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1.
Community Dent Health ; 38(3): 178-181, 2021 Aug 31.
Article in English | MEDLINE | ID: mdl-33848406

ABSTRACT

INTRODUCTION: Developmental Defects of Enamel (DDEs) comprise qualitative and/or quantitative changes to the enamel during amelogenesis. The aetiology of DDE remains inconclusive. AIM: To determine the association of pre, peri, and postnatal factors with the presence of DDE. DESIGN: Cross-sectional study with 353 children (8 to 11 years-old) in a Brazilian town. METHODS: One calibrated dentist assessed DDE using the Developmental Defects of Enamel Index and a questionnaire collected medical and sociodemographic data. MAIN OUTCOMES: Children with at least one type of DDE were categorized into the DDE group. Subtypes of DDE were also recorded. RESULTS: 63.1% of children had at least one type of DDE. Diffuse opacity was present in 36.7%, demarcated opacity in 14.8%, and hypoplasia in 5.83% of the children. In multivariate analysis, demarcated opacities and hypoplasia were associated with birth weight ⟨ 2500g (OR = 4.82; 95% CI 1.23-1.95). CONCLUSION: Low birth weight predicted DDE.


Subject(s)
Dental Enamel Hypoplasia , Brazil/epidemiology , Child , Cross-Sectional Studies , Dental Enamel , Dental Enamel Hypoplasia/epidemiology , Humans , Prevalence , Risk Factors
2.
Eur J Pharm Biopharm ; 149: 192-217, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31982574

ABSTRACT

The central nervous system (CNS) is vulnerable to pathologic processes that lead to the development of neurodegenerative disorders like Alzheimer's, Parkinson's and Huntington's diseases, Multiple sclerosis or Amyotrophic lateral sclerosis. These are chronic and progressive pathologies characterized by the loss of neurons and the formation of misfolded proteins. Additionally, neurodegenerative diseases are accompanied by a structural and functional dysfunction of the blood-brain barrier (BBB). Although serving as a protection for the CNS, the existence of physiological barriers, especially the BBB, limits the access of several therapeutic agents to the brain, constituting a major hindrance in neurotherapeutics advancement. In this regard, nanotechnology-based approaches have arisen as a promising strategy to not only improve drug targeting to the brain, but also to increase bioavailability. Lipid nanocarriers such as liposomes, solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), microemulsions and nanoemulsions, have already proven their potential for enhancing brain transport, crossing more easily into the CNS and allowing the administration of medicines that could benefit the treatment of neurological pathologies. Given the socioeconomic impact of such conditions and the advent of nanotechnology that inevitably leads to more effective and superior therapeutics for their management, it is imperative to constantly update on the current knowledge of these topics. Herein, we provide insight on the BBB and the pathophysiology of the main neurodegenerative disorders. Moreover, this review seeks to highlight the several approaches that can be used to improve the delivery of therapeutic agents to the CNS, while also offering an extensive overview of the latest efforts regarding the use of lipid-based nanocarriers in the management of neurodegenerative diseases.


Subject(s)
Drug Delivery Systems , Nanoparticles , Neurodegenerative Diseases/drug therapy , Animals , Blood-Brain Barrier/metabolism , Brain/metabolism , Brain/physiopathology , Drug Carriers/chemistry , Humans , Lipids/chemistry , Nanotechnology , Neurodegenerative Diseases/physiopathology , Tissue Distribution
3.
Biomed Res Int ; 2017: 7207983, 2017.
Article in English | MEDLINE | ID: mdl-28845434

