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1.
Cryobiology ; 115: 104888, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508357

RESUMO

The experiment evaluated the effect of adding cholesterol-loaded cyclodextrin (CLC) to Prochilodus lineatus fish (Curimata) semen on post-thaw sperm quality. Twelve adult fish were used for sperm collection after induced spermiation with carp pituitary gland. The semen was diluted and treated with CLC in concentrations of 0 (control), 0.5, 1.0, 2.0, 3.0, and 4.0 mg for 120 × 106 spermatozoa/ml, loaded in 0.5 ml straws, packaged and placed in dry vapor vessel cylinders for 24 h before being submerged in liquid nitrogen for storage. The samples were thawed in a water bath at 60 °C for 8 s, and the sperm parameters evaluated were motility, activation duration, longevity, plasma membrane integrity, and morphology. Data were tested for normal distribution and ANOVA, followed by Friedman test (P < 0.05). Spermatozoa treated with CLC displayed higher motility than the control (P < 0.05). The duration of sperm activation was longer in sperm treated with 0.5, 1.0, and 2.0 mg of CLC than in control (P < 0.05). The membrane integrity was higher in sperm treated with 0.5, 1.0, 2.0, and 3.0 mg of CLC than in control and four mg-treated samples (P < 0.05). The sperm longevity and morphology alterations did not differ between treatments (P > 0.05). Adding 0.5, 1.0, or 2.0 mg of CLC in Prochilodus lineatus semen before cryopreservation improves sperm motility and membrane integrity.


Assuntos
Colesterol , Criopreservação , Crioprotetores , Ciclodextrinas , Preservação do Sêmen , Motilidade dos Espermatozoides , Espermatozoides , Animais , Masculino , Criopreservação/métodos , Criopreservação/veterinária , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Ciclodextrinas/farmacologia , Ciclodextrinas/química , Espermatozoides/efeitos dos fármacos , Colesterol/farmacologia , Crioprotetores/farmacologia , Membrana Celular/efeitos dos fármacos , Caraciformes , Análise do Sêmen
2.
Phys Chem Chem Phys ; 24(5): 3119-3128, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35040859

RESUMO

We present all-electron quantum Monte Carlo simulations on the anionic, neutral, and cationic boron clusters BQn with up to 13 atoms (Q = -1, 0, +1 and n ≤ 13). Accurate total energies of these clusters are obtained and an excellent agreement is reached with available experimental results for adiabatic and vertical detachment energies. We also perform very accurate Hartree-Fock calculations in the complete-basis-set limit where electron correlation is absent. In combination with the FN-DMC and HF-CBS results, we quantify the correlation effects and present the first attempt for a systematic investigation on the electron correlation effects in boron clusters. The obtained results show that, in general, electron correlation may contribute significantly to both the atomic and electronic structures of the boron clusters, manifested in the quantities such as the average binding energies of the clusters, atomic dissociation energies, detachment energies, and ionization potentials. For instance, the calculations indicate that the electron correlation maintains the bound state of cationic cluster B2+ and it also contributes 99% of the detachment energy of the anionic cluster B5-.

3.
Int Orthop ; 46(8): 1873-1880, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35608676

RESUMO

PURPOSE: The incidence of hip fractures is increasing exponentially due to an aging Brazilian population. Older people had significant comorbidities which increases the risk of post-operative mortality. Our purpose was to examine the association between pre-operative infections and comorbidities on the risk of post-operative in-hospital mortality after proximal femur fracture surgery's, beyond that, to evaluate the association between comorbidities and time to surgery. METHODS: This is a population-based cohort retrospective study, using medical records of all six year consecutive surgical procedures for correction of hip fracture in a tertiary teaching Hospital in Brazil. The exclusion criteria aimed to exclusively allocate patients who had their first hip fracture secondary to low-energy trauma. Multivariate logistical regression was performed and receiver operating characteristic (ROC) curve with area under curve (AUC) to evaluate the sensitivity and specificity of the model. p-value < 0.05 was considered significant. RESULTS: Final sample was composed by 856 consecutive patients with 81 years of median and 164 patients were excluded. The median length of hospital say was five days with - l mortality at 3.6%. Significant variables for increased mortality included the presence of pre-operative infection (odds ratio (OR): 3.9(1.12-8.54), chronic obstructive pulmonary disease (COPD) (OR: 3.83(1.36-10.82)), and systemic arterial hypertension (SAH) (OR: 4.1(1.18-14.25)). Development of pre-operative infection was associated with a delay to surgery (OR: 1.1 (1.08-1.13)). CONCLUSIONS: In older people with proximal femur fracture, the presence of pre-operative infection, COPD and SAH were the strongest risk factor for post-operative in-hospital mortality. Pre-operative infection was associated with statistically significant delay to surgery.


