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1.
Philos Trans A Math Phys Eng Sci ; 382(2272): 20230218, 2024 Jun 09.
Article in English | MEDLINE | ID: mdl-38679054

ABSTRACT

The cutoff effect is a significant determinant of solar magnetohydrodynamic wave propagation and hence pivotal in energy transfer studies, such as solar plasma heating and seismological diagnostics. Despite continuous efforts, no good agreement between observed waveperiods and theory or numerical simulations was found. Our objective is to investigate the magnetoacoustic cutoff effect in the partially ionized solar atmosphere, factoring in the two-fluid effects. We developed a two-fluid MHD numerical model and used it to simulate a quiet region of the Sun from the top of the convective zone to the low corona. Our findings show that the ongoing granulation excites a wide range of waves propagating into the upper atmospheric layers. The cutoff waveperiods strongly depend on the height. Two-fluid waveperiods obtained with numerical simulations reproduce the recent observations at a very good level of compliance. Furthermore, direct comparison with strongly coupled cases that imitate the single-fluid approximation have shown that the waveperiod propagation pattern is only present in fully two-fluid simulations. We conclude that the presence of neutrals and therefore collisional terms change the dynamics of the magnetized plasma, in comparison with the single-fluid approximation. This effect is more prominently seen in the upper photosphere and chromosphere. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'.

2.
Mol Pharm ; 21(3): 1272-1284, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38361428

ABSTRACT

Rifampicin (RIF) is an antibiotic used to treat tuberculosis and leprosy. Even though RIF is a market-available drug, it has a low aqueous solubility, hindering its bioavailability. Among the strategies for bioavailability improvement of poorly soluble drugs, coamorphous systems have been revealed as an alternative in the increase of the aqueous solubility of drug systems and at the same time also increasing the amorphous state stability and dissolution rate when compared with the neat drug. In this work, a new coamorphous form from RIF and tromethamine (TRIS) was synthesized by slow evaporation. Structural, electronic, and thermodynamic properties and solvation effects, as well as drug-coformer intermolecular interactions, were studied through density functional theory (DFT) calculations. Powder X-ray diffraction (PXRD) data allowed us to verify the formation of a new coamorphous. In addition, the DFT study indicates a possible intermolecular interaction by hydrogen bonds between the available amino and carbonyl groups of RIF and the hydroxyl and amino groups of TRIS. The theoretical spectra obtained are in good agreement with the experimental data, suggesting the main interactions occurring in the formation of the coamorphous system. PXRD was used to study the physical stability of the coamorphous system under accelerated ICH conditions (40 °C and 75% RH), indicating that the material remained in an amorphous state up to 180 days. The thermogravimetry result of this material showed a good thermal stability up to 153 °C, and differential scanning calorimetry showed that the glass temperature (Tg) was at 70.0 °C. Solubility studies demonstrated an increase in the solubility of RIF by 5.5-fold when compared with its crystalline counterpart. Therefore, this new material presents critical parameters that can be considered in the development of new coamorphous formulations.


Subject(s)
Rifampin , Tromethamine , Drug Compounding , Solubility , Water , Models, Theoretical , Drug Stability , Calorimetry, Differential Scanning , X-Ray Diffraction
3.
J Environ Sci Health B ; 57(9): 697-709, 2022.
Article in English | MEDLINE | ID: mdl-35861013

ABSTRACT

Florpyrauxifen-benzyl is a systemic herbicide which acts on weeds of common occurrence in rice cultivation areas using flooded or rainfed systems. The Brazilian Health Regulatory Agency (ANVISA) authorized the commercialization of this pesticide, but did not establish guidelines with an extraction and quantification method of residues of this compound as a form of environmental monitoring. Therefore, the present study aimed to optimize and validate the liquid-liquid extraction with low temperature purification (LLE-LTP) to determine florpyrauxifen-benzyl content in water samples by high performance liquid chromatography with diode array detection (HPLC-DAD). The recovery ranged from 95.84 to 105.4% with a relative standard deviation less than 1.5. LLE-LTP was selective, precise, accurate, linear in the range from 4.00 to 150 µg L-1, and the limit of quantification was 4.00 µg L-1. The stability study of the compound in water revealed its degradation in 25 days and DT50 in approximately 5 days. LLE-LTP coupled to HPLC-DAD presented itself as a simple, easy and efficient method of extracting and analyzing it in water samples.