ABSTRACT

Breast cancer is the most frequent type of nonskin malignancy among women worldwide. In general, conventional cancer treatment options (i.e., surgery, radiotherapy, chemotherapy, biological therapy, and hormone therapy) are not completely effective. Recurrence and other pathologic situations are still an issue in breast cancer patients due to side effects, toxicity of drugs in normal cells, and aggressive behaviour of the tumours. From this point of view, breast cancer therapy and adjuvant methods represent a promising and challenging field for researchers. In the last few years, the use of some types of complementary medicines by women with a history of breast cancer has significantly increased such as phytotherapeutic products and nutritional supplements. Despite this, the use of such approaches in oncologic processes may be problematic and patient's health risks can arise such as interference with the efficacy of standard cancer treatment. The present review gives an overview of the most usual phytotherapeutic products and nutritional supplements with application in breast cancer patients as adjuvant approach. Regardless of the contradictory results of scientific evidence, we demonstrated the need to perform additional investigation, mainly well-designed clinical trials in order to establish correlations and allow for further validated outcomes concerning the efficacy, safety, and clinical evidence-based recommendation of these products.


Subject(s)
Breast Neoplasms/therapy , Dietary Supplements , Phytotherapy , Plant Extracts/therapeutic use , Chemotherapy, Adjuvant , Cimicifuga , Female , Humans , Panax , Tea , Vitamins/therapeutic use
4.
Arq. bras. med. vet. zootec ; 69(1): 225-233, jan.-fev. 2017. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-836704

ABSTRACT

Características produtivas e nutricionais de Brachiaria decumbens, submetida a condições de sombreamento (sol pleno, 20% e 70% de sombreamento), sem e com uso de fertilização (80 kg.ha-1 de N e K2O e 60 kg.ha-1 de P2O5), foram avaliadas no delineamento de blocos casualizados, com quatro repetições. As parcelas sombreadas foram alocadas em um sistema silvipastoril, enquanto aquelas a pleno sol foram avaliadas em um monocultivo de B. decumbens. O sombreamento severo promoveu reduções de 54% na massa seca verde, 59% na massa seca total e 58% na densidade volumétrica de forragem. Aumentos da massa de forragem e da densidade volumétrica em resposta ao fertilizante foram observados somente nas condições de sol pleno e sombreamento moderado. A adubação não influenciou nas características nutricionais da forragem, mas o sombreamento severo promoveu aumentos de 20 e 51% nos teores de clorofila e de proteína bruta, respectivamente. Reduções dos teores de fibra em detergente neutro e fibra em detergente ácido foram observadas com o sombreamento. Os teores de lignina e a digestibilidade in vitro da matéria seca não variaram com nenhum fator estudado (médias de 6,0 e 60,9%, respectivamente). A adubação de B. decumbens com dose moderada de NPK é recomendada para dosséis cultivados no sol pleno e sombreamento moderado, mas deve ser evitada em pastos severamente sombreados, pois não reflete aumento de massa de forragem nem melhorias de seu valor nutricional.(AU)


Productive and nutritional traits of Brachiaria decumbens, submitted to shading conditions (full sun, 20% and 70% shading) and fertilization levels (without or with 80 kg.ha-1 of N and K 2 O and 60 kg.ha-1 of P 2O5), were evaluated in a randomized complete block design, with four replications. The shading were allocated in a silvopastoral system, while full sun was obtained in an exclusive B. decumbens pasture. The severe shading reduced the green dry mass in 54%, total dry mass in 59% and the forage bulk density in 58%. Increases in the forage mass and forage bulk density in response to fertilization were observed only in full sun and moderate shade. The nutritional traits did not vary with fertilization, but the chlorophyll and crude protein contents increased 20 and 51% with severe shading, respectively. The neutral detergent fiber and acid detergent fiber reduced with shade. The lignin content and in vitro dry matter digestibility did not vary with factors (average values of 6.0 and 60.9%, respectively). Fertilization with moderate dose of NPK is recommended to B. decumbens in full sun and moderate shading, but should be avoided in severely shaded pasture, because not reflected in improvement of forage mass and its nutritional traits.(AU)


Subject(s)
Brachiaria/chemistry , Nutritive Value , Pasture/analysis , Plant Physiological Phenomena , Sunlight
5.
Plant Sci ; 251: 54-64, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27593463

