Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 152
Filter
1.
Ann Bot ; 2023 Jul 05.
Article in English | MEDLINE | ID: mdl-37407025

ABSTRACT

BACKGROUND AND AIMS: Is the increase in species diversity patterns towards lower latitudes, linked to reproductive traits? Plant reproductive organs influence reproductive isolation and hence species divergence. Abiotic differences between temperate and tropical regions can also directly impact on plant reproductive traits. Here we provide a novel overview of southern hemisphere, Afromontane forest tree taxonomical patterns and ask whether reproductive traits relate to latitude, while accounting for environmental (tree height) and evolutionary (biogeographical affinity) selective forces. METHODS: We compiled a novel dataset with a) flower colour, size and pollination syndrome and b) fruit colour, size and dispersal syndrome for 331 tree species found in six Afromontane forest regions. We categorised each species into latitudinal distribution using these six regions, spanning the southern Cape (34º S) to Mount Kenya (0º S). Additionally, we gathered maximum tree height (m) for each species and determined the global distribution of all 196 tree genera (Afrotropical, Palaeotropical or Pantropical). KEY RESULTS: Species, genera and families showed a general decrease in richness away from tropical and subtropical forests towards warm temperate forests. Southern Afrotemperate forests (the furthest south) had the highest tree endemism. There was no relationship between latitude and the reproductive traits tested here. Biogeographical affinity related to fruit colour and dispersal syndrome, with palaeotropical genera showing relative increases in black-purple fruit colour compared to pantropical genera and palaeotropical genera showing relative increases in biotic seed dispersal compared to Afrotropical genera, which showed higher relative abiotic seed dispersal. Taller trees had a higher chance to be wind or insect pollinated (compared to bird pollinated) and had larger fruits. CONCLUSIONS: Latitude explained patterns in Afromontane tree taxonomical diversity, however tree reproductive traits did not relate to latitude. We suggest that phylogenetic conservatism or convergence, or both, explain the reported patterns.

2.
Plant Biol (Stuttg) ; 23(6): 915-922, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34396663

ABSTRACT

Invasive alien plants often influence pollinator visitation to native plants when sharing pollinator guilds. It is of conservation concern when the invasive alien plant is characterized by floral resources that attract pollinators, thereby reducing the reproductive success of native species. This is well studied for insects, but whether the same is true for bird pollinators is largely unknown. We address this by considering the impact of an invasive alien plant (Banksia speciosa) on visitation rates of nectar-feeding bird pollinators to native Protea compacta in the Cape Floristic Region of South Africa. We determined bird pollinator visitation rate to B. speciosa and P. compacta over 21 h of observation at three sites. We also quantified how visitation rate influenced reproductive success of both study species through different breeding experiments. Sugarbird visitation to P. compacta was significantly lower in the presence of B. speciosa, while there was no effect for sunbirds as they mostly avoided B. speciosa. Protea compacta had higher nectar volumes and sucrose per flower than B. speciosa. Sucrose per hectare was higher in all P. compacta plots compared to B. speciosa. Neither study species is pollen limited and they are self-compatible to some extent. But pollinator visitation enhanced seed production in both species. We show here that the invasive alien B. speciosa flowers attract sugarbirds - but not sunbirds - away from native P. compacta. The long-term effect of reduced pollinator visitation may reduce the fitness of P. compacta, but the long-term demographic impact is unknown and would require further study.


Subject(s)
Passeriformes , Proteaceae , Animals , Flowers , Introduced Species , Plant Breeding , Plant Nectar , Pollination
3.
Rev Med Liege ; 76(2): 111-116, 2021 Feb.
Article in French | MEDLINE | ID: mdl-33543857

ABSTRACT

Dental caries still affect 60 to 90 % of children attending school worldwide. We collected epidemiological data from 212 children under the age of 6 supervised by the Office of Birth and Childhood in the Province of Liège. We analyzed the relationships between the prevalence of dental caries in the studied population sample and the risk factors that are usually associated to dental carries. Among the 212 examined children, 66 % had neither decayed nor filled teeth, 10.4 % had one decayed or filled teeth, and 23.6 % had at least 2 decayed or filled teeth. The prevalence of carious disease increases with age, ranging from 33 % for 3-year children to 44 % for 4-year children and to 59 % for 5-year children. Moreover, the number of decayed or filled teeth is significantly higher for children who brush their teeth alone, without the help of parents, and for those who consume frequently sweet snacks and drinks. Finally, the socio-economic condition also influences dental health of very young children.


