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1.
Reumatismo ; 75(1)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37154251

RESUMO

Systemic autoimmune myopathies (SAMs) are rare diseases that lead to muscle inflammation and may be associated with a variety of systemic manifestations. Although there is great heterogeneity in the spectrum of extra-muscular involvement in SAMs, interstitial lung disease (ILD) is the most frequent lung manifestation. SAM-related ILD (SAM-ILD) presents significant variations according to geographic location and temporal trends and is associated with increased morbidity and mortality. Several myositis autoantibodies have been discovered over the last decades, including antibodies targeting aminoacyl-tRNA synthetase enzymes, which are associated with a variable risk of developing ILD and a myriad of other clinical features. In this review, the most relevant topics regarding clinical manifestations, risk factors, diagnostic tests, autoantibodies, treatment, and prognosis of SAM-ILD are highlighted. We searched PubMed for relevant articles published in English, Portuguese, or Spanish from January 2002 to September 2022. The most common SAM-ILD patterns are nonspecific interstitial pneumonia and organizing pneumonia. The combination of clinical, functional, laboratory, and tomographic features is usually sufficient for diagnostic confirmation, without the need for additional invasive methods. Glucocorticoids remain the first-line treatment for SAM-ILD, although other traditional immunosuppressants, such as azathioprine, mycophenolate, and cyclophosphamide have demonstrated some efficacy and, therefore, have an important role as steroid-sparing agents.


Assuntos
Doenças Pulmonares Intersticiais , Miosite , Humanos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/etiologia , Pulmão , Imunossupressores/uso terapêutico , Miosite/complicações , Miosite/diagnóstico , Miosite/tratamento farmacológico , Autoanticorpos , Estudos Retrospectivos
2.
Sci Rep ; 11(1): 1130, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441951

RESUMO

Boltzmann-Gibbs statistical mechanics applies satisfactorily to a plethora of systems. It fails however for complex systems generically involving nonlocal space-time entanglement. Its generalization based on nonadditive q-entropies adequately handles a wide class of such systems. We show here that scale-invariant networks belong to this class. We numerically study a d-dimensional geographically located network with weighted links and exhibit its 'energy' distribution per site at its quasi-stationary state. Our results strongly suggest a correspondence between the random geometric problem and a class of thermal problems within the generalised thermostatistics. The Boltzmann-Gibbs exponential factor is generically substituted by its q-generalisation, and is recovered in the [Formula: see text] limit when the nonlocal effects fade away. The present connection should cross-fertilise experiments in both research areas.

3.
Sci Rep ; 6: 35370, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27734943

RESUMO

Retinitis pigmentosa (RP), the most frequent form of inherited retinal dystrophy is characterized by progressive photoreceptor degeneration. Many genes have been implicated in RP development, but several others remain to be identified. Using a combination of homozygosity mapping, whole-exome and targeted next-generation sequencing, we found a novel homozygous nonsense mutation in SAMD11 in five individuals diagnosed with adult-onset RP from two unrelated consanguineous Spanish families. SAMD11 is ortholog to the mouse major retinal SAM domain (mr-s) protein that is implicated in CRX-mediated transcriptional regulation in the retina. Accordingly, protein-protein network analysis revealed a significant interaction of SAMD11 with CRX. Immunoblotting analysis confirmed strong expression of SAMD11 in human retina. Immunolocalization studies revealed SAMD11 was detected in the three nuclear layers of the human retina and interestingly differential expression between cone and rod photoreceptors was observed. Our study strongly implicates SAMD11 as novel cause of RP playing an important role in the pathogenesis of human degeneration of photoreceptors.


Assuntos
Proteínas do Olho/metabolismo , Proteínas de Homeodomínio/metabolismo , Distrofias Retinianas/genética , Retinose Pigmentar/genética , Transativadores/metabolismo , Idoso , Animais , Proteínas Correpressoras/metabolismo , Códon sem Sentido , Estudos de Coortes , Hibridização Genômica Comparativa , Consanguinidade , Análise Mutacional de DNA , Exoma , Feminino , Regulação da Expressão Gênica , Genes Recessivos , Homozigoto , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Mapeamento de Interação de Proteínas , Retina/metabolismo , Retina/fisiopatologia , Distrofias Retinianas/etiologia , Distrofias Retinianas/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Retinose Pigmentar/etiologia , Retinose Pigmentar/metabolismo , Espanha , Fatores de Transcrição/metabolismo
4.
Sci Rep ; 6: 27992, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27320047