ABSTRACT

Stomatal regulation of leaf gas exchange with the atmosphere is a key process in plant adaptation to the environment, particularly in semi-arid regions with high atmospheric evaporative demand. Development of stomata, integrating internal signaling and environmental cues sets the limit for maximum diffusive capacity of stomata, through size and density and is under a complex genetic control, thus providing multiple levels of regulation. Operational stomatal conductance to water vapor and CO2 results from feed-back and/or feed-forward mechanisms and is the end-result of a plethora of signals originated in leaves and/or in roots at each moment. CO2 assimilation versus water vapor loss, proposed to be the subject of optimal regulation, is species dependent and defines the water use efficiency (WUE). WUE has been a topic of intense research involving areas from genetics to physiology. In crop plants, especially in semi-arid regions, the question that arises is how the compromise of reducing transpiration to save water will impact on plant performance through leaf temperature. Indeed, plant transpiration by providing evaporative cooling, is a major component of the leaf energy balance. In this paper we discuss the dilemma of 'saving water or being cool' bringing about recent findings from molecular genetics, to development and physiology of stomata. The question of 'how relevant is screening for high/low WUE in crops for semi-arid regions, where drought and heat co-occur' is discussed.


Subject(s)
Crops, Agricultural/physiology , Plant Stomata/physiology , Plant Transpiration/genetics , Water/metabolism , Conservation of Natural Resources , Crop Production/methods
6.
Heredity (Edinb) ; 114(5): 525-36, 2015 May.
Article in English | MEDLINE | ID: mdl-25649502

ABSTRACT

Closely related sympatric species commonly develop different ecological strategies to avoid competition. Ctenomys minutus and C. flamarioni are subterranean rodents parapatrically distributed in the southern Brazilian coastal plain, showing a narrow sympatric zone. To gain understanding on food preferences and possible competition for food resources, we evaluated their diet composition performing DNA metabarcoding analyzes of 67 C. minutus and 100 C. flamarioni scat samples, collected along the species geographical ranges. Thirteen plant families, mainly represented by Poaceae, Araliaceae, Asteraceae and Fabaceae, were identified in the diet of C. minutus. For C. flamarioni, 10 families were recovered, with a predominance of Poaceae, Araliaceae and Asteraceae. A significant correlation between diet composition and geographical distance was detected in C. minutus, whereas the diet of C. flamarioni was quite homogeneous throughout its geographical distribution. No significant differences were observed between males and females of each species. However, differences in diet composition between species were evident according to multivariate analysis. Our results suggest some level of diet partitioning between C. flamarioni and C. minutus in the sympatric region. While the first species is more specialized on few plant items, the second showed a more varied and heterogeneous diet pattern among individuals. These differences might have been developed to avoid competition in the region of co-occurrence. Resource availability in the environment also seems to influence food choices. Our data indicate that C. minutus and C. flamarioni are generalist species, but that some preference for Poaceae, Asteraceae and Araliaceae families can be suggested for both rodents.


Subject(s)
DNA Barcoding, Taxonomic/methods , Diet/veterinary , Rodentia/physiology , Sympatry , Animals , Brazil , Ecosystem , Female , Geography , Male , Plants/genetics , Species Specificity
7.
Open Vet J ; 4(1): 59-64, 2014.
Article in English | MEDLINE | ID: mdl-26623340

ABSTRACT

Gestational diabetes mellitus (GDM) is defined as glucose intolerance first diagnosed during the second or third trimester of pregnancy. The treatment aims at glycemic control through changes in the patient's diet with or without exercise, but some patients need insulin therapy. An alternative would be to use oral hypoglycemic agents such as glibenclamide (GLIB). The present study aims to analyze the toxic effects of GLIB in fetuses of pregnant rats which received 5 or 20mg/kg doses of GLIB. Glycemic dosage reveals no significant difference between control (deionized water) and treated groups, showing that these concentrations of GLIB were not effective to cause hypoglycemia in rats. The vitality of the fetuses in all groups was 100%. GLIB administration promoted increase in weight and significant changes in measures of external morphological parameters of treated fetuses. Histological analysis revealed that liver lobes, lobules and central lobular veins were well defined for all treatments. However, GLIB animals presented a light brownish precipitate into the center-lobular veins and in the liver parenchyma among the hepatocytes. These results indicated a possible passage of the drug through the blood-placental membrane, without serious changes that impair the development of neither bone tissue, nor the liver of these animals.