Assuntos
Fraturas do Quadril , Doença Pulmonar Obstrutiva Crônica , Idoso , Brasil/epidemiologia , Fraturas do Quadril/complicações , Fraturas do Quadril/cirurgia , Mortalidade Hospitalar , Humanos , Complicações Pós-Operatórias/epidemiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária
4.
Int Endod J ; 53(2): 265-275, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31519039

RESUMO

AIM: To evaluate the influence of ultraconservative endodontic cavities (UEC) on canal shaping and filling ability, cleaning of the pulp chamber, time required to perform root canal treatment and fracture resistance of 2-rooted maxillary premolars in comparison with traditional endodontic access cavities (TEC) in extracted teeth placed in a phantom head to simulate clinical conditions. METHODOLOGY: Twenty extracted intact 2-rooted maxillary premolars were scanned in a micro-computed tomographic device, matched based on similar anatomical features of the canals and assigned to UEC or TEC groups (n = 10). Then, teeth were mounted on a mannequin head and their pulp chamber accessed. After canal preparation, filling and cavity restoration, the time required to perform root canal treatment was recorded and the specimens were loaded to fracture in a universal testing machine. The maximum load at fracture was recorded. The sample was scanned after root canal instrumentation, filling and restoration procedures. Untouched canal areas, accumulation of hard-tissue debris (AHTD), voids in root fillings and cleaning of the pulp chamber were analysed. Data were analysed statistically using Shapiro-Wilk and Student's t-tests with a significance level of 5%. RESULTS: The percentage of untouched canal area did not differ significantly between UEC and TEC groups (P > 0.05). However, UECs were associated with a greater percentage of AHTD after canal preparation (P < 0.05). No differences were observed in terms of voids in root fillings between the groups (P > 0.05). Nonetheless, UEC had a greater percentage of root filling remnants in the pulp chamber after cleaning procedures (P < 0.05). The time required to perform root canal treatment was significantly longer in the UEC group (P < 0.05). There was no difference regarding the mean load at fracture between the groups (P > 0.05). Unrestorable fractures were observed in all specimens of both groups. CONCLUSIONS: There was no true benefit associated with ultraconservative endodontic cavities. UEC resulted in more AHTD remaining inside the root canals. UEC did not influence the quality of root fillings; however, UEC made the cleaning procedure of the pulp chamber more difficult, thus increasing the total time required to perform root canal treatment. Moreover, UEC were not associated with an increase in fracture resistance of root filled 2-rooted maxillary premolars.


Assuntos
Cavidade Pulpar , Materiais Restauradores do Canal Radicular , Dente Pré-Molar , Humanos , Preparo de Canal Radicular , Tratamento do Canal Radicular
5.
Reprod Fertil Dev ; 31(10): 1539-1544, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31270008

RESUMO

The aim of this study was to evaluate whether paternal exposure to bupropion hydrochloride (BUP), an inhibitor of dopamine and noradrenaline reuptake, would affect the postnatal development of offspring. Male mice were divided into a BUP-treated (40mgkg-1day-1 by gavage, 45 days) or control (saline by gavage, 45 days) group (n=20 in each group). From Day 35 to Day 45 of treatment, males were allowed to mate with drug-naïve female mice. Postnatal development of the offspring (both sexes) was evaluated from Postnatal day (PND) 1 to PND60. Physical development parameters (weight gain, body length, incisor eruption, pinna detachment), anogenital distance, vaginal opening, reflexes (palmar grasp, surface righting, negative geotaxis and adult gait) and some behavioural parameters (locomotor activity and anxiety-like behaviour) were altered in the offspring of BUP-treated males. The results demonstrate that paternal exposure to BUP induces long-lasting changes in the postnatal development of the offspring.