Subject(s)
Herbicides , Pesticides , Water Pollutants, Chemical , Chromatography, High Pressure Liquid/methods , Herbicides/chemistry , Pesticides/analysis , Water , Water Pollutants, Chemical/analysis
4.
Exp Gerontol ; 156: 111584, 2021 12.
Article in English | MEDLINE | ID: mdl-34653558

ABSTRACT

BACKGROUND: Oxidative stress is an important factor in the formation of atherosclerotic plaques. High-density lipoprotein (HDL) harbors paraoxonase-1 (PON-1) and glutathione peroxidase (GPx), key enzymes in the protection against the harmful effects of oxidative stress. Although exercise training can increase both HDL-c content and its antioxidant action, and glutamine (Gln) intake also promotes GPx-based defenses, the association between exercise training and Gln in the regulation of PON-1 activity was not explored. Therefore, the objective of this study was to investigate the effects of Gln supplementation on the redox balance and on the total HDL antioxidant capacity by evaluation of the activity of PON-1 and GPx enzymes in physically exercised elderly individuals compared to non-exercised ones. METHODS: Fifty-one practitioners of a combined exercise training program (CET, age: 71.9 ± 5.7 years) and 32 non-practitioners (NP, age: 73 ± 6.3 years) participated in the study. CET and NP groups were separated into 2 subgroups according to the supplementation: Gln, 0.3 g/kg/day + 10 g maltodextrin (CET-Gln, n = 26; and NP-Gln, n = 16) or placebo, 10 g maltodextrin (CET-PL, n = 25; and NP-PL, n = 16). Blood samples were drawn at baseline and after 30 days after commencement of the supplementation for biochemical and enzyme activity analyses. RESULTS: Increased HDL-c, total peroxidase (PRx), and GPx activities were found in both CET-Gln and NP-Gln after the supplementation period, compared to baseline, in opposition to CET-PL and NP-PL groups. PON-1 activity increased only in CET-Gln. In both CET-Gln and NP-Gln groups, there was a reduction of the total peroxides/PRx, iron/PRx, and total peroxides/GPX ratios after supplementation. In CET-Gln, thiobarbituric acid-reactive substances (TBARS)/PRx and TBARS/GPx ratios were also lower after supplementation. CET-Gln and CET-PL subgroups had lower glycemia than NP-Gln and NP-PL, either at baseline or after the supplementation periods. The other parameters were unchanged after supplementation [total cholesterol, LDL-c, triglycerides, non-HDL cholesterol, total peroxides, TBARS, iron serum, Trolox-equivalent antioxidant capacity (TEAC), and uric acid]. CONCLUSIONS: Gln supplementation can increase glutathione peroxidase activity regardless the individuals were physically active or sedentary, but the PON-1 activity only increased in physically active individuals. These results show the potential of Gln supplementation in the maintenance of the vascular redox balance, with potential implications for atherogenesis protection.


Subject(s)
Aryldialkylphosphatase , Glutamine , Aged , Antioxidants/pharmacology , Dietary Supplements , Glutathione Peroxidase , Humans , Lipoproteins, HDL/pharmacology , Oxidative Stress
5.
Parasitol Int ; 83: 102347, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33862253

