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2.
Multimed Tools Appl ; : 1-24, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37362729

RESUMEN

In recent years, there has been a surge in the use of deep learning systems for e-healthcare applications. While these systems can provide significant benefits regarding improved diagnosis and treatment, they also pose substantial privacy risks to patients' sensitive data. Privacy is a crucial issue in e-healthcare, and it is essential to keep patient information secure. A new approach based on multi-agent-based privacy metrics for e-healthcare deep learning systems has been proposed to address this issue. This approach uses a combination of deep learning and multi-agent systems to provide a more robust and secure method for e-healthcare applications. The multi-agent system is designed to monitor and control the access to patients' data by different agents in the system. Each agent is assigned a specific role and has specific data access permissions. The system employs a set of privacy metrics to a substantial privacy level of the data accessed by each agent. These metrics include confidentiality, integrity, and availability, evaluated in real-time and used to identify potential privacy violations. In addition to the multi-agent system, the deep learning component is also integrated into the system to improve the accuracy of diagnoses and treatment plans. The deep learning model is trained on a large dataset of medical records and can accurately predict the diagnosis and treatment plan based on the patient's symptoms and medical history. The multi-agent-based privacy metrics for the e-healthcare deep learning system approach have several advantages. It provides a more secure system for e-healthcare applications by ensuring only authorized agents can access patients' data. Privacy metrics enable the system to identify potential privacy violations in real-time, thereby reducing the risk of data breaches. Finally, integrating deep learning improves the accuracy of diagnoses and treatment plans, leading to better patient outcomes.

3.
Trop Anim Health Prod ; 54(3): 160, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35426520

RESUMEN

A study was conducted to investigate the effects of zinc proteinate (Zn-P) on laying performance, egg quality, antioxidant indices, and egg zinc content in laying hens from 38 to 49 weeks of age. A total of 150 White Leghorn layers were randomly assigned to five treatments, each with six replicates with five birds per replication. Dietary treatments included a corn-soybean meal-based basal diet with no zinc addition and basal diet supplemented with Zn-P at 40, 80, 120, or 160 mg/kg of feed for 12 weeks. The analyzed zinc concentrations of the five diets were 29.5, 70.8, 110.2, 147.5, and 187.5 mg Zn/kg, respectively. Dietary Zn-P supplementation had no effect on feed intake and egg production. However, raising the zinc level improved egg weight (P < 0.01) and egg mass (P < 0.05) and lowered the feed conversion ratio (P < 0.05) during the later (46-49 weeks) period. The Zn-P supplementation also significantly (P < 0.05) increased Haugh units, egg shell strength, and shell thickness and had no influence on other egg quality parameters. Increasing zinc levels in the diet resulted in increase in egg zinc contents and serum zinc level. The serum triglyceride and LDL-cholesterol levels significantly decreased (P < 0.05) in Zn-P-supplemented groups. Supplementation of Zn-P significantly (P < 0.05) increased serum Cu-Zn-SOD activity and reduced MDA concentration. It could be concluded that dietary supplementation of higher levels of Zn-P, more than 80 mg/kg diet, significantly improved the egg zinc content, some egg quality traits, antioxidant activity, and serum zinc levels.


Asunto(s)
Pollos , Zinc , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Pollos/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Cáscara de Huevo/metabolismo , Femenino , Óvulo
4.
Lett Appl Microbiol ; 75(2): 308-316, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35435269

RESUMEN

Coffee wastewater contains large amounts of caffeine which affects microflora and seed development to great extent. Although several physio-chemical methods available for caffeine degradation, they are not preferred for large-scale treatment. In this study, we optimized induced cell concentration, aeration and agitation rate for maximizing caffeine degradation rate in bioreactor using Uniform design. Maximum caffeine degradation rate of 23·59 mg L-1 h-1 was achieved. The reduction in chemical oxygen demand, biological oxygen demand and total organic carbon removal were found to be 72, 78 and 72% respectively. Mathematical model was developed through regression analysis and predicted maximum caffeine degradation rate of 24·2 mg L-1 h-1 under optimal conditions of 0·35 g L-1 biomass, 395 rev min-1 and 1·62 vvm. Experimental validation at optimum condition resulted in 22 mg L-1 h-1 of caffeine degradation rate. This is the first-ever bioreactor study showing highest caffeine degradation rate in synthetic coffee wastewater with limited experimental runs.