La carie dentaire touche encore 60 à 90 % des enfants scolarisés dans le monde. Nous avons collecté les données épidémiologiques de 212 d'enfants de moins de 6 ans fréquentant l'Office de la Naissance et de l'Enfance en Province de Liège. Les relations entre la prévalence de la carie dentaire dans l'échantillon de population étudié et les facteurs de risque ont été analysées. Parmi les 212 enfants examinés, 66 % n'ont aucune dent cariée ou obturée, 10,4 % ont une dent cariée ou obturée et 23,6 % ont au moins 2 dents cariées ou obturées. La prévalence de la maladie carieuse augmente avec l'âge passant de 33 % chez les enfants de 3 ans à 44 % chez les enfants de 4 ans et 59 % chez ceux de 5 ans. De plus, le nombre de dents cariées ou obturées est significativement plus élevé chez les enfants qui se brossent les dents seuls, sans l'aide d'un parent, ou encore chez ceux qui consomment plus fréquemment des boissons ou des collations sucrées. Enfin, le facteur socio-économique influence également la santé dentaire des très jeunes enfants.


Subject(s)
Dental Caries , Child , Child, Preschool , Dental Caries/epidemiology , Humans , Oral Health , Pilot Projects , Prevalence , Risk Factors
4.
Biomed Res Int ; 2016: 4741516, 2016.
Article in English | MEDLINE | ID: mdl-27376084

ABSTRACT

Objective. Nd:YAP laser has several potentialities of clinical applications in endodontics. The aim of our study is to determine the safety range of irradiation parameters during endodontic application of Nd:YAP laser that can be used without damaging and overheating the periodontal tissue. Material and Methods. Twenty-seven caries-free single-rooted extracted human teeth were used. Crowns were sectioned to obtain 11 mm root canal length. Temperature increases at root surfaces were measured by a thermocouple during Nd:YAP laser irradiation of root canals at different energy densities. Canal irradiation was accomplished with a circular and retrograde movement from the apex until the cervical part of the canal during 10 seconds with an axial speed of 1 mm/s. Each irradiation was done in a canal irrigated continuously with 2.25% NaOCl solution. Results. Periodontal temperature increase depends on the value of energy density. Means and standard deviations of temperature increases at root surfaces were below 10°C (safe threshold level) when the average energy densities delivered per second were equal to or below 4981 J/cm(2) and 9554 J/cm(2), respectively, for irradiations using a fiber diameter of 320 µm and 200 µm. Conclusions. Within the limitations of this study and under specific irradiation conditions, Nd:YAP laser beam may be considered harmless for periodontal tissues during endodontic applications.


Subject(s)
Dental Caries/therapy , Lasers, Solid-State , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Safety , Endodontics , Female , Humans , Male
5.
Plant Biol (Stuttg) ; 18(6): 1048-1052, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27219484

ABSTRACT

Pollinator specialisation through exploitation barriers (such as long floral tubes) does not necessarily mean a lack of pollination when the favoured pollinator is rare or absent. Theory predicts that suboptimal visitors will contribute to plant reproduction in the absence of the most effective pollinator. Here I address these questions with Chasmanthe floribunda a long-tubed plant species in the Cape Floristic Region, which is reliant on one species of pollinator, the long-billed Malachite Sunbird. In contrast to short-billed sunbirds, the Malachite Sunbird occurs in lower abundance or is absent in transformed landscapes. Short-billed sunbirds rob and thieve nectar from long-tubed flowers, but their potential contribution towards pollination is unknown. Experiments assessing seed set after single flower visits were performed to determine whether thieving short-billed sunbirds can act as substitute pollinators. To determine whether short-billed sunbirds reduce pollen limitation in transformed areas, pollen supplementation was done by hand and compared to natural fruit set. Short billed sunbirds are unable to act as substitute pollinators, and seed set is significantly lower in the flowers that they visited, compared to flowers visited by long-billed sunbirds. This is substantiated on a landscape scale, where fruit production in Chasmanthe floribunda could artificially be increased by 35% in transformed landscapes, but not so in natural areas. These findings have important consequences for the management and conservation of long-tubed bird-pollinated plant species that exist in recently transformed landscapes. The potential vulnerability of specialised plant species in transformed landscapes is highlighted.


