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1.
Appl Opt ; 62(18): 4935-4941, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37707271

ABSTRACT

The half-adder is one of the most useful combinational logic functions for data processing. Many research papers in the literature propose nonlinear all-optical half-adders. Few studies propose linear all-optical devices, and those that do usually employ microstructured 2D photonic crystals. This work presents the numerical acquisition of an all-optical half-adder using a linear three-core fiber device. The device presents high performance and acceptable values of fabrication and modulation tolerance. It can be made using any fiber technology and propagated by pulses of any wavelength. Depending on the type of fiber used, the precision needed to fabricate the device's smallest structures can range from 20 nm to 90 nm. This result is evidence of the possibility of obtaining nonlinear logical processing using only fiber design.

2.
Appl Opt ; 61(28): 8515-8521, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-36256168

ABSTRACT

Digital multiplexers/demultiplexers (MUX/DEMUXes) are essential for computing, data transmission, and data processing. However, research on all-optical digital MUX/DEMUXes is scarce and generally proposes single-function nonlinear devices. This work presents the numerical acquisition of all-optical digital MUX/DEMUXes using a linear three-core fiber device. Our device, called the interchanging-cores planar three-core fiber coupler, is propagated by low-powered amplitude modulated pulses, can operate with pulses of any wavelength, and can be made using any fiber technology. This result is further evidence of the possibility of obtaining logical processing, even nonlinear logical processing, using fiber-only design.

3.
Appl Opt ; 60(29): 9225-9230, 2021 Oct 10.
Article in English | MEDLINE | ID: mdl-34624008

ABSTRACT

The growth of transmission rates in optical fibers can increase the demand for devices that perform network node processing. Usually, such devices achieve complex optical signal processing through high non-linearity effects and optoelectronic devices. In this work, we present the numerical acquisition of a configurable multi-function logic gate in which the OR and AND gates can be enabled based on the logic values entered in a selector. Our device consists of a single piece of three-core PCF, with linear pulse propagation, and without the need for any other mechanisms. This result presents evidence that information processing within functional fibers is possible and might be achieved using only fiber design.

4.
Dig Dis Sci ; 66(10): 3359-3374, 2021 10.
Article in English | MEDLINE | ID: mdl-33104937

ABSTRACT

BACKGROUND/AIM: A link between an impaired intestinal barrier, endotoxemia, and the pathogenesis of metabolic diseases, such as type 2 diabetes mellitus (T2DM), has been proposed. In previous work, we have demonstrated that the tight junction (TJ)-mediated intestinal barrier in ileum/colon was marginally changed in prediabetic mice; therefore, it does not seem to mainly contribute to the T2DM onset. In this study, the TJ-mediated epithelial barrier in the duodenum and jejunum was evaluated in mice during the development of type 2 prediabetes. METHODS/RESULTS: HF diet induced prediabetes after 60 days associated with a significant rise in intestinal permeability to the small-sized marker Lucifer yellow in these mice, with no histological signs of mucosal inflammation or rupture of the proximal intestine epithelium. As revealed by immunofluorescence, TJ proteins, such as claudins-1, -2, -3, and ZO-1, showed a significant decrease in junctional content in duodenum and jejunum epithelia, already after 15 days of treatment, suggesting a rearrangement of the TJ structure. However, no significant change in total cell content of these proteins was observed in intestinal epithelium homogenates, as assessed by immunoblotting. Despite the changes in intestinal permeability and TJ structure, the prediabetic mice showed similar LPS, zonulin, and TNF-α levels in plasma or adipose tissue, and in intestinal segments as compared to the controls. CONCLUSION: Disruption of the TJ-mediated paracellular barrier in the duodenum and jejunum is an early event in prediabetes development, which occurs in the absence of detectable endotoxemia/inflammation and may contribute to the HF diet-induced increase in intestinal permeability.


