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1.
Acta Orthop Belg ; 89(1): 45-50, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37294984

ABSTRACT

The objective of the present study is to perform a systematic review with meta-analysis of the literature on treatment of developmental dysplasia of the hip (DDH) in patients over eight years of age to provide better understanding of therapeutic strategies and results. Authors carried out a systematic review and metanalysis of the literature on DDH treated in patients aged eight years of age or older. A literature search was carefully performed from June 2019 to June 2020. The articles had to report one stage reconstructive surgical treatment of DDH for patients eight years or older, presenting clinical and radiographic evaluation according to the Tonnis and Severin, and McKay systems. Meta-analysis was carried out using the software metanalyst to perform the pooled effect size Nine studies met the inclusion criteria. They assessed a total of 234 patients and 266 hips. Female patients accounted for 75.7% (eight unknown) and the follow-up ranged from 1 to 17.4 years. The majority of the procedures included an acetabular surgery (93.9%) while femoral shortening was performed in 78%. Acceptable outcomes were found in between 67% (Mckay system) and 91% (Severin system) of the cases. Femoral varus and derrotation shortening associated with redirectional osteotomy of the acetabulum (for those with closed triradiate cartilage) or acetabular redirection/reshaping were the most prevalent combined procedures; this strategy can lead to 60% of acceptable clinical results and 90% of radiographically acceptable results. Therefore, our findings give credence to the recommendation for the treatment of DDH in patients over eight years old.


Subject(s)
Developmental Dysplasia of the Hip , Hip Dislocation, Congenital , Humans , Female , Child , Hip Dislocation, Congenital/diagnostic imaging , Hip Dislocation, Congenital/surgery , Developmental Dysplasia of the Hip/diagnostic imaging , Developmental Dysplasia of the Hip/surgery , Developmental Dysplasia of the Hip/complications , Treatment Outcome , Retrospective Studies , Acetabulum/diagnostic imaging , Acetabulum/surgery
2.
Sci Rep ; 12(1): 4983, 2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35322091

ABSTRACT

The robot-environment-task triad provides many opportunities to revisit physical problems with fresh eyes. Hence, we develop a simple experiment to observe chaos in classical billiards with a macroscopic 3.38-m long setup. Using a digital video camera, one records the dynamic time evolution of the interaction between a robot and Bunimovich stadium billiards with specular reflection. From the experimental time series, we calculate the Lyapunov exponent [Formula: see text] as a function of a geometric parameter. The results are in concordance with theoretical predictions. In addition, we determine the Poincaré surface of section from the experimental data and check its sensitivity to the initial conditions as a function of time.

3.
Phys Rev E ; 105(1-1): 014213, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35193323

ABSTRACT

The well-known Vicsek model describes the dynamics of a flock of self-propelled particles (SPPs). Surprisingly, there is no direct measure of the chaotic behavior of such systems. Here we discuss the dynamical phase transition present in Vicsek systems in light of the largest Lyapunov exponent (LLE), which is numerically computed by following the dynamical evolution in tangent space for up to two million SPPs. As discontinuities in the neighbor weighting factor hinder the computations, we propose a smooth form of the Vicsek model. We find a chaotic regime for the collective behavior of the SPPs based on the LLE. The dependence of LLE with the applied noise, used as a control parameter, changes sensibly in the vicinity of the well-known transition points of the Vicsek model.

4.
Vet Pathol ; 50(4): 582-4, 2013 Jul.
Article in English | MEDLINE | ID: mdl-22961885

ABSTRACT

The stomachs of 100 free-ranging black caimans (Melanosuchus niger Spix, 1825) from the Mamirauá Sustainable Development Reserve, Amazonas state, Brazil, were examined for parasitism and pathologic lesions. All animals were harvested for human consumption. Ascaridoid nematodes were found in 67 caimans and were identified as Brevimulticaecum sp. These parasites were associated with focally extensive, chronic gastric ulcers and formation of localized intramural granulomas containing nematodes. All caiman were in good nutritional condition, which suggests that effects of gastric nematodiasis on the crocodilian hosts were minimal at the time of slaughter.