8.
Colloids Surf B Biointerfaces ; 111: 755-63, 2013 Nov 01.
Article in English | MEDLINE | ID: mdl-23954816

ABSTRACT

Miconazole is a widely used antifungal agent with poor aqueous solubility, which requires the development of drug delivery systems able to improve its therapeutic activity. For this purpose, a miconazole-loaded nanostructured lipid carriers (NLC) dispersion was prepared and characterized. Further, the dispersion was used to prepare a NLC-based hydrogel formulation proposed as an alternative system to improve the local delivery of miconazole to the oral mucosa. NLC dispersion showed particles in the nanometer range (≈ 200 nm) with low polidispersity index (<0.3), good physical stability and high encapsulation efficiency (>87%). A controlled miconazole release was observed from NLC and NLC-based hydrogel formulations, in contrast to a commercial oral gel formulation, which demonstrated a faster release. Additionally, it was observed that the encapsulation of miconazole in the NLC improved its antifungal activity against Candida albicans. Therefore, it was demonstrated that the encapsulation of miconazole in NLC allows for obtaining the same therapeutic effect of a commercial oral gel formulation, using a 17-fold lower dose of miconazole.


Subject(s)
Antifungal Agents/pharmacology , Drug Carriers/chemistry , Drug Delivery Systems , Lipids/chemistry , Miconazole/pharmacology , Mouth Mucosa/drug effects , Nanostructures/chemistry , Calorimetry, Differential Scanning , Candida albicans/drug effects , Chemistry, Pharmaceutical , Crystallization , Hydrogels/pharmacology , Kinetics , Particle Size , Placebos , Rheology/drug effects , Static Electricity
9.
Heredity (Edinb) ; 111(4): 293-305, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23759727

ABSTRACT

Identifying factors and the extent of their roles in the differentiation of populations is of great importance for understanding the evolutionary process in which a species is involved. Ctenomys minutus is a highly karyotype-polymorphic subterranean rodent, with diploid numbers ranging from 42 to 50 and autosomal arm numbers (ANs) ranging from 68 to 80, comprising a total of 45 karyotypes described so far. This species inhabits the southern Brazilian coastal plain, which has a complex geological history, with several potential geographical barriers acting on different time scales. We assessed the geographical genetic structure of C. minutus, examining 340 individuals over the entire distributional range and using information from chromosomal rearrangements, mitochondrial DNA (mtDNA) sequences and 14 microsatellite loci. The mtDNA results revealed seven main haplogroups, with the most recent common ancestors dating from the Pleistocene, whereas clustering methods defined 12 populations. Some boundaries of mtDNA haplogroups and population clusters can be associated with potential geographical barriers to gene flow. The isolation-by-distance pattern also has an important role in fine-scale genetic differentiation, which is strengthened by the narrowness of the coastal plain and by common features of subterranean rodents (that is, small fragmented populations and low dispersal rates), which limit gene flow among populations. A step-by-step mechanism of chromosomal evolution can be suggested for this species, mainly associated with the metapopulation structure, genetic drift and the geographical features of the southern Brazilian coastal plain. However, chromosomal variations have no or very little role in the diversification of C. minutus populations.


