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1.
Artigo em Inglês | MEDLINE | ID: mdl-38820010

RESUMO

BACKGROUND: Multifidus is an important lumbar muscle with distinct superficial and deep fibers responsible for torque production and stabilization, respectively. Its mechanical properties change when transitioning from lying to sitting positions, necessitating enhanced stability. It holds crucial clinical relevance to assess these layers separately, especially in the sitting posture, which demands increased neuromuscular control compared to the prone position. OBJECTIVE: To compare lumbar multifidus stiffness in lying versus sitting postures, analyzing both superficial and deep layers. METHODS: Supersonic Shear Imaging captured elastographic images from 26 asymptomatic volunteers in prone and seated positions. RESULTS: Left multifidus shear modulus in lying: 5.98 ± 1.80/7.96 ± 1.59 kPa (deep/superficial) and sitting: 12.58 ± 4.22/16.04 ± 6.65 kPa. Right side lying: 6.08 ± 1.97/7.80 ± 1.76 kPa and sitting: 13.25 ± 4.61/17.95 ± 7.12 kPa. No side differences (lying p= 0.99, sitting p= 0.43). However, significant inter-postural differences occurred. CONCLUSION: Lumbar multifidus exhibits increased stiffness in sitting, both layers affected, with superior stiffness in superficial versus deep fibers. Applying these findings could enhance assessing multifidus stiffness changes, for classifying tension-induced low back pain stages.

2.
Biosensors (Basel) ; 14(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534235

RESUMO

This work presents a low-cost transcription loop-mediated isothermal amplification (RT-LAMP) instrument for nucleic acid detection, employing an Arduino Nano microcontroller. The cooling system includes customized printed circuit boards (PCBs) that serve as electrical resistors and incorporate fans. An aluminum block is designed to accommodate eight vials. The system also includes two PCB heaters-one for sample heating and the other for vial lid heating to prevent condensation. The color detection system comprises a TCS3200 color 8-sensor array coupled to one side of the aluminum heater body and a white 8-LED array coupled to the other side, controlled by two Multiplexer/Demultiplexer devices. LED light passes through the sample, reaching the color sensor and conveying color information crucial for detection. The top board is maintained at 110 ± 2 °C, while the bottom board is held at 65 ± 0.5 °C throughout the RT-LAMP assay. Validation tests successfully demonstrated the efficacy of the colorimetric RT-LAMP reactions using SARS-CoV-2 RNA amplification as a sample viability test, achieving 100% sensitivity and 97.3% specificity with 66 clinical samples. Our instrument offers a cost-effective (USD 100) solution with automated result interpretation and superior sensitivity compared to visual inspection. While the prototype was tested with SARS-CoV-2 RNA samples, its versatility extends to detecting other pathogens using alternative primers, showcasing its potential for broader applications in biosensing.


Assuntos
RNA Viral , DNA Polimerase Dirigida por RNA , DNA Polimerase Dirigida por RNA/genética , RNA Viral/genética , Alumínio , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , RNA Polimerases Dirigidas por DNA , Sensibilidade e Especificidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-36232006

RESUMO

Objective-The aim was to verify the correlation between cerebral and muscular electrical activity in subjects trained in virtual reality after a stroke. Method-The trial design was a cross-sectional study. Fourteen volunteers who were diagnosed with a stroke participated in the study. The intervention protocol was to perform functional activity with an upper limb using virtual reality. The functional protocol consisted of four one-minute series with a two-minute interval between series in a single session. Results-We observed, at initial rest, a positive correlation between brachii biceps and the frontal canal medial region (F7/F8) (r = 0.59; p = 0.03) and frontal canal lateral region (F3/F4) (r = 0.71; p = 0.006). During the activity, we observed a positive correlation between the anterior deltoid and frontal anterior channel (AF3/AF4) (r = 0.73; p = 0.004). At final rest, we observed a positive correlation between the anterior deltoid and temporal region channel (T7/T8) (r = 0.70; p = 0.005). Conclusions-We conclude that there was no correlation between brain and muscle activity for the biceps brachii muscle in subjects trained with virtual reality. However, there was a positive correlation for the deltoid anterior muscle.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Terapia de Exposição à Realidade Virtual , Realidade Virtual , Encéfalo , Estudos Transversais , Humanos , Músculos , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Extremidade Superior
4.
J Surg Oncol ; 126(1): 20-27, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35689578