ABSTRACT

Leishmania is an obligate intracellular parasite that primarily inhabits macrophages. The destruction of the parasite in the host cell is a fundamental mechanism for infection control. In addition, inhibition of the leishmanicidal activity of macrophages seems to be related to the ability of some species to inhibit the production of nitric oxide (NO) by depleting arginine. Some species of Leishmania have the ability to produce NO from a constitutive nitric oxide synthase-like enzyme (cNOS-like). However, the localization of cNOS-like in Leishmania has not been described before. As such, this study was designed to locate cNOS-like enzyme and NO production in promastigotes of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis. NO production was initially quantified by flow cytometry, which indicated a significant difference in NO production between L. (L.) amazonensis (GMFC = 92.17 +/- 4.6) and L. (V.) braziliensis (GMFC = 18.89 +/- 2.29) (P < 0.05). Analysis of cNOS expression by immunoblotting showed more expression in L. (L.) amazonensis versus L. (V.) braziliensis. Subsequently, cNOS-like immunolabeling was observed in promastigotes in regions near vesicles, the flagellar pocket and mitochondria, and small clusters of particles appeared to be fusing with vesicles suggestive of glycosomes, peroxisome-like-organelles that compartmentalize the glycolytic pathway in trypanosomatid parasites. In addition, confocal microscopy analysis demonstrated colocalization of cNOS-like and GAPDH, a specific marker for glycosomes. Thus, L. (L.) amazonensis produces greater amounts of NO than L. (V.) braziliensis, and both species present the cNOS-like enzyme inside glycosomes.


Subject(s)
Leishmania braziliensis/enzymology , Leishmania mexicana/enzymology , Nitric Oxide Synthase/metabolism , Nitric Oxide/biosynthesis , Protozoan Proteins/metabolism , Leishmaniasis, Cutaneous/metabolism , Leishmaniasis, Mucocutaneous/metabolism , Species Specificity
6.
Comput Methods Programs Biomed ; 173: 1-14, 2019 May.
Article in English | MEDLINE | ID: mdl-31046984

ABSTRACT

BACKGROUND AND OBJECTIVE: Leukaemia is a disease found worldwide; it is a type of cancer that originates in the bone marrow and is characterised by an abnormal proliferation of white blood cells (leukocytes). In order to correctly identify this abnormality, haematologists examine blood smears from patients. A diagnosis obtained by this method may be influenced by factors such as the experience and level of fatigue of the haematologist, resulting in non-standard reports and even errors. In the literature, several methods have been proposed that involve algorithms to diagnose this disease. However, no reviews or surveys have been conducted. This paper therefore presents an empirical investigation of computational methods focusing on the segmentation of leukocytes. METHODS: In our study, 15 segmentation methods were evaluated using five public image databases: ALL-IDB2, BloodSeg, Leukocytes, JTSC Database and CellaVision. Following the standard methodology for literature evaluation, we conducted a pixel-level segmentation evaluation by comparing the segmented image with its corresponding ground truth. In order to identify the strengths and weaknesses of these methods, we performed an evaluation using six evaluation metrics: accuracy, specificity, precision, recall, kappa, Dice, and true positive rate. RESULTS: The segmentation algorithms performed significantly differently for different image databases, and for each database, a different algorithm achieved the best results. Moreover, the two best methods achieved average accuracy values higher than 97%, with an excellent kappa index. Also, the average Dice index indicated that the similarity between the segmented leukocyte and its ground truth was higher than 0.85 for these two methods This result confirms the high level of similarity between these images but does not guarantee that a method has segmented all leukocyte nuclei. We also found that the method that performed best segmented only 58.44% of all leukocytes. CONCLUSIONS: Of the techniques used to segment leukocytes, we note that clustering algorithms, the Otsu threshold, simple arithmetic operations and region growing are the approaches most widely used for this purpose. However, these computational methods have not yet overcome all the challenges posed by this problem.


Subject(s)
Cell Nucleus/metabolism , Leukocytes/cytology , Algorithms , Cluster Analysis , Color , Cytological Techniques , Databases, Factual , Deep Learning , False Positive Reactions , Humans , Image Processing, Computer-Assisted/methods , Medical Informatics/methods , Models, Theoretical
7.
Int J Dent Hyg ; 16(2): e73-e78, 2018 May.
Article in English | MEDLINE | ID: mdl-28834178

