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Metals and metalloids including lead (Pb), arsenic (As) and manganese (Mn) can occur as mixtures in occupational contexts, such as mines. These chemicals are all known to be neurotoxic and provoke changes in heme metabolism also known to induce neurotoxicity. The objective of this work was to propose a multi-biomarker (BM) methodology to screen subjects exposed to the mixture of Pb, As and Mn and assess the severity of their exposure/effects, in an individual basis. The urinary levels of the metals, dela-aminolevulinic acid (ALA) and porphyrins were determined in Portuguese miners and in a control group. The combination of Pb and As urinary levels had the highest capability to identify subjects occupationally exposed to this mixture in mines, as evaluated through Receiver Operating Characteristic (ROC) (A = 98.2%; p < 0.05), allowing that 94.2% of 86 studied subjects were properly identified and the generation of an equation indicating the odd of a subject be considered as exposed to the metal mixture. The combination of urinary ALA and porphyrins revealed to be best one to be applied in the assessment of subjects with high, intermediate, and low magnitudes of exposure/effects, with 95.7% of 46 miners classified correctly according to their severity sub-group and allowing to generate equations, which can be applied in new subjects. The proposed methodology showed a satisfactory performance, evaluating in an integrated manner the magnitude of exposure/effects of the exposed workers, may contributing to improve the control of their health.
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Arsênio/efeitos adversos , Monitoramento Biológico , Biomarcadores Ambientais , Poluentes Ambientais/efeitos adversos , Chumbo/efeitos adversos , Manganês/efeitos adversos , Exposição Ocupacional/efeitos adversos , Ácido Aminolevulínico/urina , Arsênio/urina , Poluentes Ambientais/urina , Humanos , Chumbo/urina , Manganês/urina , Mineração , Saúde Ocupacional , Porfirinas/urina , Valor Preditivo dos Testes , Medição de Risco , UrináliseRESUMO
BACKGROUND: The cryopreservation and recovery of epididymis tail sperm is an important biotechnology dependent on the composition of the freezing medium. OBJETIVE: To evaluate the effect of melatonin, added to commercial freezing medium extender, on the kinetics and viability of bovine epididymis tail sperm. MATERIAL AND METHODS: Five routines were performed, each consisting of eight epididymis and the structures were sliced onto a glass plate containing a commercial diluting medium for Botubov. The samples were divided into four groups, with 80 x 106 spermatozoa per mL. Group 1: samples diluted in Botubov. Group 2: samples centrifuged (600 g, 10 min), and the pellet re-suspended in Botubov. Group 3, samples diluted in Botubov containing 100 pM melatonin. Group 4: samples centrifuged (600 g, 10 min) and the pellet resuspended in Botubov with 100 pM melatonin. The samples were transferred to 0.5 mL straws at 40 x 106 viable spermatozoa, stabilized at 5º C for 4 h, transferred to liquid nitrogen vapour for 20 min, dipped in liquid nitrogen and stored in a cryogenic cylinder. After thawing (46ºC, 15s), sperm kinetics and viability parameters were evaluated. RESULTS: There was no difference in the parameters of total motility (MT, %), progressive motility (MP, %), progressive linear velocity (VSL, µm/s), curvilinear velocity (VCL, µm/s), linearity (LIN, %), spermatozoa with rapid movement (RAP, %) and level of intact plasma membranes and acrosome (IPMA, %) among the groups studied. However, a difference was observed between the routines performed. CONCLUSION: The protocol for freezing bovine epididymis tail sperm is applicable; however, there is an influence of the epididymis used, for the best efficacy of this biotechnology.