Subject(s)
Iridaceae/physiology , Passeriformes/physiology , Pollination , Animals , Flowers/anatomy & histology , Flowers/physiology , Iridaceae/anatomy & histology , Plant Nectar/physiology , Pollen/anatomy & histology , Pollen/physiology , Reproduction , Seeds/anatomy & histology , Seeds/physiology
6.
Plant Biol (Stuttg) ; 18(1): 124-31, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25865269

ABSTRACT

Reproduction is a crucial stage in the naturalisation of introduced plant species. Here, using breeding system experiments and observations of floral visitors, we investigate whether a lack of pollinators or an inability to autonomously self-fertilise limits naturalisation in five Australian Banksia species and the co-familial Hakea salicifolia in South Africa. Banksia species were heavily utilised by native insects and nectar-feeding birds. Although Banksia produced fruit when pollinators were excluded, pollinators significantly increased seed set in four of the five species. H. salicifolia flowers were visited by 11 insect species; honeybees (Apis mellifera) were the main visitors. Flowers in naturalised H. salicifolia populations received almost four times the number of visits as flowers in non-naturalised populations; the latter showed both pollen limitation (PLI 0.40) and partial self-incompatibility. This should not prevent invasion, since H. salicifolia produces fruits via autonomous selfing in the absence of pollinators. The results suggest a limited role of breeding systems in mediating naturalisation of introduced Proteaceae species. Other factors, such as features of the recipient environments, appear to be more important. Spatial variation in rates of reproduction might, however, explain variation in the extent and rate of naturalisation of different populations.


Subject(s)
Pollination/physiology , Proteaceae/physiology , Self-Fertilization/physiology , Animals , Australia , Bees , Flowers/physiology , Insecta , Introduced Species , Pollen , Seeds/growth & development , South Africa
7.
Rev Med Liege ; 71(12): 567-572, 2016 Dec.
Article in French | MEDLINE | ID: mdl-28387098

ABSTRACT

Preserving primary teeth is crucial for maintaining the maxillary growth, aesthetics, mastication, and speech and for preventing from abnormal habits. Given the peculiar anatomy of the primary tooth, caries grow faster and more frequently to the pulp. In pediatric dentistry, new methods and enhanced material have been recently released on the market and broadened the field of treatments. In this paper, we review the pulp diseases affecting children and focus on the current root canal therapies that favour the physiological primary tooth loss.


Conserver les dents de lait est essentiel pour assurer la croissance des maxillaires, l'esthétique, la mastication et la phonation ainsi que pour prévenir l'apparition de dysfonctions. Vu les particularités anatomiques des dents de lait, la carie progresse toujours plus rapidement et plus fréquemment jusqu'à la pulpe. L'avènement de nouvelles techniques et de nouveaux matériaux en dentisterie pédiatrique a élargi nos possibilités thérapeutiques. De même, l'interdiction d'utilisation de certains produits a conduit le pédodontiste à devoir trouver des alternatives de traitement. Le but de cet article est de faire le point sur les pathologies pulpaires chez l'enfant et sur les thérapeutiques endocanalaires actuelles.


Subject(s)
Dental Pulp Diseases/therapy , Tooth, Deciduous/pathology , Child , Dental Pulp/pathology , Dental Pulp Diseases/pathology , Dental Pulp Diseases/surgery , Humans
9.
Water Sci Technol ; 71(4): 487-94, 2015.
Article in English | MEDLINE | ID: mdl-25746638

ABSTRACT

To date, phosphorus recovery as struvite in wastewater treatment plants has been mainly implemented on water phases resulting from dewatering processes of the sludge line. However, it is possible to recover struvite directly from sludge phases. Besides minimising the return loads of phosphorus from the sludge line to the water line, placing such a process within the sludge line is claimed to offer advantages such as a higher recovery potential, enhanced dewaterability of the treated sludge, and reduced speed of scaling in pipes and dewatering devices. In the wastewater treatment plant at Leuven (Belgium), a full-scale struvite recovery process from digested sludge has been tested for 1 year. Several monitoring campaigns and experiments provided indications of the efficiency of the process for recovery. The load of phosphorus from the sludge line returning to the water line as centrate accounted for 15% of the P-load of the plant in the reference situation. Data indicated that the process divides this phosphorus load by two. An improved dewaterability of 1.5% of dry solids content was achieved, provided a proper tuning of the installation. Quality analyses showed that the formed struvite was quite pure.