Assuntos
Bupropiona/toxicidade , Crescimento e Desenvolvimento/efeitos dos fármacos , Exposição Paterna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Comportamento Animal/efeitos dos fármacos , Feminino , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reflexo/efeitos dos fármacos , Reflexo/fisiologia
6.
Dermatol Online J ; 25(7)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31450284

RESUMO

Undifferentiated pleomorphic sarcoma is a common soft tissue sarcoma. Unfortunately, any attempt to describe the line of differentiation fails. It represents a final common pathway in tumors that undergoes progression towards dedifferentiation. We report a man with an undifferentiated pleomorphic sarcoma presenting as an exophytic pedunculated tumor of the left scapula. Histopathology analysis revealed spindle-shaped cells with great pleomorphism and numerous mitoses. Immunohistochemistry showed diffuse expression of vimentin. Wide local excision was performed after an oncology consultation. After two-years of follow-up, the patient has shown no evidence of recurrence or metastases.


Assuntos
Lipossarcoma/patologia , Neoplasias Cutâneas/patologia , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Humanos , Masculino , Escápula
7.
J Chem Phys ; 149(21): 214303, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30525724

RESUMO

The valence electron binding energies and the aromaticity of neutral and charged small boron clusters with three and four atoms are investigated using a combination of the fixed-node diffusion quantum Monte Carlo (FN-DMC) method, the density functional theory, and the Hartree-Fock approximation. The obtained electron binding energies such as the adiabatic detachment energy, vertical detachment energy, adiabatic ionization potential, and the vertical ionization potential are in excellent agreement with available experimental measurements. Their decomposition into three physical components such as the electrostatic potential and exchange interaction, the relaxation energy, and the electronic correlation effects has allowed us to determine that the neutral boron clusters are stabilized by the electrostatic and exchange interactions, while the anionic ones are stabilized by the relaxation and correlation effects. The aromaticity is studied based on electronic structure principles descriptor and on the resonance energy. The FN-DMC results from the electronic structure principles of the energy, hardness, and eletrophilicity have supported the aromaticity of B 3 - , B 4 - , and B4 and partially supported the aromaticity of the clusters B3, B 3 + , and B 4 + . The obtained values for the resonance energy of the clusters B 3 - , B3, B 3 + , B4, B 4 + , and B 4 - are 55.1(7), 54.2(8), 33.9(7), 84(1), 67(1), and 58(1) kcal/mol, respectively. Therefore, the order of decreasing stability of the trimer is B 3 - > B 3 > B 3 + , while for the tetramer it is B 4 > B 4 + > B 4 - , which is in agreement with the results from the molecular orbital analysis.