RESUMO

BACKGROUND: Risk-reducing operations are an important part of the management of hereditary predisposition to cancer. In selected cases, they can considerably reduce the morbidity and mortality associated with cancer in this population. OBJECTIVES: The Brazilian Society of Surgical Oncology (BSSO) developed this guideline to establish national benchmarks for cancer risk-reducing operations. METHODS: The guideline was prepared from May to December 2021 by a multidisciplinary team of experts to discuss the surgical management of cancer predisposition syndromes. Eleven questions were defined and assigned to expert groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including risk-reducing colectomy, gastrectomy, and thyroidectomy, a major agreement was achieved by the participants, always using accessible alternatives. CONCLUSION: This and its accompanying article represent the first guideline in cancer risk reduction surgery developed by the BSSO and it should serve as an important reference for the management of families with cancer predisposition.


Assuntos
Neoplasias , Oncologia Cirúrgica , Brasil/epidemiologia , Humanos , Glândula Tireoide
5.
Microchem J ; 180: 107600, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35620142

RESUMO

This work describes the development of a Point-of-Care (POC) Lab-on-a-Chip (LOC) instrument for diagnosis of SARS-CoV-2 by Reverse-Transcription Loop-mediated isothermal amplification (RT-LAMP). The hardware is based on a Raspberry Pi computer ($35), a video camera, an Arduino Nano microcontroller, a printed circuit board as a heater and a 3D printed housing. The chips were manufactured in polymethyl methacrylate (PMMA) using a CO2 laser cutting machine and sealed with a PCR optic plastic film. The chip temperature is precisely controlled by a proportional-integral-derivative (PID) algorithm. During the RT-LAMP amplifications the chip was maintained at ∼ (65.0 ± 0.1) °C for 25 minutes and 5 minutes cooling down, totaling a 30 minutes of reaction .The software interpretation occurs in less than a second. The chip design has four 25 µL chambers, two for clinical samples and two for positive and negative control-samples. The RT-LAMP master mix solution added in the chip chambers contains the pH indicator Phenol Red, that is pink (for pH ∼ 8.0) before amplification and becomes yellow (pH ∼ 6.0) if the genetic material is amplified. The RT-LAMP SARS-CoV-2 diagnostic was made by color image recognition using the OpenCV machine vision software library. The software was programmed to automatically distinguish the HSV color parameter distribution in each one of the four chip chambers. The instrument was successfully tested for SARS-CoV-2 diagnosis, in 22 clinic samples, 11 positives and 11 negatives, achieving an assertiveness of 86% when compared to the results obtained by RT-LAMP standard reactions performed in conventional PCR equipment.

6.
Front Microbiol ; 12: 710359, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566915

RESUMO

Zika virus (ZIKV) is an arthropod-born virus that is mainly transmitted to humans by mosquitoes of the genus Aedes spp. Since its first isolation in 1947, only a few human cases had been described until large outbreaks occurred on Yap Island (2007), French Polynesia (2013), and Brazil (2015). Most ZIKV-infected individuals are asymptomatic or present with a self-limiting disease and nonspecific symptoms such as fever, myalgia, and headache. However, in French Polynesia and Brazil, ZIKV outbreaks led to the diagnosis of congenital malformations and microcephaly in newborns and Guillain-Barré syndrome (GBS) in adults. These new clinical presentations raised concern from public health authorities and highlighted the need for anti-Zika treatments and vaccines to control the neurological damage caused by the virus. Despite many efforts in the search for an effective treatment, neither vaccines nor antiviral drugs have become available to control ZIKV infection and/or replication. Flavonoids, a class of natural compounds that are well-known for possessing several biological properties, have shown activity against different viruses. Additionally, the use of flavonoids in some countries as food supplements indicates that these molecules are nontoxic to humans. Thus, here, we summarize knowledge on the use of flavonoids as a source of anti-ZIKV molecules and discuss the gaps and challenges in this area before these compounds can be considered for further preclinical and clinical trials.