Subject(s)
Phosphorus/chemistry , Sewage/chemistry , Waste Disposal, Fluid/methods , Wastewater/chemistry , Water Pollutants, Chemical/chemistry , Belgium , Bioreactors , Water Purification/methods
10.
Vet Rec ; 166(24): 753-6, 2010 Jun 12.
Article in English | MEDLINE | ID: mdl-20543166

ABSTRACT

Thirty-five serum samples and six hygroma fluid samples were collected from sexually mature cattle in one herd with clinical signs of brucellosis (abortion and hygromas) in the Western Region of the Gambia in order to isolate and characterise Brucella species. Information on the sex, age, number of calvings, number of abortions, presence of hygromas, and presence of orchitis was also collected for each animal sampled. Twenty-six (74 per cent) of the serum samples were positive in the rose bengal test and 29 (83 per cent) were positive by indirect ELISA. Three isolates of Brucella, biotyped as Brucella abortus biovar 3, were cultured from six hygroma fluid samples. The multiple locus variable number tandem repeat analysis assay clustered the isolates as B abortus with the same profile for the three isolates, suggesting a common origin of contamination.


Subject(s)
Brucella abortus/isolation & purification , Brucella/classification , Brucellosis, Bovine/microbiology , Animals , Bacterial Typing Techniques , Brucella/genetics , Cattle , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Gambia , Genotype , Phenotype , Rose Bengal
11.
Parasite Immunol ; 32(6): 399-405, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20500670

ABSTRACT

TSOL18 is a recombinant protein that has been shown in repeated experimental trials to be capable of protecting pigs against challenge infection with the cestode parasite Taenia solium. Antibodies raised by the vaccine are capable of killing the parasite in an in vitro culture and it is believed that antibody and complement-mediated killing of invading parasites is the major protective immune mechanism induced by vaccination with TSOL18. Investigations were undertaken to characterize whether the principal antibody specificities raised by TSOL18 in pigs were against linear or conformational determinants. TSOL18 was expressed in two truncated forms representing either the amino terminal portion or the carboxy terminal portion, with the two truncations overlapping in sequence by 25 amino acids. The original protein (designated TSOL18N(-)) and the two truncations (TSOL18N(-)-1 and TSOL18N(-)-2) were used in inhibition ELISA. TSOL18N(-) was shown to be capable of completely inhibiting the binding of pig anti-TSOL18N(-) antibodies to TSOL18N(-) in ELISA. However, neither TSOL18N(-)-1 nor TSOL18N(-)-2, either alone or when combined together, was capable of inhibiting any detectable amount of reactivity of pig anti-TSOL18N(-) antibodies with TSOL18N(-). It is concluded that the dominant antibody specificities, and probably the host-protective specificities, of TSOL18 are conformational epitopes.


Subject(s)
Antibodies, Helminth/blood , Antigens, Helminth/immunology , Epitope Mapping , Epitopes, B-Lymphocyte/immunology , Taenia solium/immunology , Animals , Antigens, Helminth/chemistry , Antigens, Helminth/genetics , Enzyme-Linked Immunosorbent Assay/methods , Epitopes, B-Lymphocyte/chemistry , Epitopes, B-Lymphocyte/genetics , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/immunology , Protein Conformation , Sequence Deletion , Swine
12.
Neurology ; 74(11): 909-12, 2010 Mar 16.
Article in English | MEDLINE | ID: mdl-20231667