RESUMO

Deep connections are known to exist between scale-free networks and non-Gibbsian statistics. For example, typical degree distributions at the thermodynamical limit are of the form , where the q-exponential form optimizes the nonadditive entropy Sq (which, for q → 1, recovers the Boltzmann-Gibbs entropy). We introduce and study here d-dimensional geographically-located networks which grow with preferential attachment involving Euclidean distances through . Revealing the connection with q-statistics, we numerically verify (for d = 1, 2, 3 and 4) that the q-exponential degree distributions exhibit, for both q and k, universal dependences on the ratio αA/d. Moreover, the q = 1 limit is rapidly achieved by increasing αA/d to infinity.

5.
Artigo em Inglês | MEDLINE | ID: mdl-23410297

RESUMO

The effects of an external force on a diffusive process subjected to a backbone structure are investigated by considering the system governed by a Fokker-Planck equation with drift terms. Our results show an anomalous spreading which may present different diffusive regimes connected to anomalous diffusion and stationary states.


Assuntos
Difusão , Modelos Químicos , Modelos Moleculares , Modelos Estatísticos , Simulação por Computador
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(1 Pt 1): 011147, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22400552

RESUMO

We investigate a generalized Langevin equation (GLE) in the presence of an additive noise characterized by the mixture of the usual white noise and an arbitrary one. This scenario lead us to a wide class of diffusive processes, in particular the ones whose noise correlation functions are governed by power laws, exponentials, and Mittag-Leffler functions. The results show the presence of different diffusive regimes related to the spreading of the system. In addition, we obtain a fractional diffusionlike equation from the GLE, confirming the results for long time.


Assuntos
Algoritmos , Difusão , Modelos Químicos , Modelos Moleculares , Modelos Estatísticos , Simulação por Computador
7.
J Colloid Interface Sci ; 367(1): 34-9, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22074689

RESUMO

Zeolite 4A (LTA) has been successfully synthesized by a hydrothermal method, where kaolin was used as silica and alumina source. The synthesized zeolite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser granulometry, and FTIR spectroscopy. XRD data from the Rietveld refinement method confirmed only one crystallographic phase. Zeolite A morphology was observed by SEM analysis, and it showed well-defined crystals with slightly different sizes but with the same cubic shape. Particle size distribution of the crystals was confirmed by laser granulometry, whereas FTIR spectroscopy revealed significant structural differences between the starting material and the final zeolite product used as water softener.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(2 Pt 1): 021131, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19792101

RESUMO

We obtain exact solutions and the survival probability for a Fokker-Planck equation subjected to the two-dimensional wedge domain. We consider a spatial dependence in the diffusion coefficient and the presence of external forces. The results show an anomalous spreading of the solution and, consequently, a nonusual behavior of the survival probability which can be connected to anomalous diffusion.

9.
Lett Appl Microbiol ; 44(6): 607-12, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17576221

RESUMO

AIMS: To investigate the prevalence and characteristics of Shiga toxin-producing Escherichia coli (STEC) in cattle from Paraná State, southern Brazil. METHODS AND RESULTS: One hundred and seven faeces cattle samples were cultured on Sorbitol-MacConkey agar. Escherichia coli colonies were tested for production of Shiga toxin using Vero-cell assay. A high prevalence (57%) of STEC was found. Sixty-four STEC were serotyped and examined for the presence of stx(1), stx(2), eae, ehxA and saa genes and stx(2) variants. The isolates belonged to 31 different serotypes, of which three (O152:H8, O175:H21 and O176:H18) had not previously been associated with STEC. A high prevalence of stx(2)-type genes was found (62 strains, 97%). Variant forms found were stx(2), stx(2c), stx(2vhb), stx(2vO111v/OX393) and a form nonclassifiable by PCR-RFLP. The commonest genotypes were stx(2)ehxA saa and stx(1)stx(2)ehxA saa. CONCLUSIONS: A high frequency of STEC was observed. Several strains belong to serotypes previously associated with human disease and carry stx(2) and other virulence factors, thus potentially representing a risk to human health. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study of STEC in Paraná State, and its findings emphasize the need for proper cattle handling to prevent human contamination.