ABSTRACT

OBJECTIVE: The objective of this study was to compare the efficacy of an essential oils mouth rinse and dental floss on dental plaque accumulation and gingivitis in interproximal areas. METHODS: With informed consent, a parallel randomized controlled clinical trial was developed with 60 third-year dental hygiene students, randomly divided into two non-blind groups of 30 individuals each. For a period of 2 weeks, one group used an essential oils mouth rinse, according to manufacturer's instructions, and the other group flossed twice a day. Both groups received a toothbrush and fluoridated toothpaste for home dental hygiene care. A baseline dental hygiene appointment consisted of tooth scaling, prophylaxis and collection of the study data, using the Lobene modified gingival index; Saxton & Ouderaa gingival bleeding index and the Quigley & Hein modified by Turesky dental plaque index. RESULTS: At baseline, there was no significant difference between the groups for interproximal gingival inflammation (P = .214), gingival bleeding (P = .829) and dental plaque accumulation (P = .860). After 2 weeks of treatment, no significant differences were found between the essential oils mouth rinse and dental flossing for reduction of interproximal gingival inflammation (P = .938) and bleeding (P = .307). Essential oils mouth rinse showed to be significantly better than dental flossing in reducing interproximal dental plaque accumulation (P = .006). CONCLUSION: The use of an essential oils mouth rinse may be advised, as a complement, for patients unable to floss effectively, as it is more effective in reducing interproximal dental plaque accumulation than dental floss.


Subject(s)
Dental Devices, Home Care/statistics & numerical data , Dental Plaque/prevention & control , Gingivitis/prevention & control , Mouthwashes/therapeutic use , Oils, Volatile/therapeutic use , Adult , Dental Plaque Index , Drug Combinations , Female , Humans , Male , Periodontal Index , Salicylates/therapeutic use , Terpenes/therapeutic use , Toothpastes/therapeutic use , Treatment Outcome
8.
Front Neuroanat ; 10: 23, 2016.
Article in English | MEDLINE | ID: mdl-27047345

ABSTRACT

It is known that microglial morphology and function are related, but few studies have explored the subtleties of microglial morphological changes in response to specific pathogens. In the present report we quantitated microglia morphological changes in a monkey model of dengue disease with virus CNS invasion. To mimic multiple infections that usually occur in endemic areas, where higher dengue infection incidence and abundant mosquito vectors carrying different serotypes coexist, subjects received once a week subcutaneous injections of DENV3 (genotype III)-infected culture supernatant followed 24 h later by an injection of anti-DENV2 antibody. Control animals received either weekly anti-DENV2 antibodies, or no injections. Brain sections were immunolabeled for DENV3 antigens and IBA-1. Random and systematic microglial samples were taken from the polymorphic layer of dentate gyrus for 3-D reconstructions, where we found intense immunostaining for TNFα and DENV3 virus antigens. We submitted all bi- or multimodal morphological parameters of microglia to hierarchical cluster analysis and found two major morphological phenotypes designated types I and II. Compared to type I (stage 1), type II microglia were more complex; displaying higher number of nodes, processes and trees and larger surface area and volumes (stage 2). Type II microglia were found only in infected monkeys, whereas type I microglia was found in both control and infected subjects. Hierarchical cluster analysis of morphological parameters of 3-D reconstructions of random and systematic selected samples in control and ADE dengue infected monkeys suggests that microglia morphological changes from stage 1 to stage 2 may not be continuous.

9.
PLoS One ; 10(10): e0139550, 2015.
Article in English | MEDLINE | ID: mdl-26465145

ABSTRACT

Milk whey proteins are well known for their high biological value and versatile functional properties, characteristics that allow its wide use in the food and pharmaceutical industries. In this work, a 24 kDa protein from buffalo cheese whey was analyzed by mass spectrometry and presented homology with Bos taurus beta-lactoglobulin. In addition, the proteins present in buffalo cheese whey were hydrolyzed with pepsin and with different combinations of trypsin, chymotrypsin and carboxypeptidase-A. When the TNBS method was used the obtained hydrolysates presented DH of 55 and 62% for H1 and H2, respectively. Otherwise for the OPA method the DH was 27 and 43% for H1 and H2, respectively. The total antioxidant activities of the H1 and H2 samples with and without previous enzymatic hydrolysis, determined by DPPH using diphenyl-p-picrylhydrazyl radical, was 4.9 and 12 mM of Trolox equivalents (TE) for H2 and H2Dint, respectively. The increased concentrations for H1 and H2 samples were approximately 99% and 75%, respectively. The in vitro gastrointestinal digestion efficiency for the samples that were first hydrolyzed was higher compared with samples not submitted to previous hydrolysis. After in vitro gastrointestinal digestion, several amino acids were released in higher concentrations, and most of which were essential amino acids. These results suggest that buffalo cheese whey is a better source of bioavailable amino acids than bovine cheese whey.