ABSTRACT

BACKGROUND: Rett syndrome (RTT) is a neurodevelopmental disorder primarily seen in females, most with a mutation in MECP2. Epilepsy has been reported in 50%-80%. Previous reports were based on small sample sizes or parent-completed questionnaires, or failed to consider the impact of specific MECP2 mutations. METHODS: The Rare Disease Consortium Research Network for RTT is an NIH-funded project to characterize the clinical spectrum and natural history of RTT in advance of clinical trials. Evaluations include clinical status (classic vs atypical RTT), MECP2 mutations, clinical severity, and presence, frequency, and treatment of seizures. RESULTS: Enrollment as of June 2008 is 602; 528 (88%) meet clinical criteria for classic RTT. Of these, 493 (93%) have MECP2 mutations. Age range was 8 months to 64 years. A total of 360 (60%) were reported to have seizures, including 315 (60%) classic and 45 (61%) atypical RTT. Physician assessment of the 602 indicated that 48% had seizures. There was no significant difference in seizure occurrence by race/ethnicity. A significant age impact for seizures was seen and seizures were infrequent before age 2 years. MECP2 mutations most frequently associated with epilepsy were T158M (74%) and R106W (78%), and less frequently R255X and R306C (both 49%). Individuals with seizures had greater overall clinical severity, and greater impairment of ambulation, hand use, and communication. DISCUSSION: Seizures are common in Rett syndrome, have an age-related onset and occurrence, vary by mutation, and are associated with greater clinical severity. This information represents a key consideration for designing clinical trials.


Subject(s)
Epilepsy/genetics , Rett Syndrome/genetics , Adolescent , Adult , Age Factors , Age of Onset , Child , Child, Preschool , Epilepsy/complications , Female , Genetic Predisposition to Disease , Humans , Infant , Male , Methyl-CpG-Binding Protein 2/genetics , Middle Aged , Phenotype , Regression Analysis , Rett Syndrome/complications , Severity of Illness Index , Sex Factors , Young Adult
13.
J Helminthol ; 84(4): 441-6, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20334716

ABSTRACT

A survey was conducted in 150 households owning 1756 pigs in the rural areas of Mayo-Danay division in the north of Cameroon. A questionnaire survey was carried out to collect information on the pig-farming system and to identify potential risk factors for Taenia solium cysticercosis infection in pigs. Blood samples were collected from 398 pigs with the aim of estimating the seroprevalence of T. solium cysticercosis. The results showed that 90.7% of the pigs are free roaming during the dry season and that 42.7% of households keeping pigs in the rural areas have no latrine facility. Seventy-six per cent of the interviewed pig owners confirmed that members of the household used open-field defecation. Enzyme-linked immunosorbent assay (ELISA) for antigen and antibody detection showed an apparent prevalence of cysticercosis of 24.6% and 32.2%, respectively. A Bayesian approach, using the conditional dependence between the two diagnostic tests, indicated that the true seroprevalence of cysticercosis in Mayo-Danay was 26.6%. Binary logistic regression analysis indicated that a lack of knowledge of the taeniasis-cysticercosis complex and the absence of a pig pen in the household were associated with pig cysticercosis.


Subject(s)
Animal Husbandry/methods , Cysticercosis/veterinary , Cysticercus/immunology , Swine Diseases/epidemiology , Taenia solium/immunology , Animals , Antibodies, Helminth/blood , Antigens, Helminth/analysis , Cameroon/epidemiology , Cysticercosis/diagnosis , Cysticercosis/epidemiology , Cysticercosis/parasitology , Cysticercus/isolation & purification , Enzyme-Linked Immunosorbent Assay , Humans , Prevalence , Risk Factors , Rural Population , Surveys and Questionnaires , Sus scrofa , Swine , Swine Diseases/parasitology , Taenia solium/isolation & purification , Toilet Facilities
14.
Trop Med Int Health ; 15(4): 476-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20180937

ABSTRACT

OBJECTIVE: To determine whether epilepsy is caused by Taenia solium cysticercosis in The Gambia. METHODS: Case-control study testing samples collected from 210 people with epilepsy and 420 matched controls by sex and age +/-5 years from 69 different places around the country during the period October 2008-March 2009. All serum samples were subjected to an antigen detection ELISA (Ag-ELISA) and electro-immunotransfer blot (EITB), and the seropositives were further CT-scanned to determine the presence of cysticerci in the brain. RESULTS: Although not significantly different (P = 0.668), circulating Taenia antigen was found by Ag-ELISA in 1.4% (95% CI: 0.3-4.1) of people with epilepsy and in 1.9% (95% CI: 0.8-3.7) of the controls. A non-significant (P = 0.4718) odds ratio of association 0.75 (95% CI: 0.13-3.15) between epilepsy and the presence of Taenia antigens was found. All 630 serum samples turned out seronegative by the EITB test. There were no intracranial cysts or cyst-like structures detected among the nine CT-scanned Ag-ELISA seropositives. CONCLUSION: Epilepsy appears not to be caused by cysticercosis in The Gambia.