7.
Front Endocrinol (Lausanne) ; 12: 627167, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815286

RESUMO

The increased incidence of thyroid diseases raises a series of questions about what the main predisposing factors are nowadays. If dietary restriction of iodine was once a major global health concern, today, the processes of industrialization of food and high exposure to a wide variety of environmental chemicals may be affecting, directly or indirectly, thyroid function. The homeostasis of hypothalamus-pituitary-thyroid (HPT) axis is finely regulated through the negative feedback mechanism exerted by thyroid hormones. Allostatic mechanisms are triggered to adjust the physiology of HPT axis in chronic conditions. Glyphosate and glyphosate-based herbicides are pesticides with controversial endocrine disrupting activities and only few studies have approached their effects on HPT axis and thyroid function. However, glyphosate has an electrophilic and nucleophilic zwitterion chemical structure that may affect the mechanisms involved in iodide oxidation and organification, as well as the oxidative phosphorylation in the ATP synthesis. Thus, in this review, we aimed to: (1) discuss the critical points in the regulation of HPT axis and thyroid hormones levels balance, which may be susceptible to the toxic action of glyphosate and glyphosate-based herbicides, correlating the molecular mechanisms involved in glyphosate toxicity described in the literature that may, directly or indirectly, be associated to the higher incidence of thyroid diseases; and (2) present the literature regarding glyphosate toxicity in HPT axis.


Assuntos
Exposição Ambiental , Glicina/análogos & derivados , Herbicidas/toxicidade , Doenças da Glândula Tireoide/induzido quimicamente , Doenças da Glândula Tireoide/epidemiologia , Glicina/toxicidade , Humanos , Incidência , Prevalência , Glifosato
8.
Biomed Microdevices ; 23(2): 24, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33855638

RESUMO

This article describes the fabrication of a low-cost Polymerase Chain Reaction (PCR) instrument to detect diseases. In order to reduce the instrument price and simplify construction we developed an alternative fabrication process, transforming conventional printed circuit boards (PCB) in heating elements, avoiding the use of aluminum heating/cooling blocks and Peltier devices. To cool down the reaction a simple computer fan was used. The vial holder was fabricated using two double side PCB boards assembled in a sandwich-like configuration. The bottom PCB has a resistance of 0.9 Ω used to heat the reaction mix, while the top layer has a resistance of 1.1 Ω to heat the vial body, preventing vapor condensation. The top board was maintained at ~ 110 ± 1 °C during all cycles. The final device was able to heat and cool down the reaction at rates of ~ 2.0 °C/s, a rate comparable to commercial thermocyclers. An SMD NTC thermistor was used as temperature sensors, and a PID (proportional-integral-derivative) control algorithm was implemented to acquire and precisely control the temperature. We also discuss how the instrument is calibrated. The device was tested successfully for the amplification of T. pallidum (Syphilis) bacterial DNA and Zika virus RNA samples, showing similar performance to a commercial PCR instrument.


Assuntos
Infecção por Zika virus , Zika virus , Algoritmos , Calefação , Temperatura Alta , Humanos , Reação em Cadeia da Polimerase , Temperatura
9.
Eur Spine J ; 30(1): 227-231, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32844255

RESUMO

INTRODUCTION: Ultrasonography has been used to understand the functional and biomechanical aspects of the lumbar multifidus muscle in vivo. To characterize the multifidus echogenicity, the peculiarities of their superficial and deep layers must be considered. PURPOSE: The present paper aimed to characterize the lumbar multifidus echo intensity (EI), in both superficial and deep layers, in ultrasonography images acquired in longitudinal and transversal orientations. METHODS: Evaluator obtained two images in each side of the lumbar of the volunteer, who was lying on prone position. Ultrasonography images were taken with probe in transversal and longitudinal orientations. EI was estimated by means average value of the grayscale distribution histogram, by extracting from region of interest of the superficial and deep layer. All participants returned for a second test day. Two-way MANOVA test was applied to compare EI measurements, considering layers and side factors. The reliability and variability were analyzed by the intraclass correlation coefficient and standard error measurements (SEM), respectively. Two-way MANOVA found significant difference between the layers in the transversal and longitudinal images, but not between the sides. RESULTS: Interdays reliability ranged of reasonable to excellent, and SEM values were lower than 17.08%. The superficial layer of the multifidus muscle showed higher EI values than the deeper one. CONCLUSIONS: These analyses can serve as a basis for future studies approaching multifidus of the people with low back pain.