8.
Int Endod J ; 51(5): 556-563, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28470953

RESUMO

AIM: To report the main differences seen by direct visual inspection between original and counterfeit Reciproc instruments, together with an evaluation of instrument bending resistance, cyclic fatigue, surface finish, Vickers microhardness and chemical composition. METHODOLOGY: The visual aspects of original Reciproc R25 (VDW, Munich, Germany) and counterfeit Reciproc R25 instruments (claimed to be original, supposedly with dimensions similar to those of Reciproc R25 files, bought at www.mercadolivre.com.br) were evaluated under direct observation, stereomicroscopy and scanning electron microscope. The flexibility of original and counterfeit Reciproc R25 was determined via 45° bending tests according to the ISO 3630-1 specification. Instruments were also subjected to cyclic fatigue resistance, measuring the time to fracture in an artificial stainless steel canal with a 60° angle and 5-mm radius of curvature. The fracture surfaces of all fragments were examined under a scanning electron microscope. Roughness of the instruments was quantified using a profilometer, and the microhardness test was carried out using a Vickers hardness tester. Energy-dispersive X-ray microanalysis (EDX) was also carried out. Results were analysed statistically using the Student's t-test at a significance level of P < 0.05. RESULTS: Although the packaging of the original and counterfeit instruments was similar, a number of differences were observed such as ISO colour coding, measurement marks, stopper and morphologic characteristics. Original Reciproc instruments had significantly longer cyclic fatigue life and significantly lower bending resistance than counterfeit Reciproc instruments (P < 0.05), as well as significantly lower microhardness and roughness (P < 0.05). EDX results revealed differences in the chemical composition of the instruments (P < 0.05), indicating that the instruments were manufactured with different raw material. CONCLUSION: Original Reciproc files outperformed counterfeit instruments in all tests. It is thus important that identification strategies for these counterfeit instruments be developed, thereby preventing their inadvertent use.


Assuntos
Tratamento do Canal Radicular/instrumentação , Elasticidade , Falha de Equipamento , Fraude , Dureza , Humanos , Fenômenos Mecânicos , Microscopia Eletrônica de Varredura , Preparo de Canal Radicular/instrumentação
9.
J Adhes Dent ; 20(4): 335-340, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30206576

RESUMO

PURPOSE: To analyze the effect of a warm-air stream for solvent evaporation on the temperature rise in the pulp chamber during dentin hybridization. MATERIALS AND METHODS: Dentin disks with thicknesses of 0.5, 1.0 and 1.5 mm were obtained from extracted human molars. A model tooth was set up with the dentin disks between a molar with an exposed pulp chamber and a crown with an occlusal preparation. A K-type thermocouple connected to a digital thermometer was placed in the molar root until it entered the pulp chamber and made contact with the dentin disks. After 10 s of adhesive application, solvent evaporation was performed for 10, 20, 30, and 40 s and the increase in temperature was monitored for 200 s after the warm-air stream began. RESULTS: The temperature increase was significantly influenced by the thickness of the dentin disks (0.5 mm = 1.0 mm > 1.5 mm). With respect to the duration of the warm-air stream, the temperature increase was as follows: 10 s < 20 s < 30 s < 40 s (p < 0.05). The highest temperature was found after 40 s with dentin disks that were 0.5 mm (16.6°C) and 1.0 mm (15.8°C) thick, whereas the lowest temperature increase occurred after 10 s with a dentin disk that was 1.5 mm thick (4.1°C) (p < 0.05). CONCLUSION: The temperature in the pulp chamber was strongly influenced by the dentin thickness and the duration of the warm-air stream. Thinner dentin and a longer duration of the warm-air stream both lead to a greater temperature increase in the pulp chamber.


Assuntos
Adesivos Dentinários , Dentina , Cavidade Pulpar , Humanos , Solventes , Temperatura
10.
Ecotoxicol Environ Saf ; 145: 630-639, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28806565