Subject(s)
Epilepsy/parasitology , Neurocysticercosis/complications , Neurocysticercosis/diagnosis , Taenia solium/isolation & purification , Adult , Aged , Animals , Antigens, Helminth/analysis , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Epilepsy/diagnosis , Female , Gambia , Humans , Immunoblotting/methods , Male , Middle Aged , Surveys and Questionnaires , Tomography, X-Ray Computed , Young Adult
15.
Lasers Med Sci ; 25(5): 655-9, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19529881

ABSTRACT

The capacity of photo-sensitizers, used in combination with laser light to kill micro-organisms has been demonstrated in different studies. Photo-activated disinfection (PAD) has been introduced in periodontology as an aid for disinfection of periodontal pockets. The aim of this study is to verify the harm for dental vitality of the use of PAD in periodontal pockets. Root canals of 24 freshly extracted human teeth where prepared using profiles up to a size of ISO #50 and filled with thermo-conductor paste. A silicon-based false gum was made in which a periodontal pocket was created and filled with photo-sensitizer phenothiazine chloride (phenothiazine-5-ium, 3.7-bis (dimethylamino)-, chloride). The external root surface was irradiated during 60 s with a 660-nm diode laser (output power: 20 mW; power density: 0.090 W/cm(2); Energy density: 5.46 J/cm(2)) using a periodontal tip with a diameter of 1 mm and a length of 7 mm. Temperatures were recorded inside the root canal using a thermocouple. Measurements were recorded every second, starting at 10 s before lasering, during the irradiation and were continued for 150 s after the end of irradiation, and six measurements were done per tooth. An average temperature increase of 0.48 +/- 0.11 degrees C was recorded. Our results demonstrated that pulp temperature increase was lower than 3 degrees C, which is considered to be harmless for pulp injury. Regarding pulp temperature increase, the use of PAD for disinfection of periodontal pockets can be considered as a safe procedure for dental vitality.


Subject(s)
Dental Pulp/radiation effects , Disinfection/methods , Low-Level Light Therapy/adverse effects , Periodontal Pocket/radiotherapy , Dental Pulp/injuries , Hot Temperature/adverse effects , Humans , In Vitro Techniques , Lasers, Semiconductor/adverse effects , Periodontal Pocket/microbiology , Photosensitizing Agents/therapeutic use , Safety , Temperature
16.
Lasers Med Sci ; 25(5): 651-4, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19488675

ABSTRACT

Photo-activated decontamination (PAD) has been reported in caries treatment as an aid in dentine decontamination. The aim of this study is to verify the harmlessness for pulp vitality of photo-activated decontamination (PAD) in caries treatment. Twenty freshly extracted single-rooted teeth were used. Deep class I cavities with a

Subject(s)
Dental Caries/radiotherapy , Dental Pulp/radiation effects , Disinfection/methods , Low-Level Light Therapy/adverse effects , Dental Caries/microbiology , Dental Pulp/injuries , Dental Pulp/microbiology , Dentin/microbiology , Dentin/radiation effects , Hot Temperature/adverse effects , Humans , In Vitro Techniques , Lasers, Semiconductor/adverse effects , Photosensitizing Agents/administration & dosage , Safety , Temperature
17.
Vet Parasitol ; 163(1-2): 127-31, 2009 Jul 07.
Article in English | MEDLINE | ID: mdl-19423225

ABSTRACT

The aim of this study was to assess the existence of possible cross-protection between Trypanosoma congolense strains of low and extreme virulence circulating in the same trypanosomiasis focus. Groups of six mice were infected using one of three strains of low virulence and challenged with one of three strains of extreme virulence. A group of six mice was used as control for each strain of low and extreme virulence. The results showed that mice infected with one of the strains of extreme virulence developed high parasitaemia and a significant drop of the PCV compared to mice infected with a strain of low virulence and challenged with one of the strains of extreme virulence. With an exception of one strain of extreme virulence (strain F), the survival time of mice infected with the strains of extreme virulence was shorter compared to mice infected with strains of low virulence and subsequently challenged with a strain of extreme virulence. These results suggest that in an area where trypanosomes of various virulence profiles circulate, livestock infected with T. congolense strains of low virulence can be protected against the adverse effects of extremely virulent T. congolense strains.