Assuntos
Bovinos/microbiologia , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Toxinas Shiga/biossíntese , Animais , Brasil , Chlorocebus aethiops , Escherichia coli/patogenicidade , Fezes/microbiologia , Genótipo , Carne , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sorotipagem , Toxinas Shiga/genética , Células Vero , Virulência/genética
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(3 Pt 1): 032101, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16605577

RESUMO

We investigate the solutions and first passage time distribution for an anomalous diffusion process governed by a generalized non-Markovian Fokker-Planck equation. In our analysis, we also consider the presence of external forces and absorbent (source) terms. In addition, we show that a rich class of diffusive processes, including normal and anomalous ones, can be obtained from the solutions found here.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(5 Pt 1): 052101, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16089577

RESUMO

We investigate an N-dimensional fractional diffusion equation with radial symmetry by using the Green function approach. We consider, in our analysis, the spatial dependence on the diffusion coefficient and the presence of an external force. In particular, we employ boundary conditions in a finite interval and after we extend it to a semi-infinite interval. We also show that a rich class of diffusive processes, including normal and anomalous ones, can be obtained from the solutions found here.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(5 Pt 1): 051109, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12786136

RESUMO

We analyze a nonlinear fractional diffusion equation with absorption by employing fractional spatial derivatives and obtain some more exact classes of solutions. In particular, the diffusion equation employed here extends some known diffusion equations such as the porous medium equation and the thin film equation. We also discuss some implications by considering a diffusion coefficient D(x,t)=D(t)/x/(-theta) (theta in R) and a drift force F=-k(1)(t)x+k(alpha)x/x/(alpha-1). In both situations, we relate our solutions to those obtained within the maximum entropy principle by using the Tsallis entropy.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 1): 011104, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11461222

RESUMO

Motivated by the self-similar character of energy spectra demonstrated for quasicrystals, we investigate the case of multifractal energy spectra, and compute the specific heat associated with simple archetypal forms of multifractal sets as generated by iterated maps. We considered the logistic map and the circle map at their threshold to chaos. Both examples show nontrivial structures associated with the scaling properties of their respective chaotic attractors. The specific heat displays generically log-periodic oscillations around a value that characterizes a single exponent, the "fractal dimension," of the distribution of energy levels close to the minimum value set to 0. It is shown that when the fractal dimension and the frequency of log oscillations of the density of states are large, the amplitude of the resulting log oscillation in the specific heat becomes much smaller than the log-periodic oscillation measured on the density of states.

14.
Peptides ; 20(6): 679-86, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10477123

RESUMO

Different peptides were purified by chromatographic procedures from the skin-secretory glands of the frog Phyllomedusa distincta. These are the first peptides reported from this frog species. Their primary structure was determined by a combination of automated Edman degradation and mass spectrometry. Peptide Q2 contains 25 amino acid residues, peptide Q1 and L have 28 each, peptide M contains 31, and peptide K has 33 amino acid residues. They all showed potent antimicrobial activity against Gram-negative and Gram-positive bacteria, presenting minimal inhibitory concentrations from 0.6 to 40 microM, when tested against Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Peptides K, L, and Q1 were chemically synthesized and shown to be active.


Assuntos
Antibacterianos/isolamento & purificação , Peptídeos , Pele/química , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/farmacologia , Anuros , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
15.
Braz J Med Biol Res ; 32(8): 961-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10454757