Asunto(s)
Cafeína , Aguas Residuales , Biomasa , Reactores Biológicos , Café , Aguas Residuales/análisis
5.
Sci Rep ; 12(1): 1191, 2022 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-35075178

RESUMEN

Cholesterol is synthesized in chicken through de novo lipid biosynthetic pathway where two most important genes viz. SREBP1 and ACACA play immense role. To minimize cholesterol synthesis, RNAi approach was adopted and accordingly, we developed transgenic chicken possessing ACACA and SREBP1 shRNA constructs, which showed lower level of ACACA and SREBP1 in serum. The serum total cholesterol, triglycerides, HDL and LDL cholesterol was significantly lower by 23.8, 35.6, 26.6 and 20.9%, respectively in SREBP1 transgenic birds compared to the control. The egg total cholesterol and LDL cholesterol content was numerically lower in both ACACA and SREBP1 transgenic birds by 14.3 and 13.2%, and 10.4 and 13.7%, respectively compared to the control. It is concluded that the protocol was perfected to develop transgenic chicken through RNAi for knocking down the expression of ACACA and SREBP1 proteins, which minimized the cholesterol and triglycerides contents in serum and eggs.


Asunto(s)
Acetil-CoA Carboxilasa/genética , Pollos/genética , Colesterol/sangre , Huevos , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Animales , Animales Modificados Genéticamente/sangre , Pollos/sangre , Pollos/crecimiento & desarrollo , Femenino , Masculino , Progesterona/sangre , Interferencia de ARN , Análisis de Semen
6.
World J Clin Cases ; 9(31): 9333-9349, 2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34877270

RESUMEN

Inflammation is one of the primary factors associated with the causation and/or progression of several lifestyle disorders, including obesity, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). NAFLD is a spectrum of disorders, and starts with simple steatosis, progresses to non-alcoholic steatohepatitis, and then advances to fibrosis, cirrhosis and finally, hepatocellular carcinoma, due to perpetual cycles of insults caused by inflammation and other cellular stress. Emerging evidence has documented that patients with NAFLD have severe coronavirus disease 2019 (COVID-19), and patients with COVID-19 have a higher liver injury and mortality. Although the exact cause or mechanism is not known, inflammatory cytokine storm is a characteristic feature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and is known to be associated with higher mortality among COVID-19 patients. Therefore, the COVID-19 pandemic seems to be a major concern in NAFLD patients, who have contracted SARS-CoV-2 infection and develop COVID-19. This is evident in patients at any stage of the NAFLD spectrum, as the inflammatory cytokine storm may cause and/or aggravate the progression or severity of NAFLD. Thus, there is a need for resolution of the inflammatory cytokine storm in these patients. A large body of evidence has demonstrated the efficacy of omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) in NAFLD conditions, due to their anti-inflammatory, immunomodulatory and anti-viral properties. Therefore, intervention with ω-3 LCPUFA, an effective pharmaconutrient along with the standard treatment for COVID-19 may be useful in the management of the NAFLD spectrum in COVID-19 patients with pre-existing NAFLD conditions by resolving the inflammatory cytokine storm and thereby attenuating its progression. Although there are challenges in implementation, optimistically they can be circumvented and the pharmaconutrition strategy may be potentially helpful in tackling both the pandemics; NAFLD and COVID-19 at least in this subset of patients.