Subject(s)
Cheese/analysis , Food Analysis/methods , Protein Hydrolysates/chemistry , Whey Proteins/chemistry , Whey/metabolism , Amino Acids/chemistry , Animals , Antioxidants/chemistry , Biphenyl Compounds/chemistry , Buffaloes , Carboxypeptidases A/chemistry , Cattle , Chromans/chemistry , Chymotrypsin/chemistry , Gastrointestinal Tract/metabolism , Hydrolysis , Lactoglobulins/chemistry , Lactose/chemistry , Mass Spectrometry , Peptides/chemistry , Picrates/chemistry , Trypsin/chemistry
10.
Int J Mol Sci ; 14(2): 2875-902, 2013 Jan 30.
Article in English | MEDLINE | ID: mdl-23364611

ABSTRACT

Efficient, low-cost enzymatic hydrolysis of lignocellulosic residues is essential for cost-effective production of bioethanol. The production of ß-glucosidase, ß-xylosidase and xylanase by Colletotrichum graminicola was optimized using Response Surface Methodology (RSM). Maximal production occurred in wheat bran. Sugarcane trash, peanut hulls and corncob enhanced ß-glucosidase, ß-xylosidase and xylanase production, respectively. Maximal levels after optimization reached 159.3 ± 12.7 U g-1, 128.1 ± 6.4 U g-1 and 378.1 ± 23.3 U g-1, respectively, but the enzymes were produced simultaneously at good levels under culture conditions optimized for each one of them. Optima of pH and temperature were 5.0 and 65 °C for the three enzymes, which maintained full activity for 72 h at 50 °C and for 120 min at 60 °C (ß-glucosidase) or 65 °C (ß-xylosidase and xylanase). Mixed with Trichoderma reesei cellulases, C. graminicola crude extract hydrolyzed raw sugarcane trash with glucose yield of 33.1% after 48 h, demonstrating good potential to compose efficient cocktails for lignocellulosic materials hydrolysis.

11.
Int J Dent Hyg ; 6(3): 238-43, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18768029

ABSTRACT

UNLABELLED: Dental hygiene activities were developed as part of a randomized clinical trial designed to assess the safety of low-level mercury exposure from dental amalgam restorations. Along with dental-hygiene clinical work, a community programme was implemented after investigators noticed the poor oral hygiene habits of participants, and the need for urgent action to minimize oral health problems in the study population. OBJECTIVES: Clinical and community activity goal was to promote oral health and prevent new disease. Community activities involved participants and their fellow students and were aimed at providing education on oral health in a school environment. METHODS: Dental hygienists developed clinical work with prophylaxis, sealants application and topical fluoride and implemented the community programme with in-class sessions on oral health themes. Twice a month fluoride mouthrinses and bi-annual tooth brushing instructional activity took place. Participation at dental-hygiene activities, sealed teeth with no need of restoration and dental-plaque-index were measures used to evaluate success of the programme for the participants. RESULTS: Improvement in dental hygiene is shown by the decrease in dental plaque index scores (P < 0.0001); also sealants integrity is achieved in 86.3% of teeth. 888 (13.7%) teeth with sealants had to be restored or were lost. Children participated actively on dental hygiene activities. Teachers became aware of the problem and included oral-health in school curricula. CONCLUSION: Dental hygiene activities have shown to be helpful to promote dental hygiene, promote oral health and to provide school-age children with education on habits that will be important for their future good health.