Assuntos
Dor Lombar , Músculos Paraespinais , Humanos , Dor Lombar/diagnóstico por imagem , Região Lombossacral/diagnóstico por imagem , Músculos Paraespinais/diagnóstico por imagem , Reprodutibilidade dos Testes , Ultrassonografia
10.
Acta Ortop Bras ; 28(4): 190-194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32788862

RESUMO

OBJECTIVE: To compare the mechanical properties of the supraspinatus tendon in different age groups using Supersonic Shearwave Imaging (SSI) elastography. METHODS: We evaluated 38 healthy individuals of both genders, 20 being in the range of 20 to 35 years and 18 being over 60 years. The shear modulus of the supraspinatus tendon was measured by SSI elastography, always on the right side. Means between age groups were compared and statistically analyzed using the Shapiro-Wilk normality test followed by the student's t-test and were established as a statistically significant value of p ≤ 0.05. RESULTS: A statistically significant difference was observed when the mean values of the shear modulus of the supraspinatus tendon of young adults (23.98 ± 9.94 KpA) were compared with those of older adults (17.92 ± 6.17 KpA). CONCLUSION: We found a difference between the means of the shear modulus measured by the SSI elastography, showing a significant decrease of the shear modulus with the chronological age progression. Level of Evidence III, Diagnostic Studies - Investigating a Diagnostic Test.


OBJETIVO: Comparar as propriedades mecânicas do tendão supraespinal em diferentes grupos etários, utilizando a elastografia Supersonic Shearwave Imaging (SSI). MÉTODOS: Foram avaliados 38 indivíduos saudáveis de ambos os sexos, sendo 20 na faixa de 20 a 35 anos e 18 acima dos 60 anos de idade. Foi aferido o módulo de cisalhamento do tendão supraespinal por elastografia SSI, sempre do lado direito. As médias entre os grupos etários foram comparadas e analisadas estatisticamente, sendo utilizado o teste de normalidade Shapiro-Wilk seguido do student t-test e estabelecido como valor de significância estatística um p ≤ 0,05. RESULTADOS: Foi evidenciada diferença estatisticamente significativa quando comparadas as médias do módulo de cisalhamento do tendão supraespinal dos adultos jovens (23,98 ± 9,94 KpA) com a dos idosos (17,92 ± 6,17 KpA). CONCLUSÃO: Houve diferença entre as médias do módulo de cisalhamento medido pela elastografia com SSI, demonstrando diminuição significativa do módulo de cisalhamento com a progressão da idade cronológica. Nível de Evidência III, Estudos diagnósticos - Investigação de um exame para diagnóstico.

11.
Toxicology ; 436: 152428, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32151602

RESUMO

The increase in human infertility prevalence due to male reproductive disorders has been associated with extensive endocrine-disrupting chemical (EDC) exposure. Acrylamide (AA) is a compound formed spontaneously during heat processing of some foods that are mainly consumed by children and adolescents. In this study, we evaluated the prepubertal AA exposure effects on male adult reproductive physiology using a prepubertal experimental model to analyze the pubertal development, spermatogenesis hormones levels and genes expression involved in male reproductive function. This study is the first one to use the validated protocol to correlate the AA exposure with puberty development, as well as the AA-induced endocrine disrupting effects on reproductive axis. AA did not affect the age at puberty, the reproductive organ's weight and serum hormonal levels. AA reduces spermatogenesis, induces morphological and functional defects on sperm and alters transcript expression of sexual hormone receptors (Ar and Esr2), the transcript expression of Tnf, Egr2, Rhcg and Lrrc34. These findings suggest that excessive AA consumption may impair their reproductive capacity at adulthood, despite no changes in hormonal profile being observed.


Assuntos
Acrilamida/toxicidade , Disruptores Endócrinos/toxicidade , Contaminação de Alimentos , Infertilidade Masculina/induzido quimicamente , Desenvolvimento Sexual/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Fatores Etários , Animais , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Relação Dose-Resposta a Droga , Proteína 2 de Resposta de Crescimento Precoce/genética , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratos Wistar , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Medição de Risco , Espermatozoides/metabolismo , Espermatozoides/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
J Surg Oncol ; 121(5): 730-742, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31845348

RESUMO

BACKGROUND: Approximately 70% of cancer-related deaths occur in low- and middle-income countries. In addition to social and racial inequalities, treatment options in these countries are usually limited because of the lack of trained staff and equipment, limited patient access to health services, and a small number of clinical guidelines. OBJECTIVES: The Brazilian Society of Surgical Oncology developed this guideline to address these barriers and guide physicians treating patients with endometrial cancer (EC) in regions with limited resources and few specialized centers. METHODS: The guideline was prepared from 10 January to 25 October 20192019 by a multidisciplinary team of 56 experts to discuss the main obstacles faced by EC patients in Brazil. Thirteen questions considered critical to the surgical treatment of these patients were defined. The questions were assigned to groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments for presentations in meetings, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including staging, fertility spearing treatment, genetic testing, sentinel lymph node use, surgical treatment, and other clinical relevant questions, major agreement was achieved by the participants, always using accessible alternatives. CONCLUSIONS: It is possible to provide adequate treatment for most EC patients in resource-limited areas, but the first option should be referral to specialized centers with more resources.