7.
Nat Commun ; 11(1): 1533, 2020 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-32210228

RESUMEN

Phenotypic heterogeneity exists within collectively invading packs of tumor cells, suggesting that cellular subtypes cooperate to drive invasion and metastasis. Here, we take a chemical biology approach to probe cell:cell cooperation within the collective invasion pack. These data reveal metabolic heterogeneity within invasive chains, in which leader cells preferentially utilize mitochondrial respiration and trailing follower cells rely on elevated glucose uptake. We define a pyruvate dehydrogenase (PDH) dependency in leader cells that can be therapeutically exploited with the mitochondria-targeting compound alexidine dihydrochloride. In contrast, follower cells highly express glucose transporter 1 (GLUT1), which sustains an elevated level of glucose uptake required to maintain proliferation. Co-targeting of both leader and follower cells with PDH and GLUT1 inhibitors, respectively, inhibits cell growth and collective invasion. Taken together, our work reveals metabolic heterogeneity within the lung cancer collective invasion pack and provides rationale for co-targeting PDH and GLUT1 to inhibit collective invasion.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Transportador de Glucosa de Tipo 1/metabolismo , Neoplasias Pulmonares/patología , Piruvato Deshidrogenasa (Lipoamida)/metabolismo , Animales , Comunicación Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Técnicas de Silenciamiento del Gen , Glucosa/metabolismo , Transportador de Glucosa de Tipo 1/antagonistas & inhibidores , Transportador de Glucosa de Tipo 1/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Invasividad Neoplásica/patología , Invasividad Neoplásica/prevención & control , Fosforilación Oxidativa , Piruvato Deshidrogenasa (Lipoamida)/antagonistas & inhibidores , Piruvato Deshidrogenasa (Lipoamida)/genética , ARN Interferente Pequeño/metabolismo , Esferoides Celulares
8.
Cell Biochem Funct ; 37(8): 578-590, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31495961

RESUMEN

Here, we tested a hypothesis that vitamin A and/or its metabolic pathways are involved in the high-fructose-mediated alteration in adipose tissue biology. For this purpose, weanling male Wistar rats were provided with one of the following diets: control (C), control with vitamin A deficiency (C-VAD), high fructose (HFr), and HFr with VAD (HFr-VAD) for 16 weeks, except that half of the C-VAD diet-fed rats were shifted to HFr diet (C-VAD(s)HFr), after 8-week period. Compared with control, feeding of HFr diet significantly increased the triglyceride content (P ≤ .01) and thus adipocyte size (hypertrophy) (P ≤ .001) in visceral adipose depot; retroperitoneal white adipose tissue (RPWAT) and these changes were corroborated with de novo lipogenesis, as evidenced by the increased glycerol-3-phosphate dehydrogenase activity (P ≤ .01) and up-regulation of lipogenic pathway transcripts, fructose transporter, and aldehyde dehydrogenase 1 A1. On the contrary, the absence of vitamin A in the HFr diet (HFr-VAD) failed to exert these changes; however, it induced adipocyte hyperplasia. Further, vitamin A deficiency-mediated changes were reversed by replenishment, as evident from the group that was shifted from C-VAD to HFr diet. In conclusion, vitamin A and its metabolic pathway play a key determinant role in the high-fructose-induced triglyceride accumulation and adipocyte hypertrophy of visceral white adipose depot. SIGNIFICANCE OF THE STUDY: Here, we report the metabolic impact of high-fructose feeding under vitamin A-sufficient and vitamin A-deficient conditions. Feeding of high-fructose diet induced triglyceride accumulation and adipocyte hypertrophy of the visceral white adipose depots. These changes corroborated with augmented expression of vitamin A and lipid metabolic pathway genes. Contrarily, absence of vitamin A in the high-fructose diet did not elicit such responses, while vitamin A replenishment reversed the changes exerted by vitamin A deficiency. To our knowledge, this is the first study to report the role of vitamin A and its metabolic pathway in the high-fructose-induced triglyceride synthesis and its accumulation in visceral adipose depot and thus provide a new insight and scope to understand these nutrients interaction in clinical conditions.