Subject(s)
Health Education, Dental , Oral Hygiene , School Dentistry , Cariostatic Agents/therapeutic use , Child , Dental Care for Children , Dental Caries/prevention & control , Dental Devices, Home Care , Dental Plaque/prevention & control , Dental Plaque Index , Dental Prophylaxis , Feeding Behavior , Female , Fluorides, Topical/therapeutic use , Follow-Up Studies , Health Education, Dental/methods , Health Promotion , Health Services Accessibility , Humans , Male , Motivation , Mouthwashes/therapeutic use , Patient Education as Topic , Periodontal Diseases/prevention & control , Pit and Fissure Sealants/therapeutic use , Toothbrushing
12.
J Dent Res ; 87(5): 475-9, 2008 May.
Article in English | MEDLINE | ID: mdl-18434580

ABSTRACT

Mercury emitted from dental amalgam may select for increased numbers of antibiotic- or mercury-resistant commensal bacteria in patients and increase their risk for bacterial diseases that are resistant to common therapies. We hypothesized that the presence of dental amalgams would increase the level of mercury-, tetracycline-, ampicillin-, erythromycin-, or chloramphenicol-resistant oral and urinary bacteria as compared with levels in children receiving composite fillings. Samples were collected at baseline, 3-6 months after the initial dental treatment, and annually for 7 years of follow-up. There were no statistically significant differences between treatment groups in the numbers of bacteria growing on antibiotic- or mercury-supplemented plates. This study provided no evidence that amalgam fillings on posterior teeth influenced the level of antibiotic- or mercury-resistant oral or urinary bacteria as detected by culture.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Dental Amalgam/pharmacology , Dental Caries/microbiology , Drug Resistance, Microbial , Adolescent , Anti-Bacterial Agents/metabolism , Child , Dental Amalgam/metabolism , Dental Caries/therapy , Dental Restoration, Permanent/methods , Female , Humans , Longitudinal Studies , Male , Mouth/microbiology
13.
Int J Dent Hyg ; 6(1): 37-42, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18205652

ABSTRACT

OBJECTIVES: To obtain high school teachers evaluation of a Community Dental Hygiene programme, developed as part of a clinical trial designed to assess the safety of low-level mercury exposure from amalgam restorations. METHODS: A questionnaire to assess programme evaluation, personal opinion on programme relevance and satisfaction with activities was distributed among teachers. It had a total of 22 questions organized into three groups. RESULTS: A total of 25 questionnaires were obtained from teachers who participated in the programme. Ninety-two per cent of the respondents had a positive opinion concerning the existence of the programme. Eighty-eight per cent of the teachers believed that the programme changed student's knowledge about dental hygiene. Ninety-two per cent of teachers supported the existence of the programme and 88% of them disagreed with a statement that participation in the programme was a waste of time. Teachers who did not collaborate actively with dental hygiene activities indicated belief that the programme affected school activities (P = 0.003). Teachers who actively participated in the programme believe that dental hygiene activities were important for students (P = 0.005). CONCLUSIONS: Teacher evaluations of this kind of programme are critical for the development of school-based Dental Hygiene Education programmes. Teachers believe that Dental Hygiene Education is crucial for students' well-being.


Subject(s)
Health Education, Dental/methods , Oral Hygiene/education , Program Evaluation , School Dentistry , Teaching , Adult , Dental Prophylaxis , Female , Humans , Male , Middle Aged , Portugal , Surveys and Questionnaires
14.
Mem. Inst. Oswaldo Cruz ; 102(8): 953-958, Dec. 2007. mapas, graf
Article in English | LILACS | ID: lil-471862

ABSTRACT

Anopheles darlingi is the most important Brazilian malaria vector, with a widespread distribution in the Amazon forest. Effective strategies for vector control could be better developed through knowledge of its genetic structure and gene flow among populations, to assess the vector diversity and competence in transmitting Plasmodium. The aim of this study was to assess the genetic diversity of An. darlingi collected at four locations in Porto Velho, by sequencing a fragment of the ND4 mitochondrial gene. From 218 individual mosquitoes, we obtained 20 different haplotypes with a diversity index of 0.756, equivalent to that found in other neotropical anophelines. The analysis did not demonstrate significant population structure. However, haplotype diversity within some populations seems to be over-represented, suggesting the presence of sub-populations, but the presence of highly represented haplotypes complicates this analysis. There was no clear correlation among genetic and geographical distance and there were differences in relation to seasonality, which is important for malarial epidemiology.