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Antioxidantes , Criopreservação/veterinária , Preservação do Sêmen , Animais , Antioxidantes/farmacologia , Bovinos , Crioprotetores/farmacologia , Epididimo/citologia , Masculino , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , EspermatozoidesRESUMO
Pesticides are used worldwide to control arthropod parasites in cattle herds. The indiscriminate and/or inappropriate use of pesticides without veterinary guidance is a reality in several countries of South America. Improper pesticide use increases the chances of contamination of food and the environment with chemical pesticides and their metabolites. Reduction of these contamination events is an increasing challenge for those involved in livestock production. The horn fly, Haematobia irritans (Linnaeus) (Diptera: Muscidae), is one of the most economically important parasites affecting cattle herds around the world. As such, horn fly control efforts are often required to promote the best productive performance of herds. Pesticide susceptibility bioassays revealed that pyrethroid resistance was widespread and reached high levels in horn fly populations in the Brazilian state of Rondônia. The knockdown resistance (kdr) sodium channel gene mutation was detected in all horn fly populations studied (n = 48), and the super kdr sodium channel gene mutation was found in all homozygous resistant kdr individuals (n = 204). Organophosphate resistance was not identified in any of the fly populations evaluated.
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Resistência a Inseticidas/genética , Inseticidas/farmacologia , Muscidae/efeitos dos fármacos , Organofosfatos/farmacologia , Piretrinas/farmacologia , Animais , Brasil , Muscidae/genéticaRESUMO
BACKGROUND: The chromosomal microarray analysis (CMA) is recommended as a first-tier test for individuals with developmental delay (DD)/intellectual disability (ID) and/or multiple congenital anomalies. However, owing to high costs, this technique is not widely performed for diagnostic purposes in several countries. The aim of this study was to identify clinical features that could favour the hypothesis of genomic imbalances (GIs) in individuals with DD/ID. METHODS: The sample consisted of 63 individuals, and all of them underwent a detailed evaluation by a clinical geneticist and were investigated by the CMA. They were divided into two groups. Group A composed of 20 individuals with pathogenic copy number variants (CNVs); and group B composed of 43 individuals with normal CMA results or variants of uncertain clinical significance (VUS). RESULTS: Pathogenic GIs were found in 20 cases (32%), including 11 individuals with an abnormal karyotype, VUS was found in five individuals (8%) and the results were normal in 38 individuals (60%). Major anomalies were found in 15/20 (75%) individuals in group A against 35/43 (81%) in group B. Dysmorphisms (≥5) were found in 17/20 (85%) in group A and 41/43 (95%) in group B. The most frequent major anomalies detected in group A were congenital heart disease, epilepsy and renal malformation; and in group B, they were malformations of central nervous system, congenital heart disease, microcephaly, epilepsy and hearing impairment. There was no significant statistical difference among the frequencies in groups A and B. CONCLUSIONS: Evidences point that every individual with DD/ID, with no specific clinical suspicion, should have screening for GIs as a first-tier test, regardless of the presence or absence of additional major anomalies or dysmorphisms. Future studies with a similar design would be helpful, especially in countries where the access to new technologies is still limited.
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Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/genética , Variação Estrutural do Genoma/genética , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Fenótipo , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Análise em Microsséries , Adulto JovemRESUMO
The aim of this study was to assess the effects of repeated applications of antimicrobial photodynamic therapy (aPDT) on the non-surgical periodontal treatment of residual pockets. This work was performed and reported according to the Cochrane and PRISMA recommendations, respectively, and registered at the PROSPERO registry (number CRD42017058403). An extensive search of the biomedical literature was conducted on four databases from January 1960 to August 2018, followed by hand searching. Analysis of the quality of the selected studies was based on the risk of bias. Only two randomised controlled clinical trials (RCTs) met the inclusion criteria although they had unclear risk of bias. One study showed that repeated applications of aPDT in association with conventional non-surgical treatment during periodontal maintenance improved all clinical outcomes after 6 months. The other study, which assessed the effects of repeated applications of aPDT in association with ultrasound debridement on periodontal pathogens, showed no significant reduction of the main pathogens after 3-6 months but reported reductions of probing pocket depth and C-reactive protein after 3 and 6 months, respectively, compared to mechanical therapy alone. Concluding, it was not possible to state that repeated applications of aPDT, in association with non-surgical treatment of residual pockets, have effective clinical effects in the periodontal maintenance therapy. Although one can consider that aPDT is a promising adjuvant therapy, it is still necessary to carry out more RCTs with low risk of bias in order to confirm or refute the benefits of multiple applications for residual periodontal pockets.