Asunto(s)
Fructosa/farmacología , Grasa Intraabdominal/efectos de los fármacos , Triglicéridos/metabolismo , Vitamina A/administración & dosificación , Adiponectina/análisis , Adiponectina/sangre , Animales , Diferenciación Celular/efectos de los fármacos , Dieta , Ácidos Grasos/análisis , Ácidos Grasos/química , Grasa Intraabdominal/citología , Grasa Intraabdominal/metabolismo , Leptina/análisis , Leptina/sangre , Lipogénesis/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Vitamina A/metabolismo , Deficiencia de Vitamina A/metabolismo , Deficiencia de Vitamina A/patología , Deficiencia de Vitamina A/veterinaria
9.
Int J Vitam Nutr Res ; 89(1-2): 62-72, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30957704

RESUMEN

The liver is the main site of lipid metabolism and vitamin A storage. Dietary factors are known to affect liver function, thereby leading to metabolic abnormalities. Here, we assessed the impact of long-term feeding of a high-fat diet on hepatic vitamin A status and lipid metabolism. For this purpose, 14 male and 14 female 35-day-old mice (strain C57BL/6J) were each divided into 2 groups of 7 animals and fed either a stock diet or a high-fat (HF) diet for 26 weeks. In addition to increased body weight/weight gain, the HF diet induced hypertriglyceridemia in both (p < 0.01). However, liver triglyceride levels were comparable among groups, which could be partly explained by unaltered expression of various lipogenic pathway proteins such as sterol regulatory element binding protein 1 (SREBP1), fatty acid synthase (FAS), microsomal triglyceride transfer protein (MTTP), and glycerol 3-phosphate acyl transferase (GPAT). On the other hand, hepatic retinol stores increased significantly in both sexes, whereas males displayed elevated circulatory retinol levels. Notably, long-term feeding of a HF diet elevated n-3 polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA, C22:6) levels in the liver (p ≤ 0.001), which is in line with the over-expression of very long-chain fatty acid elongase 2 (ELOVL2) protein in both sexes of mice (p < 0.01). In conclusion, very long-term feeding of a HF diet increased hepatic retinol stores and induced hypertriglyceridemia. However, it had no effect on hepatic triglyceride accumulation, possibly due to increased DHA levels arising from the ELOVL2-mediated elongation pathway.


Asunto(s)
Acetiltransferasas/metabolismo , Dieta Alta en Grasa , Ácidos Docosahexaenoicos , Hígado/fisiología , Acetiltransferasas/química , Animales , Elongasas de Ácidos Grasos , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL
10.
J Dent Res ; 98(7): 739-745, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31009580

RESUMEN

The oral cavity contains a rich consortium of exopolysaccharide-producing microbes. These extracellular polysaccharides comprise a major component of the oral biofilm. Together with extracellular proteins, DNA, and lipids, they form the biofilm matrix, which contributes to bacterial colonization, biofilm formation and maintenance, and pathogenesis. While a number of oral microbes have been studied in detail with regard to biofilm formation and pathogenesis, the exopolysaccharides have been well characterized for only select organisms, namely Streptococcus mutans and Aggregatibacter actinomycetemcomitans. Studies on the exopolysaccharides of other oral organisms, however, are in their infancy. In this review, we present the current research on exopolysaccharides of oral microbes regarding their biosynthesis, regulation, contributions to biofilm formation and stability of the matrix, and immune evasion. In addition, insight into the role of exopolysaccharides in biofilms is highlighted through the evaluation of emerging techniques such as pH probing of biofilm colonies, solid-state nuclear magnetic resonance for macromolecular interactions within biofilms, and super-resolution microscopy analysis of biofilm development. Finally, exopolysaccharide as a potential nutrient source for species within a biofilm is discussed.