RESUMO

In the present study, the possible associations between selected persistent organic pollutants (POPs) and biological factors were assessed in different tissues of two Antarctic notothenioid fish: Notothenia rossii (NOR) and Trematomus newnesi (TRN) collected at Potter Cove, King George Island/Isla 25 de Mayo, South Shetland Islands. Specifically, association patterns between biological factors (body size, lipid content, body condition) and POP concentrations (polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and metabolites, polybrominated diphenyl ethers (PBDEs), and hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), chlordanes (CHLs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs)), were explored by using two approaches: multivariate analyses (principal component analysis: PCA) and intraspecific correlations. Integrating results suggest that biological factors such as size, KI and tissue type seemed to be associated to selective accumulation of POPs for immature specimens of N. rossii, and KI and tissue type for mature specimens of T. newnesi. Each particular factor should be considered when choosing N. rossii or T. newnesi as sentinels for POPs pollution in Antarctic marine environments. Further, both nototheniids showed a selective accumulation pattern in their gonads of penta-chlorinated biphenyls (penta-CBs; 55.5 and 29ngg-1 lw for N. rossii and T. newnesi, respectively) and organochlorine pesticides such as DDTs (199 and 13.3ngg-1 lw, for N. rossii and T. newnesi respectively), and of polybrominated diphenyl ethers (PBDEs) in gills (97.2 and 22.1 for ngg-1 lw, for N. rossii and T. newnesi, respectively), highlighting the importance of these tissues in monitoring studies of pollution in fish. The current study expands the knowledge concerning the biological factors to be investigated when specific pollutants are monitored and supports the importance of tissue type for the selective accumulation of POPs in Antarctic fish. Additionally, a contribution to the scarce data on concentration of MeO-PBDEs in Antarctic marine organisms, particularly in the highly diverse perciform suborder Notothenioidei is provided.


Assuntos
Tamanho Corporal , Monitoramento Ambiental/métodos , Hidrocarbonetos Halogenados/metabolismo , Tamanho do Órgão , Perciformes/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Regiões Antárticas , Tamanho Corporal/fisiologia , Brânquias/metabolismo , Gônadas/metabolismo , Hidrocarbonetos Halogenados/análise , Ilhas , Tamanho do Órgão/fisiologia , Especificidade da Espécie , Poluentes Químicos da Água/análise
11.
Dermatol Online J ; 23(4)2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28541881

RESUMO

Paget disease of the breast is an uncommon tumor of the nipple-areola complex that usually presents as an erythematous and erosive lesion. We report the case of a 61-year-old man that presented with a three-year history of an erythematous lesion of the right areola, first treated with topical corticosteroids without benefit. He was then referred to our dermatology department and the clinical suspicion of Paget disease was considered. The diagnosis was later confirmed by biopsy. This case report highlights the importance of clinical recognition of this entity along with other diseases that mimic these skin changes in order to allow earlier diagnosis and proper follow-up.


Assuntos
Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/patologia , Doença de Paget Mamária/diagnóstico , Doença de Paget Mamária/patologia , Biópsia , Proteínas de Transporte/metabolismo , Glicoproteínas/metabolismo , Humanos , Queratina-7/metabolismo , Masculino , Proteínas de Membrana Transportadoras , Pessoa de Meia-Idade , Mamilos
12.
Scand J Rheumatol ; 45(5): 363-70, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26815734

RESUMO

OBJECTIVES: To assess the effectiveness of foot orthoses with regard to pain, function, quality of life, and global perceived effect in patients with rheumatoid arthritis (RA). METHOD: A double-blind randomized controlled trial (RCT) was carried out. Eighty women with RA were randomly assigned to an experimental group (EG) or a control group (CG). The EG used an insole with metatarsal and medial arch supports and the CG used a flat insole for 6 months. Evaluations performed at baseline and after 45, 90, and 180 days by a blinded assessor were: foot pain while walking and at rest, function, quality of life, and global perceived effect with treatment. RESULTS: The groups were homogeneous for all parameters at baseline. A statistically significant improvement (p < 0.001) was found in the EG regarding pain while walking (mean difference: -2.2 for the right foot and -2.1 for the left foot) and at rest (mean difference: -0.3 for the right foot and -0.5 for the left foot) in comparison to CG. There were no differences in any other observed measures. The time of insole use correlated with foot pain and function in the EG. CONCLUSIONS: Foot orthoses with metatarsal and medial arch supports decreases pain during walking and at rest in both feet in patients with RA. Time of insole use correlated with improvements in pain and function.