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Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Bolsa Periodontal/tratamento farmacológico , Fotoquimioterapia , Adulto , Idoso , Antibacterianos/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Viés de Publicação , Fatores de Risco , Resultado do TratamentoRESUMO
WHAT IS KNOWN AND OBJECTIVE: Elderly people are the principal consumers of prescription drugs. The more the medication used by the patient, the greater the likelihood there is of the patient being subjected to potentially inappropriate drug therapy (PIDT). PIDT has been measured in the literature with both implicit and explicit tools. The purpose of this review was to assess the use of tools to detect PIDT in various studies and to determine which terms are used to refer to PIDT in practice. METHODS: A systematic review was conducted according to the following steps: the first was identification. In this step, studies were selected from different combinations of the descriptors 'aged', 'elderly', 'inappropriate prescribing' and 'drug utilization' in three different languages, using the Embase, Medline, Scielo, Scopus and Web of Science databases. Second, the papers that satisfied the inclusion criteria for data extraction were carefully examined by three evaluators to determine the tools used and terms that referred to PIDT. RESULTS AND DISCUSSION: From the combinations of keywords, 8610 articles were found. At the end of the selection process, 119 of the articles complied with the specified criteria. The degree of agreement among evaluators was moderate for the study titles (κ1 = 0·479) and substantial for abstracts (κ2 = 0·647). With respect to the PIDT evaluation criteria used by the studies, 27·7% used two criteria. Of the 27 evaluation criteria identified, the Beers criteria were used by 82·3% of the studies. More than 50 different terms to identify PIDT were found in the literature. WHAT IS NEW AND CONCLUSION: This review is the first study to conceptualize and discuss terms that refer to PIDT. At present, there is no consensus regarding terms used to refer to PIDT, with over 50 different terms currently in use. This review shows an increase in the number of articles aimed at evaluating PIDT using implicit and explicit tools.
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Uso de Medicamentos/estatística & dados numéricos , Prescrição Inadequada/estatística & dados numéricos , Polimedicação , Padrões de Prática Médica/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Idoso , Bases de Dados Factuais/estatística & dados numéricos , HumanosRESUMO
Although the anti-caries effects of standard fluoride (F) toothpastes are well established, their use by preschoolers (2- to 5-year-olds) has given rise to concerns regarding the development of dental fluorosis. Thus, a widespread support of low F toothpastes has been observed. The aim of this study was to assess the effects of low (<600 ppm) and standard (1,000-1,500 ppm) F toothpastes on the prevention of caries in the primary dentition and aesthetically objectionable (moderate to severe) fluorosis in the permanent dentition. A systematic review of clinical trials and meta-analyses were carried out. Two examiners independently screened 1,932 records and read 159 potentially eligible full-text articles. Data regarding characteristics of participants, interventions, outcomes, length of follow-up and potential of bias were independently extracted by two examiners and disagreements were solved by consensus after consulting a third examiner. In order to assess the effects of low and standard F toothpastes on the proportion of children developing caries and fluorosis, pooled relative risks (RR) and associated 95% confidence intervals were estimated using a fixed and a random-effects model, respectively. Five clinical trials fulfilled the inclusion criteria. Low F toothpastes significantly increased the risk of caries in primary teeth [RR = 1.13 (1.07-1.20); 4,634 participants in three studies] and did not significantly decrease the risk of aesthetically objectionable fluorosis in the upper anterior permanent teeth [RR = 0.32 (0.03-2.97); 1,968 participants in two studies]. There is no evidence to support the use of low F toothpastes by preschoolers regarding caries and fluorosis prevention.