Assuntos
Países em Desenvolvimento , Neoplasias do Endométrio/cirurgia , Acessibilidade aos Serviços de Saúde , Brasil , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Continuidade da Assistência ao Paciente , Diagnóstico por Imagem , Neoplasias do Endométrio/patologia , Feminino , Preservação da Fertilidade , Humanos , Histerectomia , Excisão de Linfonodo , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/terapia , Exame Físico , Encaminhamento e Consulta , Biópsia de Linfonodo Sentinela , Sociedades Médicas
13.
Trials ; 20(1): 661, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783777

RESUMO

BACKGROUND: Denture-related stomatitis (DS) is chronic multifactorial inflammation, strongly related to the presence of the biofilm that is the complex structure formed by microorganisms held together by a mucus-like matrix of carbohydrate that adheres to different surfaces, including the denture surface. DS has recently been correlated with deleterious cardiovascular alterations. The potential effect of hygiene protocols in the control of DS and randomized clinical trials that address this oral condition with cardiovascular complications are important in clinical decision-making. MATERIAL/DESIGN: A clinical trial, randomized, double-blind, and with parallel groups, will be conducted in Brazil The sample will consist of 100 patients without teeth in both arches, users of at least maxillary complete dentures, and diagnosed with DS, who will be allocated to groups (n = 25 per group) according to the different hygiene protocols: (1) brushing of the palate and immersion of the prosthesis in 0.25% sodium hypochlorite solution (positive control); (2) brushing of the palate and immersion of the prosthesis in 0.15% triclosan solution; (3) brushing of the palate and immersion of the prosthesis in lactose monohydrate; or (4) brushing the palate with citric acid and immersing the prosthesis in lactose monohydrate. The response variables will be heart rate variability and alteration of blood pressure (systemic level), remission of DS, removal of biofilm, reduction of microbial load (colony-forming units (CFU)), mouth and prosthesis odor level, expression of MUC1, proinflammatory cytokines, C-reactive protein (CRP), viscosity, pH and salivary flow (locally); patient-centred qualitative analysis will also be undertaken. Measurements will be performed at baseline and 10 days after the interventions. The results obtained will be statistically analyzed as pertinent, with a level of significance of 0.05. DISCUSSION: This study will provide a guideline for clinical practice regarding the use of hygiene protocols in the treatment of oral diseases (DS) mediated by biofilm. Also, it may provide evidence of correlation of oral manifestation with cardiac risk. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials, RBR-4hhwjb. Registered on 9 November 2018.


Assuntos
Higiene Bucal , Ensaios Clínicos Controlados Aleatórios como Assunto , Estomatite sob Prótese/terapia , Biofilmes , Método Duplo-Cego , Frequência Cardíaca , Humanos , Estomatite sob Prótese/fisiopatologia
14.
J Sports Med Phys Fitness ; 59(1): 42-49, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29308844

RESUMO

BACKGROUND: The purpose of this study was to compare traditional strength training (TST) versus complex and contrast training (CCT) on sprint, change of direction speed (COD) and squat jump (SJ) in young male soccer players. METHODS: Twenty-two soccer players (age: 18.4±0.4 years, body mass: 70.2±9.1 kg, height: 179.9±7.5 cm), were randomly assigned to one of two groups: TST (N.=12) and CCT (N.=10). The study was conducted using a randomized experimental design over an eight-week period. The participants assigned to the CCT group performed high-power exercises paired with high-velocity exercises. The participants assigned to the TST group performed resistance exercises in a straight-set forma. During the study period, sprint tests for 5, 10, 20 and 30 m split times, COD and SJ were applied. A two-way ANOVA was applied, and the alpha level was P<0.05. RESULTS: The results demonstrated that the CCT regimen elicited significant within-group differences in 5 m sprint time (1.032 s to 0.997 s, pre- and postintervention, respectively, effect size (ES) = -0.5, medium; P=0.04), COD (5.963 s to 5.639 s, pre- and postintervention, respectively, ES -2.7, large; P<0.001) and SJ (30.9 cm to 34.4 cm, pre- and postintervention, respectively, ES =0.8, large; P<0.001). Conversely, the TST did not elicit significant within-group differences for any of the dependent variables. No differences were found between groups at the post-test time point. CONCLUSIONS: In conclusion, the CCT protocol could be used to improve sprint, COD and SJ in male soccer players.