Subject(s)
Alligators and Crocodiles/parasitology , Ascaridida Infections/veterinary , Ascaridoidea/isolation & purification , Granuloma/veterinary , Stomach Ulcer/veterinary , Animals , Ascaridida Infections/pathology , Brazil , Chronic Disease , Granuloma/parasitology , Granuloma/pathology , Humans , Male , Stomach/parasitology , Stomach/pathology , Stomach Ulcer/parasitology , Stomach Ulcer/pathology
6.
Braz. j. med. biol. res ; 45(2): 118-124, Feb. 2012. ilus, tab
Article in English | LILACS | ID: lil-614572

ABSTRACT

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1 percent, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78 percent. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Subject(s)
Animals , Female , Albizzia/chemistry , Coleoptera/drug effects , Seed Storage Proteins/toxicity , Seeds/chemistry , Larva/drug effects
7.
Braz J Med Biol Res ; 45(2): 118-24, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22267002

ABSTRACT

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Subject(s)
Albizzia/chemistry , Coleoptera/drug effects , Seed Storage Proteins/toxicity , Seeds/chemistry , Animals , Female , Larva/drug effects
8.
Arq. bras. med. vet. zootec ; 63(1): 74-80, Feb. 2011. tab
Article in Portuguese | LILACS | ID: lil-582327

ABSTRACT

Avaliou-se a viabilidade do transporte de oócitos em meio quimicamente definido, e analisou-se a necessidade da adição ou não de hormônios neste meio. Os oócitos do grupo-controle (0h) foram maturados por 24h em estufa de CO2, e os dos grupos experimentais foram transportados em incubadora portátil. No experimento I, as taxas de clivagem foram similares (P>0,05) para os grupos 0h (59,7 por cento), 3h (53,5 por cento) e 9h (48,8 por cento), e houve redução nos grupos 6h (46,1 por cento) e 12h (43,8 por cento). Essas taxas foram semelhantes entre os grupos 3h, 6h, 9h e 12h. A produção de blastocistos não foi diferente (P>0,05) para os grupos 0h (38,0 por cento), 3h (32,3 por cento), 6h (27,3 por cento) e 9h (24,8 por cento), e houve redução no grupo 12h (18,9 por cento). Essas taxas foram semelhantes entre os grupos 6h, 9h e 12h. No experimento II, não houve diferença (P>0,05) entre as taxas de clivagem para os grupos 0h (71,4 por cento), 3h (70,3 por cento), 6h (56,0 por cento) com hormônios, e os grupos 3h (64,8 por cento) e 6h (54,1 por cento) sem hormônios. A produção de blastocistos foi similar (P>0,05) para os grupos 0h (46,1 por cento), 3h com hormônios (45,8 por cento) e 3h sem hormônios (41,1 por cento), porém houve redução nos grupos 6h com hormônios (35,5 por cento) e 6h sem hormônios (33,5 por cento). Essas taxas foram semelhantes entre os grupos 3h sem hormônios e 6h com e sem hormônios. Estes resultados indicam que é possível otransporte de oócitos bovinos por um período de até nove horas, e que a adição de hormônios neste meio não influencia os índices de clivagem e de blastocistos.


The viability of the transport of the bovine oocytes was evaluated in chemically defined medium and the need for the addition or not of hormones in this medium was analyzed. The oocytes in the control group (0h) were matured for 24h in CO2 incubator, and in experimental groups they were transported in portable incubator. In experiment I, the cleavage rates were similar (P>0.05) to the groups 0h (59.7 percent), 3h (53.5 percent), and 9h (48.8 percent), but they decreased in groups 6h (46.1 percent) and 12h (43.8 percent), however, these rates were similar among the groups 3h, 6h, 9h, and 12h. The production of blastocysts was not different (P>0.05) for groups 0h (38.0 percent), 3h (32.3 percent), 6h (27.3 percent), and 9h (24.8 percent), but there was a reduction in the 12h group (18.9 percent). These rates were similar among the groups 6h, 9h and 12h. In experiment II, no significant difference (P>0.05) was observed among the rates of cleavage for the groups 0h (71.4 percent), 3h with (70.3 percent) and without hormones (64.8 percent), and 6h with (56.0 percent) and without hormones (54.1 percent). The production of blastocysts was similar (P>0.05) for groups 0h (46.1 percent) and 3h with (45.8 percent) and without hormones (41.1 percent), but decreased in groups 6h with (35.5 percent) and without hormones (33.5 percent). These rates were similar among the groups 3h without, 6h with and without hormones. These results indicate the possibility of the transport of bovine oocytes up to 9h, and the addition of hormones in this medium does not influence the rates of cleavage and blastocysts.