Subject(s)
Chromosome Aberrations , DNA, Mitochondrial/genetics , Microsatellite Repeats/genetics , Rodentia/genetics , Animals , Biological Evolution , Brazil , Genetic Variation , Haplotypes , Humans , Karyotyping , Molecular Sequence Data , Sequence Analysis, DNA , United States
10.
Curr Med Chem ; 19(26): 4495-510, 2012.
Article in English | MEDLINE | ID: mdl-22834821

ABSTRACT

The hydrophobic character of most drug molecules and their potential for degradation under the hostile environment of the gastrointestinal tract (GIT) constitutes the main obstacle in the development of a successful oral drug delivery system, since these are related to limitations of bioavailability and absorption processes. However, according to the advantages of the oral route, alternative ways of drug administration in the oral cavity should be considered. In this context, it is essential to have a systematic knowledge of the GIT and the oral cavity components, for a better understanding of the processes taking place during the oral administration of drugs. This review gives an overview of those anatomical and physiological features and elucidates about the current approaches employed to enhance the bioavailability of oral poorly water-soluble drugs. Strategies including the uses of lipid-based nanocarriers, such as nanoemulsions, liposomes and lipid nanoparticles are discussed, considering their ability to improve solubility, dissolution kinetics, absorption and, consequently, biopharmaceutical properties. Some toxicological concerns are also highlighted.


Subject(s)
Drug Carriers/administration & dosage , Drug Carriers/chemistry , Drug Delivery Systems/methods , Lipids/chemistry , Mouth Mucosa/drug effects , Mouth Mucosa/metabolism , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/chemistry , Administration, Oral , Biological Availability , Humans , Lipids/administration & dosage , Solubility , Water/chemistry
11.
Eur J Pharm Sci ; 45(5): 606-12, 2012 Apr 11.
Article in English | MEDLINE | ID: mdl-22245537

ABSTRACT

Surface hydrophobicity of nanocarriers influences protein binding and subsequently fate of nanoparticles in blood circulation. Therefore, characterization of surface hydrophobicity of nanocarriers provides important preclinical information. Here, a modified classical adsorption method for the needs of characterization of cationic solid lipid nanoparticles (cSLN) was developed. We have identified possible method limitations that should be considered when performing the analysis, i.e. the problems associated with particle separation from the dispersion and their own absorbance in visible spectrum. We propose two modified methods for performing the assay overcoming the stated limitations. We also discuss here evaluation by different approaches (calculation of binding constants or partitioning quotient) and their suitability for the prepared cSLN formulation. Overall, we confirmed that our modified adsorption method can provide useful information about surface properties of (cationic) SLN, however, performing and evaluation of the assay need special attention in order to obtain the desired results.


Subject(s)
Lipids/chemistry , Nanoparticles/chemistry , Rose Bengal/chemistry , Adsorption , Cations/chemistry , Drug Carriers/chemistry , Hydrophobic and Hydrophilic Interactions , Particle Size , Surface Properties
12.
Int J Pharm ; 420(2): 341-9, 2011 Nov 28.
Article in English | MEDLINE | ID: mdl-21907778

ABSTRACT

Cationic solid lipid nanoparticles (cSLN) are promising lipid nanocarriers for intracellular gene delivery based on well-known and widely accepted materials. cSLN containing single-chained cationic lipid cetyltrimethylammonium bromide were produced by high pressure homogenization and characterized in terms of (a) particle size distribution by photon correlation spectroscopy (PCS) and laser diffractometry (LD), (b) thermal behaviour using differential scanning calorimetry (DSC) and (c) the presence of various polymorphic phases was confirmed by X-ray diffraction (WAXD). SLN composed of Imwitor 900P (IMW) showed different pDNA stability and binding capacity in comparison to those of Compritol 888 ATO (COM). IMW-SLN, having z-ave=138-157 nm and d(0.5)=0.15-0.158 µm could maintain this size for 14 days at room temperature. COM-SLN had z-ave=334 nm and d(0.5)=0.42 µm on the day of production and could maintain similar size during 90 days. IMW-SLN revealed improved pDNA binding capacity. We attempted to explain these differences by different interactions between the solid lipid and the tested cationic lipid.