Assuntos
Desempenho Atlético , Treinamento Resistido/métodos , Futebol/fisiologia , Adolescente , Análise de Variância , Teste de Esforço , Humanos , Masculino , Corrida
15.
Zootaxa ; 4496(1): 503-516, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30313719

RESUMO

The Campos Gerais region of Paraná are on an ancient plateau of sandstone origin and are covered with a diverse vegetation including mainly grasslands and various types of Atlantic Forest (particularly Araucaria forest). The region represents an important natural capital for biodiversity conservation as well as for agricultural and forestry production. However, little is known of the species richness and diversity of soil macroinvertebrates in this region. In the present study we evaluated earthworm species occurrence and richness in five land use systems (LUS) in the southern part of the Campos Gerais in Lapa county. Earthworms were handsorted from up to 18 soil monoliths on five occasions over three years (Feb. 2014, Feb., Mar., Nov. 2015, Jul. 2016) in the following LUS: old native forest, native grassland, young regenerating forest and grass lawn in the Uru Reserve and annual crop fields (soybean) in neighboring private farms (not all systems were sampled on all occasions). Nine earthworm species belonging to four families and five genera were found, of which six were native and three exotic species (Dichogaster gracilis, Amynthas gracilis, A. corticis). Of the native species, Urobenus brasiliensis and Andiorrhinus duseni (a large bodied-worm) are already well known from S and SE Brazil, while the remaining four were new species that require further description (Fimoscolex n.sp.1 and n.sp.2, Glossoscolex n.sp.1 and n.sp.2). In general, more species were found in February (summer) than March and November. The cropping system (soybean) had the lowest abundance and species richness in relation to other sites, although in the young and old forests no earthworms were found on some sample dates. Given the several new species found in this small reserve, and the relatively few sites studied thus far in the Campos Gerais, further efforts are needed to adequately characterize the earthworm fauna of the region, from which many other species are expected.


Assuntos
Oligoquetos , Agricultura , Animais , Biodiversidade , Brasil , Florestas
16.
PeerJ ; 4: e2329, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27602293

RESUMO

The maintenance of species diversity is a central focus in ecology. It is not rare to observe more species than the number of limiting resources, especially in plankton communities. However, such high species diversity is hard to achieve in theory under the competitive exclusion principles, known as the plankton paradox. Previous studies often focus on the coexistence of predefined species and ignore the fact that species can evolve. We model multi-resource competitions using evolutionary games, where the number of species fluctuates under extinction and the appearance of new species. The interspecific and intraspecific competitions are captured by a dynamical payoff matrix, which has a size of the number of species. The competition strength (payoff entries) is obtained from comparing the capability of species in consuming resources, which can change over time. This allows for the robust coexistence of a large number of species, providing a possible solution to the plankton paradox.

17.
Am J Dent ; 29(3): 149-53, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27505991

RESUMO

PURPOSE: To evaluate the in vitro antimicrobial efficacy of alkaline peroxides against microbial biofilms on acrylic resin surfaces. METHODS: Denture base acrylic resin (Lucitone 550; n= 360) circular specimens (15 x 3 mm) were obtained from a circular metal matrix and sterilized with microwave irradiation (650 W, 6 minutes). The specimens were then contaminated with suspensions [106 colony-forming units (CFU)/mL] of Candida albicans (Ca), Candida glabrata (Cg), Staphylococcus aureus (Sa), Streptococcus mutans (Sm), Bacillus subtilis (Bs), Enterococcus faecalis (Ef), Escherichia coli (Ec), and Pseudomonas aeruginosa (Pa). After contamination, the specimens were incubated at 37 degrees C for 48 hours and then placed in a stainless steel basket, which was immersed in a beaker with one of the following solutions prepared and used according to the manufacturers' instructions (n= 10 per group): Group PC (positive control), phosphate-buffered saline (PBS) solution; Group MI, NitrAdine, Medical Interporous; Group EF, Efferdent Plus; Group CT, Corega Tabs; and Group NC (negative control; n= 5), no contamination and immersed in PBS. After incubation (37 degrees C, 24 hours), the number of colonies with characteristic morphology was counted, and CFU/mL values were calculated. The data were processed following the transformation into the formula log" (CFU + 1) and statistically analyzed by the Kruskal-Wallis and Dunn's tests (alpha = 0.05). RESULTS: There were significant differences between the groups for the evaluated microorganisms with a significant reduction in the CFU/mL. MI was effective for Ca, Cg, Sa, Sm, Ef, Ec and Pa; EF was effective for Cg, Sm, Ef, Ec and Pa; and CT was effective for Sa, Bs and Ec, when compared with the PC group.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Dentaduras/microbiologia , Desinfecção , Biofilmes , Contagem de Colônia Microbiana , Bases de Dentadura
18.
J Sports Med Phys Fitness ; 56(11): 1269-1278, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26609969