Subject(s)
Animals , Cattle/classification , Oocytes/cytology , Atmosphere/analysis , Embryology/methods
9.
J Environ Manage ; 91(3): 685-9, 2010.
Article in English | MEDLINE | ID: mdl-19906480

ABSTRACT

The present study focuses on the recycling of gneiss rock waste generated by the ornamental rock industry for manufacturing vitrified floor tile products. The gneiss rock waste came from a rock-cutting plant located in Santo Antônio de Pádua-RJ, Brazil. Initially the waste sample was characterized for chemical composition, X-ray diffraction, particle size, morphology, and pollution potential. Floor tiles containing up to 47.5wt.% waste were prepared. The tiles were tested to determine their physical-mechanical properties (linear shrinkage, water absorption, apparent density, and flexural strength). Microstructural evolution was carried out by scanning electron microscopy. The results indicate that the gneiss rock waste could be used for vitrified floor tile production, resulting in a new possibility for recycling this waste and conserving natural resources.


Subject(s)
Conservation of Natural Resources/methods , Construction Materials , Geologic Sediments , Industrial Waste , Manufactured Materials , Refuse Disposal/methods , Brazil , Floors and Floorcoverings , Geologic Sediments/chemistry
10.
J Epidemiol Community Health ; 62(10): 899-904, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18413434

ABSTRACT

BACKGROUND: The aim of this study was to examine the effect of household income on unintentional injury mortality in children and to model the potential impact of eradicating income poverty as an injury prevention strategy. METHODS: A national retrospective cohort study linking census to mortality records carried out in New Zealand during a 3-year period following the 1991 census and including children aged 0-14 years on census night. The main outcome measures are odds ratios (ORs) for unintentional injury death by equivalised household income category and proportional reductions (population-attributable risk) in unintentional injury mortality from modelled scenarios of nil poverty. RESULTS: One-third of children lived in households earning less than 60% of the national median household income. Age-adjusted odds of death from unintentional injury were higher for children from any income category compared with the highest, and were most elevated for children from households earning less than 40% of the national median income (OR 2.81, 95% CI 1.73 to 4.55). Adjusting for ethnicity, household education, family status and labour force status halved the effect size (OR 1.83, 1.02 to 3.28). Thirty per cent of injury mortality was attributable to low or middle household income using the highest income category as reference. Altering the income distribution to eradicate poverty, defined by a threshold of 50% or 60% of the national median income, reduced injury mortality in this model by a magnitude of 3.3% to 6.6%. CONCLUSIONS: Household income is related to a child's risk of death from unintentional injury independent of measured confounders. Most deaths attributable to low income occur among households that are not defined as "in poverty". The elimination of poverty may reduce childhood unintentional injury mortality by 3.3% to 6.6%.


Subject(s)
Models, Econometric , Poverty/statistics & numerical data , Wounds and Injuries/mortality , Adolescent , Child , Child, Preschool , Epidemiologic Methods , Female , Humans , Infant , Infant, Newborn , Male , New Zealand/epidemiology , Poverty/prevention & control , Socioeconomic Factors , Wounds and Injuries/prevention & control
11.
Lupus ; 17(2): 105-13, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18250133