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Cariostáticos/administração & dosagem , Cárie Dentária/prevenção & controle , Fluoretos/administração & dosagem , Fluorose Dentária/prevenção & controle , Cremes Dentais/uso terapêutico , Criança , Pré-Escolar , Humanos , Dente Decíduo/efeitos dos fármacosRESUMO
In this paper, we show that both continuous phase transitions of liquid water, the liquid-gas and the liquid-liquid, can be articulated within a single thermodynamic analytical formalism. This result follows from a combination of the two-liquid model (TLM), recently confirmed for water, with the idea of a thermal-dependent excluded volume, ve, concept introduced by van der Waals, in his famous state equation. Starting from the fundamentals of thermodynamics, it will be shown that the TLM naturally leads to the idea of an extensive thermal-dependent ve that acts as a parameter of the sample thermodynamic potentials. This procedure effectively separates the thermodynamics of the system into two parts: the first concerns the clusters' thermodynamics, taken as wandering particles, and the second concerns the thermal behavior of its internal structure (geometry and number of particles). From this result, we demonstrate that the condition of mechanical instability leads to not one but two critical points, each happening in one of the above-described parts of the system.
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Nowadays, there is an increased consumption of plant-based protein beverages like soy beverages (SBs) as substitutes for cow milk (CM). Both accumulate toxic metals like lead (Pb), cadmium (Cd), and manganese (Mn), which, although essential, are neurotoxic at high levels. Metals can also perturb the normal development of children. This work aimed to evaluate these metal concentrations in CM and SB purchased on the Portuguese market. After validation of the method, linearity of calibration curves, work range, detection and quantification limits, and selectivity, metals were determined in 14 CM and 14 SB brands using atomic absorption spectrometry. The values were compared between CM and SB and with permissible limit values. Soy beverages had significantly (p < 0.05) higher concentrations of Cd (5.6 ± 4.2 µg/L) and Mn (117.4 ± 30.3) µg/L) than CM (2.15 ± 1.84 µg/L and 5.93 ± 1.21 µg/L, respectively); the Pb concentrations in CM (19.3 ± 12.1 µg/L) were not significantly (p > 0.05) higher than in SB (13.4 ± 9.6 µg/L). These values were similar to other studies and close to but under permissible limit values. Nevertheless, due to the toxicity and bioaccumulation of metals, the fact that these foods are routinely ingested by all ages, mainly children, and represent key ingredients in many processed foods, including baby foods, we suggest strict surveying of metal levels in CM and SBs.
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INTRODUCTION: This scoping review aimed to map the evidence about the microbiota found in persistent endodontic infections. METHODS: The study protocol was prospectively registered and is available at https://osf.io/3g2cp. The electronic search was performed in MEDLINE via PubMed, Lilacs, BBO, Scopus, Web of Science, Cochrane Library, and Embase. The eligibility criteria were based on the PCC acronym, where P (Population) represents patients with teeth presenting persistent endodontic infection, C (Concept) represents microbial profile, and C (Context) represents undergoing endodontic retreatment. Clinical studies that evaluated the microbial profile of samples collected from root canals of teeth undergoing retreatment, using classical or molecular methods, were included. Studies that did not show a minimum period of 1 year between primary endodontic treatment and retreatment or did not radiographically evaluate the quality of primary root canal filling were excluded. Two reviewers independently selected the articles and collected data. RESULTS: From a total of 957 articles, 161 were read in full, and 32 studies were included. The most prevalent species were Enterococcus faecalis, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Dialister invisus, Propionibacterium acnes, Tannerella forsythia, and Treponema denticola. Cases with symptomatology or inadequate root canal filling presented an increase in specific bacterial species compared to those with no symptomatology or adequate filling. A greater number of microorganisms was observed in teeth with inadequate coronal restoration compared to those with adequate restoration. CONCLUSIONS: Persistent endodontic infections have a polymicrobial profile identified by the commonly used methods for bacterial detection/identification and are subject to the limitations present in each of those methods.