Asunto(s)
Biopelículas , Boca/microbiología , Polisacáridos Bacterianos , Aggregatibacter actinomycetemcomitans , Humanos , Streptococcus mutans
11.
Br Poult Sci ; : 1-6, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30929462

RESUMEN

1. The effect of supplementing water-soluble vitamin E analogues 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (trolox) and butylated hydroxy toluene (BHT) was studied in two separate experiments. 2. In the first experiment, trolox was supplemented at 0.2 mM, 0.4 mM and 0.8 mM concentrations along with N-methylacetamide (MA; 12% final concentration) and semen was cryopreserved in 0.5 ml French straws. Different semen parameters and fertility were assessed from post-thaw samples. 3. Sperm motility, live sperm, and mitochondrial activity were significantly lower (P < 0.05) in cryopreserved semen. Lipid peroxidation (LPO) was significantly higher (P < 0.05) in cryopreserved semen that was reduced by trolox supplementation. The treatment containing trolox at 0.2 mM concentration produced significantly higher (P < 0.05) fertility compared to unsupplemented cryopreservation treatment. 4. In the second experiment, BHT was supplemented at 0.25 mM, 0.5 mM, and 1 mM concentrations along with MA during semen cryopreservation. 5. Sperm motility, live sperm and MTT dye reduction test were significantly lower (P < 0.05) in cryopreserved semen. These parameters declined with increasing BHT concentration. Abnormal sperm was significantly higher (P < 0.05) in the BHT supplemented treatments. The sperm chromatin dispersion (SCD) test was significantly higher (P < 0.05) in cryopreserved samples and was highest in samples supplemented with 0.5 mM and 1 mM BHT. The percentage fertility was significantly lower (P < 0.05) in cryopreserved semen and BHT supplementation did not improve fertility. 6. In conclusion, trolox supplementation at 0.2 mM concentration during semen cryopreservation improved fertility, whereas BHT supplementation resulted in a decline in post-thaw semen parameters.

14.
Anim Biotechnol ; 29(1): 20-25, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-28350488

RESUMEN

The effects of supplementing the organic forms of selenium (Se), chromium (Cr), and zinc (Zn) on Hsp-70 mRNA expression and body weight in broiler chickens were evaluated. 200 chicks were equally distributed into stainless steel battery brooders at the rate of 5 birds per pen and reared under heat stress condition up to 42nd day. The chicks were fed with three experimental diets supplemented with organic forms of Se (0.30 mg/kg), Cr (2 mg/kg), and Zn (40 mg/kg) during the starter and finisher phases and a control diet without any supplementation. On the 21st and 42nd day, 20 birds from each period were sacrificed and samples were collected for analysis. Organic Se, Cr, and Zn supplementation significantly (P < 0.05) reduced the expression of Hsp-70 mRNA levels. The Hsp-70 mRNA expression levels were significantly (P < 0.05) different between the tissues studied with spleen having the lowest expression level. Hsp-70 mRNA expression level was not affected by age of the birds. The study concluded that organic trace mineral (oTM) supplementation resulted in low Hsp-70 mRNA expression, indicating reduced heat stress in broilers.


Asunto(s)
Pollos/metabolismo , Suplementos Dietéticos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Proteínas del Choque Térmico HSP72/metabolismo , Respuesta al Choque Térmico/efectos de los fármacos , Respuesta al Choque Térmico/fisiología , Oligoelementos/administración & dosificación , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Femenino , Regulación Enzimológica de la Expresión Génica/fisiología , Proteínas del Choque Térmico HSP72/genética , ARN Mensajero/metabolismo , Distribución Tisular , Resultado del Tratamiento
15.
Cell Stress Chaperones ; 23(2): 235-252, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28842808

RESUMEN

Thermal manipulation during embryogenesis has been demonstrated to enhance the thermotolerance capacity of broilers through epigenetic modifications. Heat shock proteins (HSPs) are induced in response to stress for guarding cells against damage. The present study investigates the effect of thermal conditioning during embryogenesis and thermal challenge at 42 days of age on HSP gene and protein expression, DNA methylation and in vitro luciferase assay in brain tissue of Naked Neck (NN) and Punjab Broiler-2 (PB-2) chicken. On the 15th day of incubation, fertile eggs from two breeds, NN and PB-2, were randomly divided in to two groups: control (C)-eggs were incubated under standard incubation conditions, and thermal conditioning (TC)-eggs were exposed to higher incubation temperature (40.5°C) for 3 h on the 15th, 16th, and 17th days of incubation. The chicks obtained from each group were further subdivided and reared under different environmental conditions from the 15th to the 42nd day as normal [N; 25 ± 1 °C, 70% relative humidity (RH)] and heat exposed (HE; 35 ± 1 °C, 50% RH) resulting in four treatment groups (CN, CHE, TCN, and TCHE). The results revealed that HSP promoter activity was stronger in CHE, which had lesser methylation and higher gene expression. The activity of promoter region was lesser in TCHE birds that were thermally manipulated at the embryonic stage, thus reflecting their stress-free condition. This was confirmed by the lower level of mRNA expression of all the HSP genes. In conclusion, thermal conditioning during embryogenesis has a positive impact and improves chicken thermotolerance capacity in postnatal life.