Assuntos
Artrite Reumatoide/reabilitação , Órtoses do Pé , Dor/reabilitação , Satisfação do Paciente , Qualidade de Vida , Adulto , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Caminhada
13.
Dis Aquat Organ ; 121(1): 49-57, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27596859

RESUMO

Monthly samples of smelt Osmerus eperlanus (Linnaeus, 1758) were collected from July 1985 to May 1986, in the river Elbe (Germany), and examined for infections with microsporidians. Two microsporidians were found: Glugea hertwigi Weissenberg, 1911, infecting the digestive tract and Pleistophora ladogenis Voronin, 1978, infecting the skeletal musculature. G. hertwigi infection led to the formation of xenomas, whereas P. ladogensis was characterized by diffuse infections, with the production of macroscopic visible thread-like or oval-shaped infection foci. Development of G. hertwigi in the host cells showed characteristics typical of the genus Glugea. The ultrastructural development of P. ladogensis showed features typical of the genus Pleistophora, without evidence of the production of 2 types of spores. Host reaction consisted of inflammatory tissue surrounding some of the infection foci as well as phagocytosis of spores. G. hertwigi was only found in juvenile smelt (<10 cm in length), whereas P. ladogensis infected smelts from 6 to 26 cm in length. Prevalence increased with fish length to a maximum value of 9.6%. Seasonal fluctuations in prevalence of infection were also found, with the lowest value in the winter months (2.5% in January 1986) and the highest in summer (11.8% in July 1985). The differences in prevalence of infection with fish length and date of sampling were significant. Additionally, samples of smelt caught in April 1986 from the rivers Eider and Ems revealed infections with P. ladogensis in the first river system only.


Assuntos
Doenças dos Peixes/parasitologia , Glugea/isolamento & purificação , Microsporidiose/veterinária , Osmeriformes , Pleistophora/isolamento & purificação , Animais , Doenças dos Peixes/epidemiologia , Alemanha/epidemiologia , Lansoprazol , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Mar do Norte/epidemiologia
14.
Genet Mol Res ; 15(1)2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26909904

RESUMO

The objective of this study was to assess the efficiency of a modification of the simulated individual best linear unbiased prediction (BLUPIS) procedure, which is used for the approximation of classic individuals (BLUPI) for selection between and within sugarcane families. A total of 110 full-sib families were employed in an experiment initiated in 2007 using a randomized block design with five replicates. The variable tons of stalks per hectare was measured from a plot containing 20 plants. The modified BLUPIS (BLUPISM) procedure showed a 0.98 correlation with BLUPI, thus demonstrating great efficiency in selecting individuals in sugarcane families during the initial phase of genetic breeding programs.


Assuntos
Cruzamento , Modelos Genéticos , Saccharum/genética , Seleção Genética
15.
Plant Dis ; 99(9): 1216-1226, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30695930

RESUMO

Experiments were conducted in Mato Grosso, Brazil, from 2009 to 2011 to evaluate the effects of planting date (October, November, December, and January) on soybean rust (SBR) and leaf area index (LAI) in SBR-susceptible soybean cultivars of different maturity groups (early-maturing, midseason, and late-maturing). Mean relative area under the LAI progress curve (RAULAIPC) was significantly higher (P < 0.05) for the late-maturing than early-maturing and midseason cultivars. The October planting date had significantly higher (P < 0.05) mean RAULAIPC than the December and January planting dates. Mean relative area under the SBR progress curve was significantly lower (P < 0.05) for the late-maturing than the midseason and early-maturing cultivars, and significantly higher (P < 0.05) for the December and January than the October and November planting dates. Based on the logistic population growth model, SBR severity increased over time at a significantly higher mean rate for the early-maturing than the midseason and late-maturing cultivars. It took longer for SBR to reach a certain severity level for the late-maturing cultivar planted in January than the early-maturing cultivar planted in October. This implies that fungicides would need to be applied early to the early-maturing cultivar planted in October to minimize yield loss.

