally similar Bombyliidae and Tabanidae played minor roles. Among the four Prosoeca species, only Prosoeca westermanni has been described, a result that highlights our ignorance about pollinators. The demonstration of an association between the syndrome of traits and pollination by this group of flies explains the repeated evolution of the syndrome across multiple plant families, and allows prediction of pollinators in additional species. More generally, the result validates the idea that the traits of organisms determine their ecology.


Subject(s)
Diptera , Orchidaceae , Animals , Flowers , Plant Nectar , Plants , Pollination
3.
Plant Biol (Stuttg) ; 22(5): 924-931, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32544265

ABSTRACT

The large body of work on the adaptation of plants to pollinators is still somewhat incomplete because most studies focus on one-to-one interactions. How will adaptation proceed in a multi-pollinator environment? According to Stebbins' Most Effective Pollinator Principle, 'the characteristics of the flower will be moulded by those pollinators that visit it most frequently and effectively.' To test this hypothesis, we studied the pollination biology of Pelargonium incrassatum (Geraniaceae) in the Namaqualand Region of Southern Africa. This species has a long floral tube and we expected its most important pollinator to have a long proboscis. Contrary to expectations, the most important pollinator was a short proboscid fly (a new species of Prosoeca), while Prosoeca peringueyi, which had a proboscis that matched the floral tube length, was a rare visitor. Consistent with the high degree of trait mismatching, we did not detect selection on tube length at most sites. The paradox of mismatching traits can be resolved by considering the strength of the trade-off involved. Adaptation to the rare species can apparently occur without incurring the cost of reduced pollination by the abundant species. Generally, species may often evolve specialized morphology if they do not incur the cost of ecological specialization.


Subject(s)
Diptera , Flowers , Plants , Pollination , Animals , Diptera/anatomy & histology , Flowers/anatomy & histology , Phenotype , Plants/anatomy & histology
4.
Plant Biol (Stuttg) ; 20 Suppl 1: 224-230, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28960844

ABSTRACT

Interactions among plant species via pollinators vary from competitive to mutualistic and can influence the probability of stable coexistence of plant species. We aimed to determine the nature of the interaction via flower visitors between Leucospermum conocarpodendron and Mimetes fimbriifolius, two shrubs in the Proteaceae that share many ecological traits and coexist on the Cape Peninsula, South Africa. To assess the extent of pollinator sharing we analysed nectar properties and recorded the pollinator fauna, their behaviour and contribution to seed set. To test for competition via interspecific pollen transfer, we recorded the movement patterns of pollinators and quantified pollen loads. To determine the effect of co-flowering on visitation rates we recorded visits in stands that varied in the density of the two species. We found that the species produce similar rewards and share pollinating Cape Sugarbirds (Promerops cafer). Interspecific pollen transfer is avoided by placing pollen on different parts of the bird. Both species are visited by nectar-thieving Orange-breasted Sunbirds (Anthobaphes violacea). Insects and autonomous self-pollination contributed little to seed set. Pollinator visits increased with conspecific density in both species, and the slope of the increase was steepest in the presence of high densities of the co-occurring plant species. Nectar thief visits also increased with conspecific density in both species, but the slope declined with increasing density of the co-occurring species. Co-occurrence enhanced pollinator visits and alleviated nectar robbing in both plant species, consistent with mutualisms. Mutualism within a trophic level is unusual, but may help to explain the stable coexistence of ecologically similar species.


Subject(s)
Birds/physiology , Proteaceae/physiology , Symbiosis , Animals , Climate , Ecosystem , Insecta/physiology , Plant Nectar/physiology , Pollination/physiology , South Africa
5.
J Evol Biol ; 29(8): 1631-42, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27206242