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Cavidade Pulpar , Porphyromonas gingivalis , Humanos , Cavidade Pulpar/microbiologia , Prevotella intermedia , Porphyromonas endodontalisRESUMO
We evaluated the phenology and reproductive phenological diversity of three sympatric species of Miconia in a gallery forest in the Chapada Diamantina mountains, Bahia, Brazil. The reproductive phenophases (bud, flower, immature fruit, and mature fruit) of M. alborufescens (N=38), M. holosericea (N=46), and M. prasina (N=44) were evaluated monthly, between June/2008 and June/2015. The Fournier index was used to assess the intensities of the reproductive phenophases; synchrony and seasonality were analyzed using circular statistics and the Rayleigh (Z) test. The Frideman and Wilcoxon tests were used to verify interannual variations in phenological patterns. Reproductive phenological diversity was measured by calculating the Shannon-Wiener index; ANOVA tested possible differences in the means of diversity among the different years. The reproductive phenophases of the studied Miconia species occurred sequentially (M. alborufescens, then M. holoserica, followed by M. prasina), in the transition between the dry and rainy seasons, with little overlap between them. In general, the species showed seasonal and synchronic phenological patterns, with some variations that coincided with El Niño and/or La Niña events, e.g., demonstrating changes in the periodicity, synchrony, and intensity of their phenophases. The intensity of fruiting, for example, showed increases during La Niña years. Reproductive phenological diversity appears to respond to climate changes resulting from El Niño events and periods of prolonged drought, with high Shannon-Wiener index values. The results also suggest that the effects of global climatic phenomena (El Niño and La Niña) that alter regional climatic seasonality can also cause variations in the reproductive phenological rhythms of the Miconia species studied.
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Melastomataceae , Floresta Úmida , Estações do Ano , Florestas , Chuva , El Niño Oscilação SulRESUMO
Chronic, excessive exposure to manganese (Mn) may induce neurotoxicity and cause an irreversible brain disease, referred to as manganism. Efficacious therapies for the treatment of Mn are lacking, mandating the development of new interventions. The purpose of the present study was to investigate the efficacy of ebselen (Ebs) and para-aminosalicylic acid (PAS) in attenuating the neurotoxic effects of Mn in an in vivo rat model. Exposure biomarkers, inflammatory and oxidative stress biomarkers, as well as behavioral parameters were evaluated. Co-treatment with Mn plus Ebs or Mn plus PAS caused a significant decrease in blood and brain Mn concentrations (compared to rats treated with Mn alone), concomitant with reduced brain E2 prostaglandin (PGE2) and enhanced brain glutathione (GSH) levels, decreased serum prolactin (PRL) levels, and increased ambulation and rearing activities. Taken together, these results establish that both PAS and Ebs are efficacious in reducing Mn body burden, neuroinflammation, oxidative stress and locomotor activity impairments in a rat model of Mn-induced toxicity.
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Ácido Aminossalicílico/farmacologia , Azóis/farmacologia , Manganês/toxicidade , Síndromes Neurotóxicas/prevenção & controle , Compostos Organosselênicos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Isoindóis , Masculino , Manganês/farmacocinética , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Distribuição TecidualRESUMO
In a protocol for the resynchronization of ovulation starting 14 days (D14) after timed artificial insemination, the effects of short-action injectable progesterone (P4i) administration and the length of treatment with an intravaginal progesterone (P4) device on follicular dynamics, the conception rate (P/AI) and the percentage of false positives were evaluated in 1065 Nelore heifers previously timed-inseminated. On D14, P4 devices were inserted, and heifers allocated, based on a 2 × 2 factorial design, to receive (P4i) or not 50 mg of P4i (NoP4i), and to remove the P4 device after 6 (6Day) or 8 days (8Day). At the time of P4 device removal (D20 and D22), non-pregnancy diagnosis was performed using vascularization of the corpus luteum (VCL) evaluated. At this time, non-pregnant heifers received 150 µg of D-cloprostenol, 0.6 mg of estradiol cypionate and 300IU of eCG. TAI was performed 48 h after P4 device removal. For these heifers, ultrasound examinations were performed at P4 device removal and at TAI to evaluate follicular dynamics and at 30 days after TAI to evaluate the P/AI. Pregnant heifers based on VCL were evaluated using B-mode