Subject(s)
Diabetes Mellitus, Type 2/chemically induced , Diet, High-Fat/adverse effects , Endotoxemia/chemically induced , Intestine, Small/drug effects , Intestine, Small/pathology , Tight Junctions/drug effects , Animals , Haptoglobins/metabolism , Intestinal Mucosa/drug effects , Lipopolysaccharides/blood , Lipopolysaccharides/metabolism , Male , Mice , Protein Precursors/blood , Protein Precursors/metabolism , Random Allocation , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/metabolism
5.
Braz J Med Biol Res ; 53(6): e9031, 2020.
Article in English | MEDLINE | ID: mdl-32401929

ABSTRACT

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1ß immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Subject(s)
Apolipoprotein A-I/blood , Diet/adverse effects , Inflammation/metabolism , Malnutrition/metabolism , Animals , Apolipoprotein A-I/metabolism , Brazil , Chronic Disease , Humans , Inflammation/blood , Inflammation/pathology , Liver/metabolism , Male , Malnutrition/blood , Malnutrition/pathology , Mice , Mice, Inbred C57BL
6.
Braz. j. med. biol. res ; 53(6): e9031, 2020. tab, graf
Article in English | LILACS, Coleciona SUS | ID: biblio-1132523

ABSTRACT

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1β immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Subject(s)
Humans , Animals , Male , Rabbits , Rats , Apolipoprotein A-I/blood , Malnutrition/metabolism , Diet/adverse effects , Inflammation/metabolism , Brazil , Chronic Disease , Apolipoprotein A-I/metabolism , Malnutrition/pathology , Malnutrition/blood , Inflammation/pathology , Inflammation/blood , Liver/metabolism , Mice, Inbred C57BL
7.
Arch Oral Biol ; 98: 204-212, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30503976

ABSTRACT

The association between cardiovascular and periodontal diseases is characterized by chronic inflammatory processes, with a high prevalence worldwide and complex genetic-environment interactions. Although apolipoprotein E4 (ApoE4), one of the isoforms coded by a polymorphic APOE gene, has been widely recognized as a risk factor for cardiovascular diseases and as an immunoinflammatory factor, less is known regarding how ApoE4 affects atherosclerosis in periodontitis patients. The aim of this review was to investigate the potential underlying mechanisms related to APOE4 that could increase the risk of periodontal disease and, ultimately, of atherosclerosis. There have only been a few studies addressing apoE polymorphisms in patients with chronic periodontitis. To date, no studies have been performed that have assessed how ApoE4 affects atherosclerotic disease in chronic periodontitis patients. Although clinical studies are warranted, experimental studies have consistently documented the presence of periodontal pathogens, which are usually found in the oral cavity and saliva, in the atherosclerotic plaques of ApoE-deficient mice. In addition, in this review, the potential role of the APOE4 allele as an example of antagonistic pleiotropy during human evolution and its relation to oral health is discussed.


Subject(s)
Apolipoproteins E/metabolism , Atherosclerosis/etiology , Periodontal Diseases/complications , Animals , Apolipoprotein E3/metabolism , Apolipoprotein E4 , Apolipoproteins E/genetics , Cardiovascular Diseases/etiology , Genetic Pleiotropy , Humans , Inflammation/etiology , Mice , Microbiota , Mouth , Polymorphism, Genetic , Protein Isoforms , Risk Factors
8.
Neurogastroenterol Motil ; 30(5): e13264, 2018 05.
Article in English | MEDLINE | ID: mdl-29266818

ABSTRACT

BACKGROUND: The intestinal mucosa plays an important role in the mechanical barrier against pathogens. During Toxoplasma gondii infection, however, the parasites invade the epithelial cells of the small intestine and initiate a local immune response. In the submucosal plexus, this response promotes an imbalance of neurotransmitters and induces neuroplasticity, which can change the integrity of the epithelium and its secretory function. This study evaluated the submucosal neurons throughout acute T. gondii infection and the relationship between possible alterations and the epithelial and immune defense cells of the mucosa. METHODS: Forty Wistar rats were randomly assigned to 8 groups (n = 5): 1 control group, uninfected, and 7 groups infected with an inoculation of 5000 sporulated T. gondii oocysts (ME-49 strain, genotype II). Segments of the ileum were collected for standard histological processing, histochemical techniques, and immunofluorescence. KEY RESULTS: The infection caused progressive neuronal loss in the submucosal general population and changed the proportion of VIPergic neurons throughout the infection periods. These changes may be related to the observed reduction in goblet cells that secret sialomucins and increase in intraepithelial lymphocytes after 24 hours, and the increase in immune cells in the lamina propria after 10 days of infection. The submucosa also presented fibrogenesis, characterizing injury and tissue repair. CONCLUSIONS AND INFERENCES: The acute T. gondii infection in the ileum of rats changes the proportion of VIPergic neurons and the epithelial cells, which can compromise the mucosal defense during infection.