ABSTRACT

Mating patterns and natural selection play important roles in determining whether genetic polymorphisms are maintained or lost. Here, we document an atypical population of Lapeirousia anceps (Iridaceae) with a bimodal distribution of floral-tube length and investigate the reproductive mechanisms associated with this pattern of variation. Flowers were visited exclusively by the long-proboscid fly Moegistorhynchus longirostris (Nemestrinidae), which exhibited a unimodal distribution of proboscis length and displayed a preference for long-tubed phenotypes. Despite being visited by a single pollinator species, allozyme markers revealed significant genetic differentiation between open-pollinated progeny of long- and short-tubed phenotypes suggesting mating barriers between them. We obtained direct evidence for mating barriers between the floral-tube phenotypes through observations of pollinator foraging, controlled hand pollinations and measurements of pollen competition and seed set. Intermediate tube-length phenotypes produced fewer seeds in the field than either long- or short-tubed phenotypes. Although floral-tube length bimodality may not be a stable state over long timescales, reproductive barriers to mating and low 'hybrid' fitness have the potential to contribute to the maintenance of this state in the short term.


Subject(s)
Genetic Fitness , Iridaceae/physiology , Pollination , Animals , Flowers , Iridaceae/growth & development , Reproduction , Selection, Genetic
6.
Oncogene ; 35(10): 1324-7, 2016 Mar 10.
Article in English | MEDLINE | ID: mdl-26028024

ABSTRACT

BRCA1 and BRCA2 are the two major genes predisposing to breast and ovarian cancer. Whereas high de novo mutation rates have been demonstrated for several genes, only 11 cases of de novo BRCA1/2 mutations have been reported to date and the BRCA1/2 de novo mutation rate remains unknown. The present study was designed to fill this gap based on a series of 12 805 consecutive unrelated patients diagnosed with breast and/or ovarian cancer who met the inclusion criteria for BRCA1/2 gene analysis according to French guidelines. BRCA1/2 mutations were detected in 1527 (12%) patients, and three BRCA1 mutations and one BRCA2 mutation were de novo. The BRCA1/2 de novo mutation rate was estimated to be 0.3% (0.1%; 0.7%). Although rare, it may be useful to take the possibility of de novo BRCA1/2 mutation into account in genetic counseling of relatives and to improve the understanding of complex family histories of breast and ovarian cancers.


Subject(s)
Breast Neoplasms/genetics , Genes, BRCA1 , Genes, BRCA2 , Genetic Predisposition to Disease/genetics , Mutation , Ovarian Neoplasms/genetics , Female , Humans , Middle Aged
7.
Acta Clin Belg ; 70(2): 121-3, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25331621

ABSTRACT

The association of miconazole and oral anticoagulants should be carried out with great caution because of potentially serious side effects. This phenomenon is well known in the case of systemic administration of miconazole, but there is limited awareness that also topical oral administration of miconazole can provoke these effects. In this paper we describe four patients followed at the Cardiology Department of the Ghent University Hospital, who used an oral mucosal miconazole preparation, and who developed an increased international normalized ratio.


Subject(s)
Anticoagulants/administration & dosage , Antifungal Agents/administration & dosage , Miconazole/administration & dosage , Administration, Oral , Administration, Topical , Aged , Aged, 80 and over , Anticoagulants/adverse effects , Antifungal Agents/adverse effects , Drug Interactions , Female , Hemorrhage/chemically induced , Humans , International Normalized Ratio , Miconazole/adverse effects , Middle Aged , Warfarin/administration & dosage
8.
J Genet Couns ; 22(6): 844-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23689926

ABSTRACT

The profession of genetic counseling in France was recognized in 2004, based on the recommendations of a mandate commissioned by the Health Minister to explore the medical demographics of France. The report predicted a shortage of health professionals in the field of genetics, particularly in light of the rapid development of molecular testing. Development of the profession was supported by a legal framework, and today 107 genetic counselors have graduated from the specific educational program which awards the Professional Master's Degree of Human Pathology, entitled Master in Genetic Counseling and Predictive Medicine. Here we will trace the development of the profession in France and review the demographic characteristics of the students and genetic counselors practicing the profession today.