RESUMO

The short chain fatty acids (SCFA) are the best nutrients for the colonocytes. Glucose is poorly used as a fuel but may be transformed into SCFA by colonic bacteria. The aim of this study was to investigate the effect of SCFA or glucose on experimental colitis. Colitis was induced in 30 Wistar rats by colonic instillation of 4% acetic acid. Five days later they were randomized to receive twice a day colonic lavage containing saline (controls, N = 10), 10% hypertonic glucose (N = 10) or SCFA (N = 10) until day 8 when they were killed. At autopsy, the colon was removed and weighed and the mucosa was evaluated macro- and microscopically and stripped out for DNA assay. Data are reported as mean +/- SD or median [range] as appropriate. All animals lost weight but there was no difference between groups. Colon weight was significantly lower in the SCFA group (3.8 +/- 0.5 g) than in the control (5.3 +/- 2.1 g) and glucose (5.2 +/- 1.3 g) groups (P<0.05). Macroscopically, the severity of inflammation was less in SCFA (grade 2 [1-5]) than in control (grade 9 [4-10]) and glucose-treated (grade 9 [2-10]) animals (P<0.01). Microscopically, ulceration of the mucosa was more severe in the glucose and control groups than in the SCFA group. The DNA content of the mucosa of SCFA-treated animals (8.2 [5.0-20.2] mg/g of tissue) was higher than in glucose-treated (5.1 [4.2-8.5] mg/g of tissue; P<0.01) and control (6.2 [4.5-8.9] mg/g of tissue; P<0.05) animals. We conclude that SCFA may enhance mucosal re-epithelialization in experimental colitis, whereas hypertonic glucose is of no benefit.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Ácidos Graxos Voláteis/uso terapêutico , Mucosa Intestinal/efeitos dos fármacos , Ácido Acético , Animais , Colite Ulcerativa/induzido quimicamente , Epitélio/efeitos dos fármacos , Ácidos Graxos Voláteis/farmacologia , Solução Hipertônica de Glucose/uso terapêutico , Masculino , Ratos , Ratos Wistar , Estatísticas não Paramétricas
16.
Braz. j. med. biol. res ; 32(8): 961-6, Aug. 1999.
Artigo em Inglês | LILACS | ID: lil-238964

RESUMO

The short chain fatty acids (SCFA) are the best nutrients for the colonocytes. Glucose is poorly used as a fuel but may be transformed into SCFA by colonic bacteria. The aim of this study was to investigate the effect of SCFA or glucose on experimental colitis. Colitis was induced in 30 Wistar rats by colonic instillation of 4 percent acetic acid. Five days later they were randomized to receive twice a day colonic lavage containing saline (controls, N = 10), 10 percent hypertonic glucose (N = 10) or SCFA (N = 10) until day 8 when they were killed. At autopsy, the colon was removed and weighed and the mucosa was evaluated macro- and microscopically and stripped out for DNA assay. Data are reported as mean + or -SD or median [range] as appropriate. All animals lost weight but there was no difference between groups. Colon weight was significantly lower in the SCFA group (3.8 + or - 0.5 g) than in the control (5.3 + or - 2.1 g) and glucose (5.2 + or - 1.3 g) groups (PP<0.05). Macroscopically, the severity of inflammation was less in SCFA (grade 2 [1-5]) than in control (grade 9 [4-10]) and glucose-treated (grade 9 [2-10]) animals (P<0.01). Microscopically, ulceration of the mucosa was more severe in the glucose and control groups than in the SCFA group. The DNA content of the mucosa of SCFA-treated animals (8.2 [5.0-20.2] mg/g of tissue) was higher than in glucose-treated (5.1 [4.2-8.5] mg/g of tissue; P<0.01) and control (6.2 [4.5-8.9] mg/g of tissue; P<0.05) animals. We conclude that SCFA may enhance mucosal re-epithelialization in experimental colitis, whereas hypertonic glucose is of no benefit


Assuntos
Animais , Masculino , Ratos , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Ácidos Graxos Voláteis/uso terapêutico , Mucosa Intestinal/efeitos dos fármacos , Ácido Acético , Colite Ulcerativa/induzido quimicamente , Epitélio/efeitos dos fármacos , Ácidos Graxos Voláteis/farmacologia , Solução Hipertônica de Glucose/uso terapêutico , Ratos Wistar , Estatísticas não Paramétricas
17.
Arq Gastroenterol ; 29(3): 106-9, 1992.
Artigo em Português | MEDLINE | ID: mdl-1307209

RESUMO

The clinical and pathological manifestations of a case of carcinosarcoma of the esophagus are reported. Barium swallow and endoscopy revealed a polypoid mass in mid esophagus. The tumor was large, pedunculated, covered by smooth mucosa with some erosions. Histologically the tumor was composed of a mixture of invasion keratinizing cells and intermingled bundle of spindle shaped cells resembling fibrosarcoma. The tumor was removed with surgery and did not show submucosa infiltration. It was not detected any metastasis or local recurrence during the 12 months follow-up period. The diagnosis was made by an endoscopic partial polypectomy. We conclude that partial polypectomy may be of value in preoperative diagnosis of esophageal polypoid mass.


Assuntos
Carcinossarcoma/diagnóstico , Neoplasias Esofágicas/diagnóstico , Pólipos/diagnóstico , Carcinossarcoma/patologia , Carcinossarcoma/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagoplastia , Esofagoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos/patologia , Pólipos/cirurgia
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