RESUMO

BACKGROUND: The purpose of this study was to compare traditional strength training (TST) and complex contrast training (CCT) on the repeated-shuttle-sprint ability (RSSA), the countermovement squat jump (CMJ) height, the one repetition maximum (1RM) at squat on the Smith machine, and on muscle architecture in young, male elite soccer players. METHODS: Twenty-two soccer players (mean age 18.4±0.4 years; mean weight 70.2±9.1 kg; mean height 179.9±7.5 cm) who belonged to the under-20 age group were randomly assigned into two groups: CCT (N.=10) or TST (N.=12). During the study period, the soccer players trained with CCT through power exercises performed before high-velocity exercises and TST based on a set-repetition format through daily, undulatory periodization. RESULTS: After statistical analysis (P<0.05), the results demonstrated that the specific CCT regimen provided a significant improvement in the RSSA percent decrement (moderate effect size), CMJ (large effect size) and 1RM ability (large effect size). However, the TST promoted significant changes in 1RM (large effect size) and a significant increase in the muscle thickness of the vastus intermedius (moderate effect size). CONCLUSIONS: The CCT protocol could be used to improve the RSSA parameters, CMJ and 1RM, and the TST developed dynamic strength and muscle growth. Coaches can choose either CCT or TST protocols according to the needs of their soccer players.


Assuntos
Força Muscular/fisiologia , Treinamento Resistido , Corrida/fisiologia , Futebol , Adolescente , Desempenho Atlético/fisiologia , Exercício Físico , Humanos , Masculino , Músculo Quadríceps , Treinamento Resistido/métodos , Adulto Jovem
19.
Genome Announc ; 2(6)2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25414513

RESUMO

We report the genome, in a single chromosome, of Lactococcus lactis strain AI06, isolated from the mesocarp of the açaí fruit (Euterpe oleracea) in eastern Amazonia, Brazil. This strain is an endophyte of the açaí palm and also a component of the microbiota of the edible food product.

20.
PLoS One ; 8(6): e66495, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23840490

RESUMO

The effects of habitat fragmentation and their implications for biodiversity is a central issue in conservation biology which still lacks an overall comprehension. There is not yet a clear consensus on how to quantify fragmentation even though it is quite common to couple the effects of habitat loss with habitat fragmentation on biodiversity. Here we address the spatial patterns of species distribution in fragmented landscapes, assuming a neutral community model. To build up the fragmented landscapes, we employ the fractional Brownian motion approach, which in turn permits us to tune the amount of habitat loss and degree of clumping of the landscape independently. The coupling between the neutral community model, here simulated by means of the coalescent method, and fractal neutral landscape models enables us to address how the species-area relationship changes as the spatial patterns of a landscape is varied. The species-area relationship is one of the most fundamental laws in ecology, considered as a central tool in conservation biology, and is used to predict species loss following habitat disturbances. Our simulation results indicate that the level of clumping has a major role in shaping the species-area relationship. For instance, more compact landscapes are more sensitive to the effects of habitat loss and speciation rate. Besides, the level of clumping determines the existence and extension of the power-law regime which is expected to hold at intermediate scales. The distributions of species abundance are strongly influenced by the degree of fragmentation. We also show that the first and second commonest species have approximately self-similar spatial distributions across scales, with the fractal dimensions of the support of the first and second commonest species being very robust to changes in the spatial patterns of the landscape.


Assuntos
Biodiversidade , Ecossistema , Conservação dos Recursos Naturais
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