Subject(s)
Career Choice , Genetic Counseling , Curriculum , Education, Professional/organization & administration , France
10.
Fam Cancer ; 9(4): 663-7, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20842456

ABSTRACT

Uveal melanoma arises from melanocytes of the uveal tract (iris, ciliary body and choroid) and represents the most common intraocular malignancy in adults. Some rare clinical situations (young age at diagnosis, bilateral or multifocal forms, association with cutaneous malignant melanoma and/or familial aggregations of melanomas) are suggestive of genetic susceptibility. The aim of this study was to evaluate the contribution of CDKN2A/P16INK4A, P14ARF and CDK4 gene germline mutations in a series of patients with uveal melanoma recruited in a single institution with a clinical presentation indicative of genetic predisposition. Molecular analyses were proposed to 36 patients and were performed in 25 cases. The contribution of BRCA1/2 gene germline mutations in patients with uveal melanoma and a personal and/or family history of breast/ovarian cancers was also evaluated. Molecular analysis of BRCA1/2 genes was proposed to 35 patients and was performed in 25 patients. No deleterious germline mutation was identified in either group of patients. These results indicate that the CDKN2A/P16INK4A, P14ARF, CDK4 genes are not responsible for the vast majority of genetic susceptibility to uveal melanoma. They also suggest that one case of uveal melanoma in a family with a history of breast cancer is not sufficient to justify BRCA1/2 genetic testing when the classical criteria for molecular analysis are not present. International studies are ongoing in melanoma-prone families in an attempt to identify uveal melanoma susceptibility loci and genes.


Subject(s)
Cyclin-Dependent Kinase 4/genetics , Cyclin-Dependent Kinase Inhibitor p16/genetics , Genetic Predisposition to Disease , Germ-Line Mutation/genetics , Melanoma/genetics , Tumor Suppressor Protein p14ARF/genetics , Uveal Neoplasms/genetics , Adolescent , Adult , Aged , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , DNA, Neoplasm/genetics , Female , Genetic Testing , Humans , Male , Melanoma/pathology , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Pedigree , Polymerase Chain Reaction , Prognosis , Uveal Neoplasms/pathology , Young Adult
11.
Bull Cancer ; 96(10): 979-88, 2009 Oct.
Article in French | MEDLINE | ID: mdl-19744918

ABSTRACT

Several risk estimation models for breast or ovarian cancers have been developed these last decades. All these models take into account the family history, with different levels of sophistication. Gail model was developed in 1989 taking into account the family history (0, 1 or > or = 2 affected relatives) and several environmental factors. In 1990, Claus model was the first to integrate explicit assumptions about genetic effects, assuming a single gene dominantly inherited occurring with a low frequency in the population. BRCAPRO model, posterior to the identification of BRCA1 and BRCA2, assumes a restricted transmission with only these two dominantly inherited genes. BOADICEA model adds the effect of a polygenic component to the effect of BRCA1 and BRCA2 to explain the residual clustering of breast cancer. At last, IBIS model assumes a third dominantly inherited gene to explain this residual clustering. Moreover, this model incorporates environmental factors. We applied the Claus, BRCAPRO, BOADICEA and IBIS models to four clinical situations, corresponding to more or less heavy family histories, in order to study the consistency of the risk estimates. The three more recent models (BRCAPRO, BOADICEA and IBIS) gave the closer estimations. These estimates could be useful in clinical practice in front of complex analysis of breast and/or ovarian cancers family history.


Subject(s)
Breast Neoplasms/genetics , Family Health , Models, Genetic , Age Factors , Female , Genes, BRCA1 , Genes, BRCA2 , Genetic Predisposition to Disease/genetics , Humans , Multigene Family , Mutation/genetics , Ovarian Neoplasms/genetics , Risk Assessment/methods , Risk Factors
12.
Gynecol Oncol ; 91(1): 32-8, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14529659