Subject(s)
Goblet Cells/metabolism , Ileum/metabolism , Intraepithelial Lymphocytes/metabolism , Neurons/metabolism , Toxoplasmosis/metabolism , Vasoactive Intestinal Peptide/metabolism , Animals , Cell Count , Cell Death/physiology , Goblet Cells/microbiology , Goblet Cells/pathology , Ileum/microbiology , Ileum/pathology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Intraepithelial Lymphocytes/microbiology , Intraepithelial Lymphocytes/pathology , Male , Myenteric Plexus/metabolism , Myenteric Plexus/microbiology , Myenteric Plexus/pathology , Neurons/microbiology , Neurons/pathology , Rats , Rats, Wistar , Toxoplasma , Toxoplasmosis/microbiology , Toxoplasmosis/pathology
9.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1155-1162, set.-out. 2017. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-877312

ABSTRACT

Objetivou-se avaliar clinicamente os efeitos da administração intrarruminal de duas quantidades distintas de manga em ovinos. Foram utilizados sete ovinos machos, hígidos, que não receberam carboidratos não fibrosos por, pelo menos, seis meses previamente ao período experimental, quando se avaliou pH ruminal, total de protozoários no suco de rúmen, pH urinário, pH sanguíneo estimado e parâmetros vitais nos tempos zero, 12, 16, 20 e 24 após a administração da manga. Os sete ovinos foram distribuídos aleatoriamente em dois grupos e receberam 0,625% ou 1,875% da MS de manga/kg/PV (M1 e M2, respectivamente), distribuídos em delineamento cross-over, com uma parcela perdida, e 30 dias de washout. Os ovinos M2 apresentaram valores médios para pH ruminal significativamente inferiores a M1 a partir do tempo T12 (5,1 e 6,9, respectivamente), o que indica ocorrência de acidose ruminal. Os animais tratados com M1 não apresentaram alterações sistêmicas, ao passo que os ovinos tratados com M2 apresentaram acidose metabólica leve, detectada por meio do pH urinário ácido (4,8). A ingestão apenas de manga in natura na quantidade de 1,875% da MS de manga/kg/PV mostrou-se capaz de provocar acidose ruminal em ovinos, levando-os a: ligeira depressão, aumento da frequência cardíaca, diminuição dos movimentos ruminais e diarreia em alguns casos.(AU)


The aim of this study is to clinically evaluate the effects of intra ruminal administration of two different amounts of mango in sheep. The sample was of seven male healthy sheep, which did not receive non-fibrous carbohydrates for at least six months prior to the trial. Rumen fluid pH, total of protozoa in the rumen fluid, urine pH, estimated blood pH, and vital parameters were evaluated at the following times: zero, 12, 16, 20 and 24 hours after administration of the mango. The seven sheep were randomly divided into two groups and received either 0.625% or 1.875% of the dry matter of the pulp and mango peel per kg body weight (M1 and M2, respectively), distributed in cross-over design with a lost portion and 30 days washout. Sheep treated with M2 showed significantly lower average values for ruminal pH than the M1 since T12 (5.1 and 6.9, respectively), indicating the occurrence of ruminal acidosis. The animals treated with M1 showed no systemic changes, while the sheep treated with M2 had mild metabolic acidosis, detected through the lower urinary pH (4.8). The in natura mango ingestion in the amount of 1.875% of the dry matter of mango per kg of body weight proved to provoke rumen acidosis in sheep, leading these animals to: slight depression, rise in heart rate, diminished rumen movement, and diarrhea in some cases.(AU)


Subject(s)
Animals , Acidosis/veterinary , Mangifera , Rumen , Sheep/metabolism , Fruit
10.
Genet Mol Res ; 15(4)2016 Nov 21.
Article in English | MEDLINE | ID: mdl-27886338