Asunto(s)
Pollos/genética , Metilación de ADN/genética , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Respuesta al Choque Térmico/genética , Animales , Peso Corporal , Encéfalo/embriología , Encéfalo/metabolismo , Embrión de Pollo , Proteínas de Choque Térmico/metabolismo , Hormonas/sangre , Luciferasas/metabolismo , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
16.
Prev Nutr Food Sci ; 22(3): 172-183, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29043214

RESUMEN

Vitamin A and its metabolites modulate insulin resistance and regulate stearoyl-CoA desaturase 1 (SCD1), which are also known to affect insulin resistance. Here, we tested, whether vitamin A-mediated changes in insulin resistance markers are associated with SCD1 regulation or not. For this purpose, 30-week old male lean and glucose-intolerant obese rats of WNIN/GR-Ob strain were given either a stock or vitamin A-enriched diet, i.e. 2.6 mg or 129 mg vitamin A/kg diet, for 14 weeks. Compared to the stock diet, vitamin A-enriched diet feeding improved hyperglycemia and glucose-clearance rate in obese rats and no such changes were seen in lean rats receiving identical diets. These changes were corroborated with concomitant increase in circulatory insulin and glycogen levels of liver and muscle (whose insulin signaling pathway genes were up-regulated) in obese rats. Further, the observed increase in muscle glycogen content in these obese rats could be explained by increased levels of the active form of glycogen synthase, the key regulator of glycogen synthesis pathway, possibly inactivated through increased phosphorylation of its upstream inhibitor, glycogen synthase kinase. However, the unaltered hepatic SCD1 protein expression (despite decreased mRNA level) and increased muscle-SCD1 expression (both at gene and protein levels) suggest that vitamin A-mediated changes on glucose metabolism are not associated with SCD1 regulation. Chronic consumption of vitamin A-enriched diet improved hyperglycemia and glucose-intolerance, possibly, through the regulation of intracellular signaling and glycogen synthesis pathways of muscle and liver, but not associated with SCD1.

17.
Mol Oral Microbiol ; 32(6): 500-510, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28548373

RESUMEN

Aggregatibacter actinomycetemcomitans, a Gram-negative bacterium, is the causative agent of localized aggressive periodontitis. Attachment to a biotic surface is a critical first step in the A. actinomycetemcomitans infection process for which exopolysaccharides have been shown to be essential. In addition, the pga operon, containing genes encoding for biosynthetic proteins for poly-N-acetyl glucosamine (PNAG), plays a key role in A. actinomycetemcomitans virulence, as a mutant strain lacking the pga operon induces significantly less bone resorption. Among the genes in the pga operon, pgaB codes for a de-N-acetylase that is responsible for the deacetylation of the PNAG exopolysaccharide. Here we report the role of PgaB in regulation of virulence genes using a markerless, scarless deletion mutant targeting the coding region of the N-terminal catalytic domain of PgaB. The results demonstrate that the N-terminal, catalytic domain of PgaB is crucial for exopolysaccharide export.