ABSTRACT

OBJECTIVE: This phase II study was performed to evaluate the activity and toxicity of gemcitabine plus cisplatin as first-line treatment of advanced epithelial ovarian cancer. METHODS: Chemonaive patients with histologically or cytologically confirmed FIGO stage III or IV epithelial ovarian carcinoma were enrolled. Patients received cisplatin 75 mg/m(2) on Day 1 and gemcitabine 1250 mg/m(2) on Days 1 (after cisplatin) and 8 of a 21-day cycle. RESULTS: Of the 42 female patients (median age 60 years) enrolled, 81% had a Zubrod performance status of 0 or 1. Among the 37 response-evaluable patients, there were 5 (13.5%) pathological complete responses (CRs), 16 (43.2%) pathological partial responses (PRs), and 3 (8.1%) clinical PRs, for an overall response rate of 64.9% (95% CI: 47.4-79.8%) and a pathological response rate of 56.8%. Per an intent-to-treat analysis, the overall response rate was 57.1% (95% CI: 41.0-72.3%). After a median follow-up time of 15.8 months, the median survival was 24.0 months and median progression-free survival was 13.4 months. Grade 3/4 neutropenia and thrombocytopenia occurred in 69.0 and 33.3% of patients, respectively, with no febrile neutropenia or hemorrhage. Grade 3/4 nausea and vomiting occurred in 35.7% and grade 3 alopecia in 21.4% of the patients. One patient died due to a toxicity-related death (dyspnea). CONCLUSIONS: Gemcitabine plus cisplatin is active and feasible as first-line treatment of advanced epithelial ovarian cancer. Further clinical trials adding gemcitabine to first-line treatment seem warranted.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Deoxycytidine/analogs & derivatives , Ovarian Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/administration & dosage , Cisplatin/adverse effects , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Disease-Free Survival , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Middle Aged , Survival Rate , Gemcitabine
14.
Clin Neurol Neurosurg ; 104(4): 345-51, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12140103

ABSTRACT

OBJECTIVES: (1) To determine the prevalence of swallowing problems in MS patients and its relation to the overall disability. (2) To define the most frequent symptoms suggestive of dysphagia. (3) To describe the abnormalities on manofluoroscopy (MFS). METHODS: Three hundred and eight consecutive MS patients were asked whether they ever had swallowing problems. If so the questionnaire of the Johns Hopkins Swallowing Centre was applied to qualify the dysphagia. A MFS was performed in 30 patients with dysphagia covering the entire spectrum of MS. Overall disability was assessed using the Expanded Disability Status Scale (EDSS). RESULTS: Seventy-three of our 309 patients had permanent dysphagia (24%). Another 5% had a history of transitory swallowing problems only. Permanent dysphagia started to be a problem in mildly impaired patients (EDSS 2-3). Prevalence increased together with rising disability to reach 65% in the most severely disabled subjects (EDSS 8-9). Two alarming symptoms of patients with swallowing problems, coughing or choking during the meal and a history of pneumonia were present in 59%, respectively, 12% of these patients. MFS showed deficiency of the oral phase in all patients, while only the patients with an EDSS higher than 7.5 showed abnormalities of the pharyngeal phase. CONCLUSIONS: Permanent dysphagia may already develop in mildly impaired MS patients but becomes a rather frequent finding in MS patients with moderate or severe disability. MFS is a sensitive and useful ancillary examination. Important qualitative changes of the pharyngeal phase on MFS are seen in patients with an EDSS higher than 7.5.


Subject(s)
Deglutition Disorders/etiology , Disabled Persons , Multiple Sclerosis/complications , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Deglutition Disorders/epidemiology , Female , Humans , Male , Middle Aged , Prevalence , Severity of Illness Index
15.
Acta Clin Belg ; 57(6): 325-30, 2002.
Article in English | MEDLINE | ID: mdl-12723250

ABSTRACT

D-dimers (DD), specific degradation products of crosslinked fibrin, are markers for activation of plasma coagulation and/or fibrinolysis. DD results below the cut-off level are proven to be useful to rule out the probable diagnosis of deep venous thrombosis (DVT) and/or pulmonary embolism (PE). Our objective was to demonstrate that positive DD occur in many diseases and certain physiological conditions as high age and pregnancy and to look for gradations in positivity between different pathological conditions. We wanted to investigate the request attitude of our clinicians concerning DD. Positive DD results still confuse some physicians. Retrospectively, we examined medical records of 574 consecutive patients, in whom plasma DD were measured in daily routine. Both outpatients (n = 423) and inpatients (n = 151) were included. We noted their clinically predominant disease. Measurement of DD concentration is too often requested by clinicians, in any medical condition, and is not always clinically relevant. The relation of a positive result and the clinical problem is sometimes not understood. Overall, we found 64% DD positivity with a median concentration of 775 micrograms/L. We found elevated DD concentrations in various clinical conditions.