ABSTRACT

Recently, the number of Aedes aegypti foci has increased in west of Santa Catarina, south Brazil, which has increased concern regarding mosquito-borne disease outbreaks such as dengue fever, Zika virus, and chikungunya. Therefore, it is important to monitor genetic resistance to insecticides through "knockdown resistance". Homozygosity (Ile/Ile) at position 1016 in the coding region of a voltage-dependent sodium channel gene (Nav) may induce resistance to pyrethroid insecticides. We evaluated the frequency of these alleles in A. aegypti in west Santa Catarina. In total, 349 specimens were obtained from the microregions of Joaçaba (31), Concórdia (35), Chapecó (154), and São Miguel do Oeste (129). We found that 109 individuals (31.0%) were homozygous for Val/Val, 102 (29.0%) were heterozygous for Val/Ile, and 138 (40.0%) were homozygous for Ile/Ile. The allele frequencies were similar for Val (0.455) and Ile (0.545). Joaçaba and Concórdia had the highest mutant allele frequencies (0.825 and 0.685, respectively). Therefore, these populations should be monitored for increases in pyrethroid resistance. The São Miguel do Oeste and Chapecó populations had similar frequencies of Val and Ile and were not in Hardy-Weinberg equilibrium, suggesting that a selection pressure or other evolutionary force has occurred. In conclusion, the observed frequency of Ile/Ile homozygous individuals in the region studied requires attention, because the implementation of controls using pyrethroid may increase the frequency of the mutant allele through the selection of resistant populations.


Subject(s)
Aedes/genetics , Insecticide Resistance , Mutation Rate , Sodium Channels/genetics , Animals , Brazil , Insect Proteins/genetics , Isoleucine/genetics , Mutation , Valine/genetics
11.
Comp Biochem Physiol A Mol Integr Physiol ; 147(3): 594-599, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17020813

ABSTRACT

The fruit fly Anastrepha fraterculus is a major pest of native and exotic fruit trees in South America. Changes in weight, water content and metabolism were observed during its ontogenetic development in standard conditions (25 degrees C, RH=60% and 14 h:10 h photoperiod). The metabolic variables glycogen, total proteins, triglycerides and total lipids were measured by means of spectrophotometric methods. The results were correlated with pupae metamorphosis, temporal pattern, and beginning of adult life. Pupae were observed daily, and a sub-sample of 10 individuals was collected and maintained at -20 degrees C. The same procedure was performed with adults at 4 days after adult eclosion. Levels of total lipids and triglycerides were constant during pupal development, peaking in 312-h-old pupae. In 0-h-old pupae, glycogen levels were high, and decreased progressively until the insects were 312 h old. The peak in total proteins coincides with the post-histolysis period of the larval tissue (96-120 h). These results indicated that glycogen and proteins may be the principal sources of energy for metamorphosis. Total lipid and triglyceride contents remained steady during metamorphosis, and these were consumed in the first 4 days of adult life.


Subject(s)
Tephritidae/growth & development , Tephritidae/metabolism , Animals , Body Weight , Glycogen/analysis , Insect Proteins/analysis , Pupa/chemistry , Pupa/growth & development , Triglycerides/analysis
12.
Acta Trop ; 99(2-3): 252-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17055444

ABSTRACT

Leishmaniasis is one of the most diverse and complex of all vector-borne diseases. Because it involves several overlapping species and sandfly vectors, the disease has a complex ecology and epidemiology. Adequate therapy and follow-up depend on parasitological diagnosis, but classical methods present several constraints when identifying species. We describe a polymerase chain reaction (PCR) which uses primers designed from mini-exon repetitive sequences that are specific for subgenus LeishmaniaViannia (PV), as well as sequences with specificity for genus (PG) that can distinguish between Leishmania species from other insect flagellates with minor differences in PCR products. For standardization, these PCR were tested in experimentally infected sandflies, and Leishmania infection in these insects was successfully confirmed. This methodology identified a 3.9% infection rate in field-captured phlebotomine sandflies from an endemic region in Brazil. Natural infection by Leishmania species was identified in three samples of Lutzomyia longipalpis, of which two were Leishmania (L.) chagasi and one Leishmania (L.) amazonensis. Irrespective of specific epidemiological conclusions, the method used in this study was able to identify Leishmania infections both in experimentally infected and field-captured phlebotomine sandflies, and could be a useful tool in epidemiological studies and strategic planning for the control of human leishmaniasis.


Subject(s)
Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmaniasis/parasitology , Phlebotomus/parasitology , Polymerase Chain Reaction/methods , Animals , Brazil , Cricetinae , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Exons , Female , Leishmania/genetics , Repetitive Sequences, Nucleic Acid/genetics
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