ABSTRACT

To determine the frequency of carotid plaque and intima-media thickness (IMT) in patients with systemic lupus erythematosus (SLE) and their association with risk factors in a Brazilian university setting. Carotid plaque and IMT were identified and measured by ultrasonography. Traditional risk factors and lupus-related factors were analysed. One hundred and seventy-two patients (women = 96%, age = 38 +/- 11 years) were evaluated. The frequency of carotid plaque was 9.3%. The median (IR) IMT was 0.60 mm (0.54-0.71 mm). Age, family history (FH) of premature coronary disease, low-density cholesterol (LDL-c) >100 mg/dL, hypertriglyceridemia, diabetes, hypertension, smoking, postmenopause, number of risk factors, Framingham risk score, age at diagnosis, duration of lupus, mucocutaneous manifestations and duration of prednisone use were associated with plaque (P < 0.05), univariate analysis. Nephritis, immunosuppressive therapy, intravenous methylprednisolone and a higher average daily dose of prednisone were associated with the absence of plaque. Independent predictors of plaque were smoking (P = 0.004), LDL-c >100 mg/dL (P = 0.044), Framingham score (P = 0.006) and absence of immunosuppressive therapy (P = 0.032). There was an independent correlation between IMT and age (P < 0.001) and duration of prednisone use (P = 0.020). Subclinical atherosclerosis was associated with traditional risk and SLE-related factors, especially the absence of immunosuppressive therapy. The present study suggests that the levels of LDL-c should be kept under 100mg/dL in lupus.


Subject(s)
Atherosclerosis/diagnostic imaging , Atherosclerosis/etiology , Carotid Artery Diseases/diagnostic imaging , Carotid Artery Diseases/etiology , Lupus Erythematosus, Systemic/complications , Adult , Atherosclerosis/pathology , Brazil , Carotid Artery Diseases/pathology , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/pathology , Cholesterol, LDL/blood , Cross-Sectional Studies , Female , Humans , Immunosuppressive Agents/therapeutic use , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/drug therapy , Male , Methylprednisolone/therapeutic use , Middle Aged , Prednisone/therapeutic use , Risk Factors , Tunica Intima/diagnostic imaging , Tunica Intima/pathology , Tunica Media/diagnostic imaging , Tunica Media/pathology , Ultrasonography
12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 72(1 Pt 2): 016116, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16090045

ABSTRACT

Relying on the fractal character of the largest clusters at criticality, we employ a finite-size scaling analysis to obtain an accurate phase-diagram of the percolation transition in chains with bond concentration decaying as a power-law on the form 1/ r(1+sigma) . For the particular case of sigma=1, no percolation transition is observed to occur at a finite dilution, in contrast with the finite temperature Kosterlitz-Thouless transition exhibited in Ising and Potts chains with inverse square-law couplings. The fractal dimension of the critical percolation cluster is found to follow distinct dependencies on the decay exponent being numerically fitted by d(f) =0.35+4sigma/5 for 0

13.
Talanta ; 64(1): 190-5, 2004 Sep 08.
Article in English | MEDLINE | ID: mdl-18969587

ABSTRACT

The equilibrium constants and molar absorptivities for the fast formation of a 1:3 complex between cadmium(II) (Cd(II)) and dithizonate anion, in the presence of cationic and non-ionic surfactants, allowed a simple and fast spectrophotometric determination of total cadmium. Indeed, the molar absorptivities of the Cd(II)-dithizone (Dz) complex formed in the presence of the neutral Triton X-100 and cationic cetyltrimethylammonium bromide (CTAB) surfactants are almost twice the value observed in the standard method and the maxima of absorption are shifted by about 40nm when compared with the standard method. Clearly, the use of neutral and cationic surfactants promotes a higher value of the molar absorptivities of the complex, resulting in an increase in the sensitivity of the method. Application of the method to the desorption of Cd(II) ions from clays is illustrated.

14.
J Pept Res ; 56(5): 326-34, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11095186

ABSTRACT

Deamidation kinetics were measured for a model hexapeptide (L-Val-L-Tyr-L-Pro-L-Asn-Gly-L-Ala, 0.02 mg/mL) in aqueous solutions containing glycerol (0-50% w/w) and poly(vinyl pyrrolidone) (PVP, 0-20% w/w) at 37 degrees C and pH 10 to determine the effects of solution polarity and viscosity on reactivity. The observed pseudo-first order deamidation rate constants, k(obs), decreased markedly when the viscosity increased from 0.7 to 13 cp, but showed no significant change at viscosities >13 cp. Values of k(obs) also increased with increasing dielectric constant and decreasing refractive index. Molecular dynamics simulations indicated that the free energy associated with Asn side-chain motion is insensitive to changes in dielectric constant, suggesting that the observed dielectric constant dependence is instead related primarily to the height of the transition state energy barrier. An empirical model was proposed to describe the effects of the viscosity, refractive index and dielectric constant on k(obs). Analysis of the regression coefficients suggested that both permanent and induced dipoles of the medium affect the deamidation rate constant, but that solution viscosity is relatively unimportant in the range studied.