Subject(s)
Fibrin Fibrinogen Degradation Products/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/analysis , Child , Child, Preschool , Female , Health Services Misuse , Humans , Infant , Male , Middle Aged
16.
Am J Bot ; 88(10): 1768-73, 2001 Oct.
Article in English | MEDLINE | ID: mdl-21669608

ABSTRACT

Field studies in the semiarid Succulent Karoo region of South Africa showed that flowers of Massonia depressa (Hyacinthaceae) are visited at night by at least four rodent species, including two gerbil species. Live-trapped rodents were found to carry Massonia pollen on their snouts; they also had large quantities of Massonia pollen in their feces as a result of grooming their fur. Visits by insects to the flowers were infrequent at one site and apparently absent at another site. Plants enclosed in large-mesh wire cages, which excluded rodents but not insects, set very few seeds relative to open controls. Our initial hypothesis of rodent-pollination in M. depressa was based on the striking similarity of its flowers to those of unrelated, rodent-pollinated Protea species. Convergent traits include dull-colored and very robust flowers situated at ground level, a strong yeasty odor, and secretion of copious amounts of sucrose-dominant nectar during the evening when rodents are active. Despite having a low sugar concentration (∼20%), the nectar of M. depressa is almost 400 times as viscous as an equivalent sugar solution. The jelly-like constituent in the nectar may discourage robbing by insects, while also facilitating lapping by rodents. Our findings illustrate the utility of floral syndromes for generating testable predictions about pollination systems.

17.
Virchows Arch ; 432(2): 119-22, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9504855

ABSTRACT

Adenomyoepithelioma is a mixed epithelial and myoepithelial tumour. In rare cases adenomyoepitheliomas give rise to carcinomas with epithelial, myoepithelial, or mixed epithelial and myoepithelial differentiation. Carcinomas arising in adenomyoepithelioma range from low grade to high grade, and 15 cases have been reported in the literature. We describe a 36-year-old woman with a very rare adenoid cystic carcinoma arising in a tubular adenomyoepithelioma. The histogenesis of carcinoma arising in an adenomyoepithelioma is discussed.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Adenoid Cystic/pathology , Neoplasms, Second Primary/pathology , Adult , Female , Humans
18.
Urol Radiol ; 4(1): 29-31, 1982.
Article in English | MEDLINE | ID: mdl-7101600

ABSTRACT

A case of perirenal lymphatic cysts demonstrated by computed tomography is reported. These lymphatic cysts, a histological subtype of lymphangiomata, are clearly visible as collections with clear fluid-type density surrounding both kidneys. The retroperitoneal localization of this rarity has been reported in the radiological literature, whereas, to our knowledge, the radiological demonstration of the perirenal localization has not. CT provides a unique method for direct radiological visualization of the cyst.


Subject(s)
Cysts/diagnostic imaging , Kidney/diagnostic imaging , Lymph , Tomography, X-Ray Computed , Adult , Humans , Male , Retroperitoneal Space
20.
J Urol ; 116(4): 519-21, 1976 Oct.
Article in English | MEDLINE | ID: mdl-95619

ABSTRACT

The thirty-second case of leiomyosarcoma of the inferior vena cava and the twelfth resectable patient in the series is presented. A review of the literature demonstrates a marked female preponderance (5 to 1). The most common presenting symptom is right abdominal pain and a palpable mass. The different surgical problems generated by the involved segment of the cava are discussed. Noteworthy is the high incidence of Budd-Chiari syndrome owing to hepatic vein obstruction with involvement of the upper third of the cava in the postmortem cases. An argument is developed for debulking the tumor for palliation when it is not completely removable.


Subject(s)
Leiomyosarcoma/diagnostic imaging , Neoplasms/diagnostic imaging , Vena Cava, Inferior , Humans , Leiomyosarcoma/surgery , Male , Middle Aged , Neoplasms/surgery , Palliative Care , Sex Factors , Urography , Vascular Diseases/diagnostic imaging , Vascular Diseases/surgery
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