ultrasonography 10 days after Doppler ultrasound to evaluate the percentage of false positives. Statistical analyses were performed using the GLIMMIX procedure of SAS. There were no interaction effects between P4i and duration of treatment with a P4 device. The P/AI was diagnosed by Doppler, 1st TAI, 2nd TAI, total and percentage of false positives did not differ between heifers receiving or not P4i. Similarly, duration of treatment with a P4 device did not influence the P/AI by Doppler, 1st TAI, 2nd TAI and total. However, the percentage of false positives diagnoses was higher in 6Day heifers (P = 0.01). The diameter of largest follicle at P4 device removal was greater in the 8Day heifers (P = 0.001), and at TAI was higher in the P4i-treated heifers (P = 0.03). Additionally, the percentage of false positives diagnoses was lower in heifers that ovulated to the 1st TAI protocol (P = 0.001). In conclusion, for resynchronization 14 days after TAI, it is not necessary to inject P4i at the beginning of the protocol. In addition, P4 device removal after 6 instead of 8 days increases the percentage of false positives because of the earlier diagnosis (20 days after TAI), but does not interfere in P/AI of resynchronization protocol. Furthermore, the percentage of false positives is higher in heifers that did not ovulate to 1st TAI protocol.
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Sincronização do Estro , Progesterona , Bovinos , Animais , Feminino , Progesterona/farmacologia , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Ovulação , Corpo Lúteo , Estradiol/farmacologiaRESUMO
Global climate change, i.e. higher and more variable temperatures, and a gain in soil salinity are increasing plant stress with direct consequences on crop yield and quality levels. Rice productivity is strongly affected by abiotic stress conditions. The regulation of chromatin structure in response to environmental stress is poorly understood. We investigated the interphase chromatin organization from rice plants in non-stress versus stress conditions. We have used a cytogenetic approach, based on fluorescence in situ hybridization (FISH) with 45S, 5S rDNA and centromeric probes on rice tissue sections. The abiotic stress conditions included cold, heat and mild salinity and were applied during seed germination. In contrast to cold, saline and heat stresses caused extensive decondensation of 45S rDNA chromatin and also an increase in the distance between the 2 homologous 5S rDNA loci. 5-Azacytidine (5-AC), a DNA hypomethylating drug, greatly increased 45S rDNA chromatin decondensation and interestingly was able to induce polarization of centromeres in rice interphase nuclei. The abiotic stresses tested did not perturb the spatial position of centromeres, typically with circular arrangement around the nucleolus. The results suggest a role for chromatin plasticity in a world of climate changes.
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Metilação de DNA , Interfase/genética , Oryza/genética , Estresse Fisiológico/genética , Azacitidina/farmacologia , Centrômero/efeitos dos fármacos , Centrômero/genética , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Cromossomos de Plantas/efeitos dos fármacos , Cromossomos de Plantas/genética , Cromossomos de Plantas/metabolismo , Temperatura Baixa , DNA Ribossômico/genética , Temperatura Alta , Hibridização in Situ Fluorescente , Interfase/efeitos dos fármacos , Oryza/efeitos dos fármacos , Salinidade , Estresse Fisiológico/efeitos dos fármacosRESUMO
AIM: To develop a TaqMan probe-based, highly sensitive and specific quantitative PCR (qPCR) assay for the detection and quantification of Mycoplasma suis in the blood of pigs. METHODS AND RESULTS: Primers and probes specific to Myc. suis 16S rRNA gene were designed. The qPCR assay's specificity, detection limit, intra- and inter-assay variability were evaluated and its performance was compared with a Myc. suis conventional PCR assay (cPCR). Blood of two experimentally infected pigs, 40 Indiana pigs, 40 Brazilian sows and 28 peccaries were tested. The assay detected as few as ten copies of Myc. suis plasmids and was 100-fold more sensitive than the cPCR. No cross-reactivity with nontarget pig mycoplasmas was observed. An average of 1·62 × 10(11) and 2·75 × 10(8) target copies ml(-1) of blood were detected in the acutely and chronically infected pigs, respectively. Three (7·5%) pigs and 32 (80·0%) sows were positive while all peccaries were negative for Myc. suis. CONCLUSION: The developed qPCR assay is highly sensitive and specific for Myc. suis detection and quantification. SIGNIFICANCE AND IMPACT OF THE STUDY: TaqMan qPCR is an accurate and quick test for detection of Myc. suis infected pigs, which can be used on varied instrumentation platforms.