Subject(s)
Amides/metabolism , Oligopeptides/chemistry , Oligopeptides/metabolism , Solutions/chemistry , Solutions/metabolism , Computer Simulation , Glycerol/chemistry , Glycerol/metabolism , Kinetics , Povidone/chemistry , Povidone/metabolism , Refractometry , Regression Analysis , Static Electricity , Viscosity
15.
Int J Exp Pathol ; 78(6): 391-9, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9516871

ABSTRACT

Latent Trypanosoma cruzi infection may be reactivated in immunosuppressed individuals, with unusual clinical patterns, such as meningoencephalitis, pseudo neoplastic lesions in the central nervous system, and myocarditis with numerous parasites in the heart muscle. To investigate this problem 68 Swiss mice chronically infected with different strains of T. cruzi were treated with different combinations of immunosuppressive drugs (azathioprine, cyclosporine and betamethasone), in such a way as to imitate the situation during post transplantation treatment. Mortality varied from 6 to 25% in treated mice. There were no deaths in untreated controls. Normal mice have been submitted to the same schedules of immunosuppression as controls of treatment and no deaths were registered during treatment. Chronically infected mice showed significant elevation of total number of leukocytes and lymphocytes in comparison with intact controls; a significant decrease in blood leukocytes and lymphocytes occurred post-treatment in two of the treated experimental groups. Exacerbation of myocarditis and myositis and a high incidence of brain lesions, with focal necrosis, granulomatous lesions and glial proliferation even in the absence of parasites were present in immunosuppressed mice but not in infected controls. Although differing in some aspects from Chagas' disease in immunosuppressed humans, the murine model did show some features that resembled it, especially the peculiar pattern of central nervous system involvement.


Subject(s)
Chagas Disease/immunology , Disease Models, Animal , Immunosuppressive Agents/adverse effects , Animals , Antibodies, Helminth/blood , Azathioprine/adverse effects , Betamethasone/adverse effects , Brain/parasitology , Chronic Disease , Cyclosporine/adverse effects , Leukocyte Count , Lymphocyte Count , Mice , Mice, Inbred Strains , Recurrence , Transplantation
16.
Arq Bras Cardiol ; 59(2): 127-30, 1992 Aug.
Article in Portuguese | MEDLINE | ID: mdl-1341157

ABSTRACT

A 33-year-old female patient, with a 4-year history of hypertension plus a 3-year history of systemic lupus erythematosus, who had been taking high dosages of corticosteroids, has shown repetitive respiratory infections and congestive heart failure for the past 8 months. Angiocardiography confirmed the diagnosis of aortic insufficiency with aneurysmatic dilation of Valsalva's posterior sinus, ascending aorta of normal diameter and normal coronary arteries. Aortic dissection causing aortic insufficiency due to collapse of aortic leaflets was spotted during the surgery and was corrected by a bovine pericardial tube and suspension of aortic valve. The postoperative (PO) period was complicated by left-sided seizures followed by left hemiparesis and respiratory infection. She was discharged on the 25th PO day with mild left hemiparesis and in functional class I (NYHA), using medicines. We emphasize the need to consider the diagnosis of aortic dissection in patients with systemic lupus erythematosus and aortic insufficiency, specially in those who have a history of systemic arterial hypertension and long-term corticosteroid therapy.


Subject(s)
Aortic Aneurysm, Thoracic/etiology , Aortic Dissection/etiology , Lupus Erythematosus, Systemic/complications , Adult , Aortic Dissection/diagnosis , Aortic Dissection/surgery , Aortic Aneurysm, Thoracic/diagnosis , Aortic Aneurysm, Thoracic/surgery , Aortic Valve Insufficiency/diagnosis , Aortic Valve Insufficiency/etiology , Aortic Valve Insufficiency/surgery , Chronic Disease , Female , Humans , Hypertension/complications
20.
CAREC Surveillance Report ; 6(10): 1-3, Oct. 1980.
Article in En | Desastres -Disasters- | ID: des-4654
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