Subject(s)
DNA/chemistry , Glycerides/chemistry , Nanoparticles/chemistry , Calorimetry, Differential Scanning , Cations/chemistry , Cetrimonium , Cetrimonium Compounds/chemistry , Drug Carriers , Drug Stability , Particle Size , Poloxamer/chemistry , Surface-Active Agents/chemistry , X-Ray Diffraction
13.
Climacteric ; 14(1): 140-5, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20497031

ABSTRACT

OBJECTIVES: To evaluate the effects of acupuncture and sham-acupuncture on women with menopausal symptoms as reflected in the intensity of their hot flushes and the Kupperman Menopausal Index (KMI). METHOD: This was a randomized, single-blind, placebo-controlled, cross-over trial with 81 patients assigned to two groups: Group 1 received 12 months of acupuncture, then 6 months of sham-acupuncture treatment (n = 56) and Group 2 received 6 months of sham-acupuncture, then 12 months of acupuncture treatment (n = 25). The needles were inserted in a harmonic craniocaudal manner at a depth of about 2 cm, and each session lasted approximately 40 min. The efficacy of acupuncture in ameliorating the climacteric symptoms of patients in postmenopause was determined through the KMI and the intensity of hot flushes. The analysis of variance method for two factors and repeated measures was applied. RESULTS: The baseline values of the women in both groups were similar for the KMI score and number of hot flushes. At the end of 6 months, the values for the KMI and hot flushes for the women in Group 1 were lower than those of the women in Group 2 (p < 0.05). After 12 months, the KMI and hot flush data were similar in both groups. After 18 months, the values of the KMI and hot flushes for the women in Group 2 for were lower than those of the women in Group 1 (p < 0.05). CONCLUSION: Acupuncture treatment for relieving menopausal symptoms may be effective for decreasing hot flushes and the KMI score in postmenopausal women.


Subject(s)
Acupuncture Therapy , Hot Flashes/therapy , Climacteric , Cross-Over Studies , Female , Humans , Middle Aged , Prospective Studies , Single-Blind Method
14.
Pharmazie ; 65(2): 75-82, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20225647

ABSTRACT

The introduction of nanoparticulate carriers (NPC) in the pharmaceutic and nutraceutic fields has changed the definitions of disease management and treatment, diagnosis, as well as the supply food chain in the agri-food sector. NPC composed of synthetic polymers, proteins or polysaccharides gather interesting properties to be used for oral administration of pharmaceutics and nutraceutics. Oral administration remains the most convenient way of delivering drugs (e.g. peptides, proteins and nucleic acids) since these suffer similar metabolic pathways as food supply. Recent advances in biotechnology have produced highly potent new molecules however with low oral bioavailability. A suitable and promising approach to overcome their sensitivity to chemical and enzymatic hydrolysis as well as the poor cellular uptake, would be their entrapment within suitable gastrointestinal (GI) resistant NPC. Increasing attention has been paid to the potential use of NPC for peptides, proteins, antioxidants (carotenoids, omega fatty acids, coenzyme Q10), vitamins, probiotics, for oral administration. This review focuses on the most important materials to produce NPC for oral administration, and the most recent achievements in the production techniques and bioactives successfully delivered by these means.


Subject(s)
Dietary Supplements/analysis , Drug Carriers , Nanoparticles , Pharmaceutical Preparations/administration & dosage , Administration, Oral , Albumins/chemistry , Animals , Chemistry, Pharmaceutical , Excipients , Gelatin/chemistry , Humans , Polymers , Polysaccharides/chemistry
15.
Ann Bot ; 105(5): 661-76, 2010 May.
Article in English | MEDLINE | ID: mdl-20299345