Asunto(s)
Acetilesterasa/genética , Acetilesterasa/fisiología , Aggregatibacter actinomycetemcomitans/enzimología , Aggregatibacter actinomycetemcomitans/genética , Aggregatibacter actinomycetemcomitans/metabolismo , Genes Bacterianos/genética , Acetilglucosamina/inmunología , Acetilglucosamina/metabolismo , Aggregatibacter actinomycetemcomitans/patogenicidad , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Biopelículas/crecimiento & desarrollo , Dominio Catalítico , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Sistemas de Lectura Abierta/genética , Operón , Periodontitis , Polisacáridos Bacterianos , Eliminación de Secuencia , Virulencia/genética
18.
J Sci Food Agric ; 97(5): 1582-1591, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27417700

RESUMEN

BACKGROUND: Adipose tissue, an endocrine organ, plays a vital role not only in energy homeostasis, but also in the development and/or progression of various metabolic diseases, such as insulin resistance, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD), via several factors and mechanisms, including inflammation. This study tested, whether carrot juice administration affected the adipose tissue development and its inflammatory status in a high fructose diet-induced rat model. For this purpose, male weanling Wistar rats were divided into four groups and fed either control or high fructose diet of AIN-93G composition with or without carrot juice ingestion for an 8 week period. RESULTS: Administration of carrot juice did not affect the adiposity and cell size of visceral fat depot; retroperitoneal white adipose tissue (RPWAT), which was corroborated with unaltered expression of genes involved in adipogenic and lipogenic pathways. However, it significantly reduced the high fructose diet-induced elevation of plasma free fatty acid (FFA) (P ≤ 0.05), macrophage chemoattractant protein 1 (MCP1) (P ≤ 0.01) and high sensitive C-reactive protein (hsCRP) (P ≤ 0.05) levels. CONCLUSION: Carrot juice administration attenuated the high fructose diet-induced elevation of levels of circulatory FFA and pro-inflammatory mediators; MCP1 and hsCRP without affecting the adiposity and cell size of visceral fat depot; RPWAT. © 2016 Society of Chemical Industry.


Asunto(s)
Daucus carota , Fructosa/efectos adversos , Jugos de Frutas y Vegetales , Adiposidad/efectos de los fármacos , Animales , Proteína C-Reactiva/efectos de los fármacos , Factores Quimiotácticos/efectos adversos , Dieta , Ácidos Grasos no Esterificados/sangre , Mediadores de Inflamación/efectos adversos , Grasa Intraabdominal/citología , Grasa Intraabdominal/efectos de los fármacos , Masculino , Ratas Wistar
19.
Mol Oral Microbiol ; 32(4): 324-340, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27706922

RESUMEN

The oral pathogen Aggregatibacter actinomycetemcomitans uses pga gene locus for the production of an exopolysaccharide made up of a linear homopolymer of ß-1,6-N-acetyl-d-glucosamine (PGA). An enzyme encoded by the pgaB of the pga operon in A. actinomycetemcomitans is a de-N-acetylase, which is used to alter the PGA. The full length enzyme (AaPgaB) and the N-terminal catalytic domain (residues 25-290, AaPgaBN) from A. actinomycetemcomitans were cloned, expressed and purified. The enzymatic activities of the AaPgaB enzymes were determined using 7-acetoxycoumarin-3-carboxylic acid as the substrate. The AaPgaB enzymes displayed significantly lower de-N-acetylase activity compared with the activity of the deacetylase PdaA from Bacillus subtilis, a member of the CE4 family of enzymes. To delineate the differences in the activity and the active site architecture, the structure of AaPgaBN was determined. The AaPgaBN structure has two metal ions in the active site instead of one found in other CE4 enzymes. Based on the crystal structure comparisons among the various CE4 enzymes, two residues, Q51 and R271, were identified in AaPgaB, which could potentially affect the enzyme activity. Of the two mutants generated, Q51E and R271K, the variant Q51E showed enhanced activity compared with AaPgaB, validating the requirement that an activating aspartate residue in the active site is essential for higher activity. In summary, our study provides the first structural evidence for a di-nuclear metal site at the active site of a member of the CE4 family of enzymes, evidence that AaPgaBN is catalytically active and that mutant Q51E exhibits higher de-N-acetylase activity.