Subject(s)
Animals , Anopheles/genetics , DNA, Mitochondrial/genetics , Genetic Variation , Insect Vectors/genetics , Anopheles/classification , Brazil , Haplotypes , Insect Vectors/classification , Population Density , Seasons
15.
Mem Inst Oswaldo Cruz ; 102(8): 953-8, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18209934

ABSTRACT

Anopheles darlingi is the most important Brazilian malaria vector, with a widespread distribution in the Amazon forest. Effective strategies for vector control could be better developed through knowledge of its genetic structure and gene flow among populations, to assess the vector diversity and competence in transmitting Plasmodium. The aim of this study was to assess the genetic diversity of An. darlingi collected at four locations in Porto Velho, by sequencing a fragment of the ND4 mitochondrial gene. From 218 individual mosquitoes, we obtained 20 different haplotypes with a diversity index of 0.756, equivalent to that found in other neotropical anophelines. The analysis did not demonstrate significant population structure. However, haplotype diversity within some populations seems to be over-represented, suggesting the presence of sub-populations, but the presence of highly represented haplotypes complicates this analysis. There was no clear correlation among genetic and geographical distance and there were differences in relation to seasonality, which is important for malarial epidemiology.


Subject(s)
Anopheles/genetics , DNA, Mitochondrial/genetics , Genetic Variation , Insect Vectors/genetics , Animals , Anopheles/classification , Brazil , Haplotypes , Insect Vectors/classification , Population Density , Seasons
16.
Mem Inst Oswaldo Cruz ; 98(6): 751-5, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14595450

ABSTRACT

Sand flies were collected in the central region of the state of Rondônia (W 64 degrees 30' to 63 degrees 00' and S 10 degrees 00'to 11 degrees 00') using Shannon and CDC light traps from October 1997 to August 2000. A total of 85,850 specimens representing 78 named species were captured. Of these 14 were new records for Rondônia. The proportion of males/females was 1/1.131. Trypanosomatids, that are presently being identified, were detected in 11 species. Leishmania (Viannia) naiffi was recorded from Psychodopygus davisi and P. hirsutus. In the present study the dominant species was P. davisi (39.6%) followed by Lutzomyia whitmani (13.1%), P. carrerai (11.6%), and P. hirsutus (10.2%). The importance of P. davisi as a vector of zoonotic cutaneous leishmaniasis is discussed.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Brazil , Female , Humans , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/parasitology , Male , Population Density , Psychodidae/parasitology , Seasons , Species Specificity
17.
Mem. Inst. Oswaldo Cruz ; 98(6): 751-755, Sept. 2003. tab
Article in English | LILACS | ID: lil-348342

ABSTRACT

Sand flies were collected in the central region of the state of Rondônia (W 64 30' to 63 00' and S 10 00'to 11 00') using Shannon and CDC light traps from October 1997 to August 2000. A total of 85,850 specimens representing 78 named species were captured. Of these 14 were new records for Rondônia. The proportion of males/females was 1/1.131. Trypanosomatids, that are presently being identified, were detected in 11 species. Leishmania (Viannia) naiffi was recorded from Psychodopygus davisi and P. hirsutus. In the present study the dominant species was P. davisi (39.6 percent) followed by Lutzomyia whitmani (13.1 percent), P. carrerai (11.6 percent), and P. hirsutus (10.2 percent). The importance of P. davisi as a vector of zoonotic cutaneous leishmaniasis is discussed


Subject(s)
Animals , Humans , Male , Female , Insect Vectors , Psychodidae , Brazil , Insect Vectors , Leishmaniasis, Cutaneous , Population Density , Psychodidae , Seasons
18.
Int J Dent Hyg ; 1(4): 223-6, 2003 Nov.
Article in English | MEDLINE | ID: mdl-16451504