ABSTRACT

BACKGROUND: A large proportion of vineyards are located in regions with seasonal drought (e.g. Mediterranean-type climates) where soil and atmospheric water deficits, together with high temperatures, exert large constraints on yield and quality. The increasing demand for vineyard irrigation requires an improvement in the efficiency of water use. Deficit irrigation has emerged as a potential strategy to allow crops to withstand mild water stress with little or no decreases of yield, and potentially a positive impact on fruit quality. Understanding the physiological and molecular bases of grapevine responses to mild to moderate water deficits is fundamental to optimize deficit irrigation management and identify the most suitable varieties to those conditions. SCOPE: How the whole plant acclimatizes to water scarcity and how short- and long-distance chemical and hydraulic signals intervene are reviewed. Chemical compounds synthesized in drying roots are shown to act as long-distance signals inducing leaf stomatal closure and/or restricting leaf growth. This explains why some plants endure soil drying without significant changes in shoot water status. The control of plant water potential by stomatal aperture via feed-forward mechanisms is associated with 'isohydric' behaviour in contrast to 'anysohydric' behaviour in which lower plant water potentials are attained. This review discusses differences in this respect between grapevines varieties and experimental conditions. Mild water deficits also exert direct and/or indirect (via the light environment around grape clusters) effects on berry development and composition; a higher content of skin-based constituents (e.g. tannins and anthocyanins) has generally being reported. Regulation under water deficit of genes and proteins of the various metabolic pathways responsible for berry composition and therefore wine quality are reviewed.


Subject(s)
Adaptation, Physiological/physiology , Plant Transpiration/physiology , Vitis/metabolism , Water/metabolism , Abscisic Acid/metabolism
16.
Braz. j. biol ; 67(4,supl): 839-847, Dec. 2007. mapas
Article in English | LILACS | ID: lil-474222

ABSTRACT

The goal of conservation biology should be related to the preservation of species and also to the evolutionary and ecological processes that were responsible to form them and that are still acting. We review the conservation status of the species of tuco-tuco (Ctenomys torquatus, C. lami, C. minutus, and C. flamarioni) from southern Brazil, and relate these data to the geological history of a particular area in that region, the Coastal Plain of the States of Rio Grande do Sul and Santa Catarina. The implications of the data on these species from the Southeastern Brazil are also discussed in relation to the evolution and risk of extinction of these subterranean rodents.


O objetivo da biologia da conservação deve estar relacionado com a preservação das espécies e também com os processos evolutivos e ecológicos que foram responsáveis por sua formação e que continuam ocorrendo. Este trabalho revisa o status de conservação das espécies de tuco-tuco (Ctenomys torquatus, C. lami, C. minutus e C. flamarioni) do sul do Brasil, assim como a relação entre estas informações e a história geológica de uma região de especial importância, a planície costeira dos Estados do Rio Grande do Sul e Santa Catarina. São também discutidas as implicações do conhecimento acumulado sobre as espécies de tuco-tuco no sul do Brasil em relação aos aspectos evolutivos e a ameaça de extinção que estas espécies de roedores subterrâneos sofrem.


Subject(s)
Animals , Conservation of Natural Resources , Chromosomes/genetics , Genetic Variation , Rodentia/genetics , Brazil , Geography , Karyotyping
17.
Infect Genet Evol ; 7(4): 469-75, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17336167

ABSTRACT

The maculata group currently comprises two species of Triatominae, Triatoma maculata and Triatoma pseudomaculata, which share morphologic and chromatic characteristics. In order to clarify the systematic status of these two vectors of Trypanosoma cruzi and to infer their evolutionary relationships, we performed an enzymatic, morphometric and cytogenetic comparison of them, also taking into account two sister species not included in the group (T. arthurneivai and T. wygodzinskyi). According to our results, T. maculata and T. pseudomaculata belong to distinct evolutionary lineages. Similarly, T. arthurneivai topotypes from Minas Gerais form an independent isolated group by morphometrics. Our results also support the specific status of the Triatoma population from São Paulo State (formerly referred to T. arthurneivai), and suggest the possibility that it is T. wygodzinskyi. Finally, we suggest that only the arboricolous T. pseudomaculata from northeast Brazil and the rupicolous sister species originated from São Paulo State should be classified together in the same group.