Asunto(s)
Acetilesterasa/química , Acetilesterasa/metabolismo , Aggregatibacter actinomycetemcomitans/enzimología , Acetilesterasa/genética , Acetilesterasa/aislamiento & purificación , Aggregatibacter actinomycetemcomitans/química , Aggregatibacter actinomycetemcomitans/genética , Aggregatibacter actinomycetemcomitans/patogenicidad , Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Dominio Catalítico , Cristalización , Cristalografía por Rayos X , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/aislamiento & purificación , Proteínas de Escherichia coli/metabolismo , Cinética , Metales/química , Modelos Moleculares , Mutación , Operón , Polisacáridos Bacterianos , Dominios Proteicos , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad
20.
Indian J Med Res ; 144(2): 238-244, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27934803

RESUMEN

BACKGROUND & OBJECTIVES: Hepatic scavenger receptor class B1 (SR-B1), a high-density lipoprotein (HDL) receptor, is involved in the selective uptake of HDL-associated esterified cholesterol (EC), thereby regulates cholesterol homoeostasis and improves reverse cholesterol transport. Previously, we reported in euglycaemic obese rats (WNIN/Ob strain) that feeding of vitamin A-enriched diet normalized hypercholesterolaemia, possibly through hepatic SR-B1-mediated pathway. This study was aimed to test whether it would be possible to normalize hypercholesterolaemia in glucose-intolerant obese rat model (WNIN/GR/Ob) through similar mechanism by feeding identical vitamin A-enriched diet. METHODS: In this study, 30 wk old male lean and obese rats of WNIN/GR-Ob strain were divided into two groups and received either stock diet or vitamin A-enriched diet (2.6 mg or 129 mg vitamin A/kg diet) for 14 wk. Blood and other tissues were collected for various biochemical analyses. RESULTS: Chronic vitamin A-enriched diet feeding decreased hypercholesterolaemia and normalized abnormally elevated plasma HDL-cholesterol (HDL-C) levels in obese rats as compared to stock diet-fed obese groups. Further, decreased free cholesterol (FC) and increased esterified cholesterol (EC) contents of plasma cholesterol were observed, which were reflected in higher EC to FC ratio of vitamin A-enriched diet-fed obese rats. However, neither lecithin-cholesterol acyltransferase (LCAT) activity of plasma nor its expression (both gene and protein) in the liver were altered. On the contrary, hepatic cholesterol levels significantly increased in vitamin A-enriched diet fed obese rats. Hepatic SR-B1 expression (both mRNA and protein) remained unaltered among groups. Vitamin A-enriched diet fed obese rats showed a significant increase in hepatic low-density lipoprotein receptor mRNA levels, while the expression of genes involved in HDL synthesis, namely, ATP-binding cassette protein 1 (ABCA1) and apolipoprotein A-I, were downregulated. No such response was seen in vitamin A-supplemented lean rats as compared with their stock diet-fed lean counterparts. INTERPRETATION & CONCLUSIONS: Chronic vitamin A-enriched diet feeding decreased hypercholesterolaemia and normalized HDL-C levels, possibly by regulating pathways involved in HDL synthesis and degradation, independent of hepatic SR-B1 in this glucose-intolerant obese rat model.


Asunto(s)
Colesterol/sangre , Hipercolesterolemia/sangre , Obesidad/sangre , Receptores Depuradores de Clase B/biosíntesis , Vitamina A/administración & dosificación , Transportador 1 de Casete de Unión a ATP/biosíntesis , Animales , Apolipoproteína A-I/biosíntesis , Transporte Biológico/genética , Colesterol/genética , HDL-Colesterol/biosíntesis , HDL-Colesterol/sangre , Dieta , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Hipercolesterolemia/dietoterapia , Hipercolesterolemia/genética , Hígado/metabolismo , Masculino , Redes y Vías Metabólicas/genética , Obesidad/dietoterapia , Obesidad/genética , Fosfatidilcolina-Esterol O-Aciltransferasa/sangre , Ratas , Receptores Depuradores de Clase B/genética , Vitamina A/metabolismo
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