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Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Doenças dos Suínos/diagnóstico , Suínos/microbiologia , Animais , Brasil , Primers do DNA/genética , DNA Bacteriano/genética , Feminino , Indiana , Limite de Detecção , Mycoplasma/genética , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/genética , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Sus scrofa/microbiologia , Doenças dos Suínos/sangueRESUMO
The maturation kinetics and in vitro fertilization of immature bovine oocytes injected by the intra-follicular oocyte injection (IFOT) technique into pre-ovulatory follicles of previously synchronized cows were evaluated. In Experiment 1, grade I, II and III cumulus-oocyte complexes (COCs) were randomly distributed to one of three Groups: Matvitro22 (COCs matured in vitro for 22 h), MatFol20 and MatFol28 (COCs matured in vivo after being injected into a pre-ovulatory follicle of previously synchronized cows for 19.8 ± 0.1 h and 28.3 ± 0.1 h, respectively). Cows received 12.5 mg of LH (Lutropin, Bioniche, Canada) at the time of IFOT in the MatFol20 Group or 10 h after IFOT in the MatFol28 Group. MatFol20 and MatFol28 COCs were aspirated approximately 20 h after the LH injection for nuclear maturation kinetics and recovery rate assessment. In Experiment 2, grade I, II, and III COCs were randomly distributed into two Groups: Matvitro22 Group, COCs were matured and fertilized in vitro, and MatFol20 Group, COCs were matured as in the MatFol20 Group in Experiment 1, but COCs were fertilized in vitro. Putative zygotes were classified as fertilized, unfertilized or polyspermic. In Experiment 1, the recovery rate was lower (P < 0.001) in the MatFol20 Group (52.9%, 91/172) compared with MatFol28 (72.9%, 113/155). Rate of oocytes in germinal vesicle stage, metaphase I, anaphase I and telophase I were similar among Groups. However, oocytes matured in vivo for 28.3 h had lower rate of metaphase II (P = 0.001) and greater rates of degenerated (P = 0.001) and parthenogenetically activated (P = 0.001) oocytes. In experiment 2, the rates of polyspermy and degenerated were similar between Groups. However, the rate of fertilized oocytes was greater (P = 0.05) in oocytes in the MatFol20 Group. It is concluded that oocyte in vivo maturation for 19.8 h after IFOT does not compromise the nuclear maturation kinetics and increases in vitro fertilization rates. However, the extra 10 h of intra-follicular incubation time decreased oocyte viability.
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Fertilização in vitro , Oócitos , Animais , Bovinos , Feminino , Fertilização in vitro/veterinária , Cinética , Oogênese , Folículo OvarianoRESUMO
Intuition tells us that a rolling or spinning sphere will eventually stop due to the presence of friction and other dissipative interactions. The resistance to rolling and spinning or twisting torque that stops a sphere also changes the microstructure of a granular packing of frictional spheres by increasing the number of constraints on the degrees of freedom of motion. We perform discrete element modeling simulations to construct sphere packings implementing a range of frictional constraints under a pressure-controlled protocol. Mechanically stable packings are achievable at volume fractions and average coordination numbers as low as 0.53 and 2.5, respectively, when the particles experience high resistance to sliding, rolling, and twisting. Only when the particle model includes rolling and twisting friction were experimental volume fractions reproduced.
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[This corrects the article DOI: 10.1155/2019/4518742.].