Subject(s)
Evolution, Molecular , Triatoma/classification , Triatoma/genetics , Animals , Biometry , Chromosome Banding , Electrophoresis , Isoenzymes , Phenotype , Species Specificity , Triatoma/anatomy & histology , Triatoma/enzymology
18.
Braz J Biol ; 67(4 Suppl): 839-47, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18278350

ABSTRACT

The goal of conservation biology should be related to the preservation of species and also to the evolutionary and ecological processes that were responsible to form them and that are still acting. We review the conservation status of the species of tuco-tuco (Ctenomys torquatus, C. lami, C. minutus, and C. flamarioni) from southern Brazil, and relate these data to the geological history of a particular area in that region, the Coastal Plain of the States of Rio Grande do Sul and Santa Catarina. The implications of the data on these species from the Southeastern Brazil are also discussed in relation to the evolution and risk of extinction of these subterranean rodents.


Subject(s)
Chromosomes/genetics , Conservation of Natural Resources , Genetic Variation/genetics , Rodentia/genetics , Animals , Brazil , Geography , Karyotyping
19.
Vet Parasitol ; 130(3-4): 343-6, 2005 Jun 30.
Article in English | MEDLINE | ID: mdl-15908125

ABSTRACT

Populational flux of the adult phase of Stomoxys calcitrans was observed in the municipal district of Pedro Leopoldo, Minas Gerais, Brazil. Three biocenoses were selected for the study: stable agrobiocenosis, pastural agrobiocenosis and eubiocenosis. The occurrence and the populational flux of the insects, using the Magoon trap for their capture, were established. For each trap located in different biocenoses, a crossbred calf (Bos taurusxBos indicus) approximately 6-month-old was used as "live bait," exposed weekly for 48h in the traps. Of the three agrobiocenoses studied, the stable agrobiocenosis contributed the greatest number of specimens of. S. calcitrans captured, corresponding to 96.9% of the total flies of this species collected. S. calcitrans shows seasonal behavior for approximately 6 months (spring and summer being the rainiest months of the year). The population peaked during the months of November and December. During the months of July and August, there was no capture of flies.


Subject(s)
Ecosystem , Muscidae/physiology , Animals , Brazil , Population Dynamics , Seasons
20.
Braz. j. med. biol. res ; 37(5): 683-689, May 2004. tab
Article in English | LILACS | ID: lil-357540

ABSTRACT

Few data are available in the literature concerning the efficacy of standard hysteroscope disinfection procedures to prevent hepatitis B transmission. The aim of the present study was to determine the risk of hepatitis B virus (HBV) transmission during hysteroscopy among anti-HBc-seropositive women. Serum and hysteroscopic samples were collected from 62 women after diagnostic hysteroscopy. All samples were tested for serologic HBV markers. Polymerase chain reactions (PCR) were carried out to amplify regions C and S of the viral genome and only samples amplified by both pairs of primers were considered to be positive. Anti-HBc was repeatedly reactive in 48 (77 percent) of 62 serum samples, and HBsAg was detected in 8 (13 percent). At least one HBV serologic marker was found in 49 (79 percent) samples. Only one sample was HBsAg positive and anti-HBc negative. HBV-DNA was detected by PCR in 7 serum samples but in only 3 hysteroscopic samples obtained just after hysteroscopy. It is noteworthy that high levels of anti-HBc IgM were detected in one HBsAg-negative patient who showed an HBV-DNA-positive hysteroscopic sample. An elevated sample/cut-off ratio for anti-HBc IgM suggests recent infection and reinforces the need for testing for HBsAg and anti-HBc before hysteroscopy, since acute hepatitis B can be clinically asymptomatic. Viral DNA was not detected in any hysteroscopic samples collected after washing and disinfecting procedures with glutaraldehyde. We conclude that HBV-DNA can be found in the hysteroscope soon after hysteroscopy, but standard disinfecting procedures are effective in viral removal.


Subject(s)
Humans , Female , Disinfection , Hepatitis B , Hepatitis B Antibodies , Hepatitis B virus , Hysteroscopy , Biomarkers , DNA, Viral , Risk Factors
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