16.
New Phytol ; 203(2): 401-413, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24725318

RESUMO

A basic understanding of nutrition effects on the mechanisms involved in tree response to drought is essential under a future drier climate. A large-scale throughfall exclusion experiment was set up in Brazil to gain an insight into the effects of potassium (K) and sodium (Na) nutrition on tree structural and physiological adjustments to water deficit. Regardless of the water supply, K and Na supply greatly increased growth and leaf area index (LAI) of Eucalyptus grandis trees over the first 3 yr after planting. Excluding 37% of throughfall reduced above-ground biomass accumulation in the third year after planting for K- supplied trees only. E. grandis trees were scarcely sensitive to drought as a result of the utilization of water stored in deep soil layers after clear-cutting the previous plantation. Trees coped with water restriction through stomatal closure (isohydrodynamic behavior), osmotic adjustment and decrease in LAI. Additionally, droughted trees showed higher phloem sap sugar concentrations. K and Na supply increased maximum stomatal conductance, and the high water requirements of fertilized trees increased water stress during dry periods. Fertilization regimes should be revisited in a future drier climate in order to find the right balance between improving tree growth and limiting water shortage.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Eucalyptus/fisiologia , Potássio/farmacologia , Sódio/farmacologia , Biomassa , Brasil , Secas , Eucalyptus/efeitos dos fármacos , Eucalyptus/crescimento & desenvolvimento , Floema/química , Floema/metabolismo , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Estações do Ano , Solo
17.
Genet Mol Res ; 13(1): 1650-60, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24535897

RESUMO

We evaluated the genetic diversity of 77 clones of sugarcane used in crosses made by the Brazilian interuniversity network for the development of the sugar/energy sector (RIDESA) breeding program. Characterization of the genotypes was carried out at the ratoon stage, based on eight morphological traits and seven agronomic traits. Diversity analysis was carried out beginning with the Ward-Modified Location Model. The ideal number of groups was three. Groups 1, 2, and 3 were composed of 37, 21, and 19 accessions, respectively. Group 1 was formed entirely of commercial varieties (hybrids of advanced generations) and elite clones, with the exception of the old varieties 'Caiana Fita' and 'Cana Blanca' (hybrids of Saccharum officinarum). In general, group 2 had more divergent accessions regarding origin, including L60-14, NG57-6, TUC77-42, IN84-105 (hybrid of S. officinarum), and 28NG289 (species of S. robustum). Group 3 was formed entirely of commercial varieties and elite clones from the RIDESA program, with the exception of genotypes Co285 (India), Q124 (Australia) and VAT90-212 (unknown origin). The analysis based on the Ward-Modified Location Model procedure resulted in an adequate and clearly discriminating grouping of sugarcane accessions, allowing the use of all the available information about the genotypes, in a mix of continuous and categorical variables.


Assuntos
Cruzamento , Variação Genética , Saccharum/genética , Brasil , Análise por Conglomerados , Genótipo , Fenótipo , Especificidade da Espécie
18.
Plant Dis ; 98(1): 84-89, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30708583

RESUMO

This study aimed to determine whether foliar sprays of potassium silicate (KSi), sodium molybdate (NaMo), or a combination of both (KSi + NaMo), with or without the fungicide azoxystrobin (Azox), could reduce anthracnose symptoms and, consequently increase yield. Two two-by-four factorial experiments, consisting of untreated or fungicide treated, as well as sprays of KSi, NaMo, KSi + NaMo, and no spray (control), were arranged in a randomized block design with three replications. Treatments were as follows: treatment 1, KSi spray; treatment 2, NaMo spray; treatment 3, KSi + NaMo spray; treatment 4, Azox spray; treatment 5, Azox + KSi spray; treatment 6, Azox + NaMo spray, treatment 7, Azox + KSi + NaMo spray; and treatment 8, control (no KSi, NaMo, or Azox). The KSi, NaMo, and Azox treatments were sprayed at the rates of 35 g/liter, 90 g/ha, and 120 g a.i./ha, respectively. The KSi was applied at 20, 27, 40, and 55 days after sowing (das). The NaMo was sprayed only at 27 das whereas the fungicide was sprayed at 27, 40, and 55 das. Plants were inoculated with Colletotrichum lindemuthianum at 23 das. Azox reduced the mean area under disease progress curve (AUDPC) by 63% and mean yield was increased by 150%. Similarly, the mean AUDPC was reduced by 29, 14, and 41% with KSi, NaMo, and KSi + NaMo sprays, respectively, while mean yield increased by 13, 20, and 47%, with KSi, NaMo, or KSi + NaMo sprays, respectively. The variables leaf area index (LAI), leaf area index duration (LAD), healthy leaf area duration (HAD), and radiation intercepted (RI) were not affected by KSi spray. The values for the variables LAI, healthy leaf area index (HLAI), LAD, HAD, RI, intercepted radiation of the healthy leaf area, and healthy leaf area absorption were significantly increased as a result of NaMo spray. The results of the present study support the novel possibility of using a foliar spray of KSi in association with NaMo to decrease anthracnose symptoms in bean plants and, consequently, achieve greater yield.