ABSTRACT

The Dental Hygiene Program is a fairly recent addition in the field of the health professions in Portugal. In the past 19 years, the programme has developed community activities alongside with clinical work. This programme provides an education that is responsive, scientific and professional, in a learning environment that is dynamic, student-centred and that encourages collaboration between students and faculty. The community activities play a major role in the curricula of the programme and allow the students to develop skills in working with a wide range of population groups and to attend to their specific needs. Dental hygienists are integrated in health teams and work under the supervision of a physician or a dentist. Among other responsibilities, the following functions are part of the scope of the profession: to participate in health education programmes and sensitise the population to the prevention of dental diseases, to participate in the planning, implementation, and evaluation of the public health programmes and to perform clinical treatment for prevention and control of gingivitis, periodontitis, and dental caries. An overview of the activities developed in the year 2002 and future perspectives are presented in this article.


Subject(s)
Dental Hygienists , Clinical Competence , Community Dentistry , Curriculum , Dental Hygienists/education , Dental Prophylaxis , Health Education, Dental , Health Promotion , Humans , Patient Care Team , Portugal , Preventive Dentistry , Professional Practice , Public Health Dentistry
19.
Oral Microbiol Immunol ; 17(5): 304-10, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12354212

ABSTRACT

Little is known about carriage of Candida albicans, the predominant pathogenic yeast in oral infection, in children. We cultured buccal mucosal and gingival swabs from 150 Portuguese children to investigate the prevalence of C. albicans at baseline (before dental treatment), post-treatment, and 12, 24, and 36 months post-baseline. The children, aged 8 to 11 years at baseline, had no systemic disease or clinical symptoms of oral candidiasis. At each successive visit, respectively, 47, 32, 21, 27, and 28% of children were C. albicans positive, resulting in an almost 50% reduction in prevalence from baseline to post-treatment (P < 0.0005). Children who carried C. albicans at one visit had 3 to 20 times greater odds of carrying C. albicans at another visit. C. albicans was cultured from 12 children at all time-points and from 10 children at four time-points. Children with oral C. albicans frequently maintained carriage over time, even with regular dental care.


Subject(s)
Candida albicans/isolation & purification , Mouth/microbiology , Age Factors , Child , Colony Count, Microbial , Confidence Intervals , Dental Amalgam , Dental Care , Dental Caries/therapy , Dental Prophylaxis , Dental Restoration, Permanent , Female , Follow-Up Studies , Gingiva/microbiology , Humans , Logistic Models , Male , Mouth Mucosa/microbiology , Odds Ratio , Portugal , Sex Factors , Single-Blind Method
20.
Rev. AMRIGS ; 33(4): 322-6, out.-dez. 1989. tab
Article in Portuguese | LILACS | ID: lil-87802

ABSTRACT

O conhecimento que o indivíduo com diabetes mellitus tenha sobre a própria doença é importante tanto para seu manejo como para a adoçäo de medidas preventivas. Com o objetivo de avaliar conhecimentos básicos, foi realizado um estudo de base populacional, com 117 indivíduos com diabetes - 75 com diagnóstico prévio e 42 em que o diabetes foi detectado durante o estudo. Através da aplicaçäo de um questionário padronizado observou-se que o grau de conhecimento sobre diabetes nos dois grupos foi semelhante (56,2% de acertos no grupo com diagnóstico prévio e 47,4% no grupo detectado durante o estudo; p-0,38), havendo diferenças significativas apenas nas questöes sobre faixa glicêmica aceitável para controle, atitude frente a hipoglicemia e cuidados para prevençäo da gangrena. No entanto, o grau de conhecimento dos dois grupos é insatisfatório, sugerindo que os serviçÝs de saúde enfatizam pouco os aspectos educacionais no atendimento ao diabetes


Subject(s)
Humans , Male , Female , Diabetes Mellitus/epidemiology , Brazil , Cross-Sectional Studies , Health Education , Health Knowledge, Attitudes, Practice , Health Promotion , Patient Education as Topic
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