Subject(s)
Trypanosoma congolense/immunology , Trypanosoma congolense/pathogenicity , Trypanosomiasis, African/immunology , Trypanosomiasis, African/parasitology , Animals , Mice , Parasitemia , Trypanosoma congolense/classification , Trypanosoma congolense/genetics , Virulence
18.
Rev Med Liege ; 64(11): 587-91, 2009 Nov.
Article in French | MEDLINE | ID: mdl-20069974

ABSTRACT

The limited epidemiological data on dental health in Belgium has led our team to conduct a pilot study in this field. Children, aged from 6 to 12 years old came from two primary schools located in the area of Liège, and were clinically examined for their dental health. The main recorded dental parameters were the number of decayed, missed or filled teeth (epidemiological score DMFT) as well as the amount of dental plaque on the buccal side of the teeth. The results of this study have shown that the prevalence of the teeth decays was in accordance with data from the Worldwide Organization of Health (WHO). However our results have also shown the need to continue dental health prevention. Indeed, some children and their parents enrolled in this pilot study, were found to be not informed about fluoride and its needs in children, oral hygiene practices and the factors that prevented the development of dental caries.


Subject(s)
Dental Caries/epidemiology , Adolescent , Belgium/epidemiology , Child , Female , Humans , Male , Pilot Projects , Prevalence
19.
Lasers Med Sci ; 24(1): 1-5, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18038180

ABSTRACT

In this study, we compared the microleakage of composite fillings cured with halogen bulb, LED and argon ion laser (488 nm). Twenty-four extracted human molars were divided randomly in three groups. Six cavities were prepared on the coronal part of each tooth. Standard cavities (1.7 x 2 mm) were prepared. Cavities were acid etched, sealed with Scotch Bond 1 and filled by a hybrid composite. Cavities were exposed to one light source, thermocycled and immersed in a 2% methylene blue dye solution. Dye penetration in the leakage of cavities was recorded using a digital optical microscope. Mean values of percentage of dye penetrations in microleakages of cavities were 49.303 +/- 5.178% for cavities cured with LED, 44.486 +/- 6.075% with halogen bulb and 36.647 +/- 5.936% for those cured by argon laser. Statistically significant difference exists between cavities cured by halogen vs LED (P < 0.01), halogen vs laser (P < 0.001) and LED vs laser (P < 0.001). The lowest microleakage was observed in the cavities and composites cured with argon ion laser.


Subject(s)
Composite Resins/radiation effects , Curing Lights, Dental , Lasers, Gas , Humans , In Vitro Techniques
20.
Lasers Med Sci ; 24(1): 81-5, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18084810

ABSTRACT

The aim of this study was to determine whether it is safe to use photo-activated disinfection (PAD) during root canal treatment without heating the periodontal tissues. Root canals of 30 freshly extracted single-rooted teeth were prepared using ProFiles up to size ISO 40 and then filled with photo-sensitiser: tolonium blue (1.2 mg/l). The 635 nm diode laser was used with the manufacturer's endo-tip. Samples were irradiated for 150 s (output power 100 mW, approximate energy density 106.16 J/cm(2)). Temperatures were recorded at working length on the external root surface. After 150 s of PAD irradiation, the average temperature rise was 0.16 +/- 0.08 degrees C. All values were lower than the 7 degrees C safety level for periodontal injury. It was concluded that, regarding the temperature increase, the use of PAD in root canals could be considered harmless for periodontal tissues.


Subject(s)
Dental Pulp Cavity/radiation effects , Disinfection/methods , Lasers , Humans , In Vitro Techniques , Photosensitizing Agents/pharmacology , Temperature
SELECTION OF CITATIONS
SEARCH DETAIL
...