19.
Polymers (Basel) ; 16(17)2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39274034

RESUMO

The objective of this study was to evaluate the effect of incorporating different concentrations of graphene oxide (GO) nanoparticles on the mechanical properties of a resin-modified glass ionomer cement (RMGIC). A commercial RMGIC (Resiglass R, Biodinâmica) was modified by incorporating 0.1% and 0.5% (by weight) of GO into the powder's material. An unmodified RMGIC was used as a control group. Powder samples were characterized using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Specimens were fabricated and subjected to flexural strength (n = 15), modulus of elasticity (n = 15), Vicker's microhardness (n = 10), and surface roughness tests (n = 10). Data were analyzed using one-way ANOVA and Tukey's post hoc test (α = 5%). Experimental groups' powder demonstrated a homogeneous dispersion of GO. No statistically significant difference was observed in flexural strength (p = 0.067) and modulus of elasticity (p = 0.143) tests. The groups containing 0.1% and 0.5% GO showed significantly higher microhardness and lower surface roughness values (p < 0.001) compared to the control group. The incorporation of GO nanoparticles at concentrations of 0.1% and 0.5% improved the microhardness and surface roughness without negatively affecting the flexural strength and modulus of elasticity of an RMGIC.

20.
Braz J Anesthesiol ; 74(4): 844500, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38554793

RESUMO

BACKGROUND: There is no consensus on the most effective strategy for Postoperative Pulmonary Complication (PPC) reduction. This study hypothesized that a Goal-Directed Fluid Therapy (GDFT) protocol of infusion of predetermined boluses reduces the occurrence of PPC in patients undergoing elective open abdominal surgeries when compared with Standard of Care (SOC) strategy. METHODS: Randomized, prospective, controlled study, conducted from May 2012 to December 2014, with ASA I, II or III patients undergoing open abdominal surgeries, lasting at least 120 min, under general anesthesia, randomized into the SOC and the GDFT group. In the SOC, fluid administration was according to the anesthesiologist's discretion. In the GDFT, the intervention protocol, based on bolus infusion according to blood pressure and delta pulse pressure, was applied. Patients were postoperatively evaluated by an anesthesiologist blinded to the group allocation regarding PPC incidence, mortality, and Length of Hospital Stay (LOHS). RESULTS: Forty-two patients in the SOC group and 43 in the GDFT group. Nineteen patients (45%) in the SOC and 6 in the GDFT (14%) had at least one PPC (p = 0.003). There was no difference in mortality or LOHS between the groups. Among the patients with PPC, four died (25%), compared to two deaths in patients without PPC (3%) (p = 0.001). The LOHS had a median of 14.5 days in the group with PPC and 9 days in the group without PPC (p = 0.001). CONCLUSION: The GDFT protocol resulted in a lower rate of PPC; however, the LOHS and mortality did not reduce.


Assuntos
Abdome , Hidratação , Pneumopatias , Complicações Pós-Operatórias , Humanos , Estudos Prospectivos , Masculino , Feminino , Hidratação/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Pessoa de Meia-Idade , Abdome/cirurgia , Pneumopatias/etiologia , Idoso , Tempo de Internação , Adulto , Anestesia Geral/métodos
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