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1.
Br Poult Sci ; 64(6): 751-762, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37782109

RESUMO

1. It was hypothesised that dietary N-acetyl-L-cysteine (NAC) in feed, as a source of cysteine, could improve the performance of heat-stressed finisher broilers by fostering glutathione (GSH) synthesis. GSH is the most abundant intracellular antioxidant for which the sulphur amino acid cysteine is rate limiting for its synthesis.2. In the first experiment, four levels of NAC: 0, 500, 1000 and 2000 mg/kg were added to a diet with a suboptimal level of sulphur amino acids in the finisher phase. In the second experiment, NAC was compared to other sulphur amino acid sources at equal molar amounts of digestible sulphur amino acids. Birds were allocated to four groups: control, 2000 mg/kg NAC, 1479 mg/kg L-cystine, and 2168 mg/kg Ca-salt of 2-hydroxy-4-(methylthio)butanoic acid. A chronic cyclic heat stress model (temperature was increased to 34°C for 7 h daily) was initiated at 28 d of age.3. In the first experiment, growth performance and feed efficiency in the finisher phase were significantly improved by graded NAC. ADG was 88.9, 92.2, 93.7 and 97.7 g/d, and the feed-to-gain ratio was 2.18, 1.91, 1.85 and 1.81 for the 0, 500, 1000 and 2000 mg/kg NAC treatments, respectively. However, liver and heart GSH levels were not affected by NAC. On d 29, liver gene transcript of cystathionine-beta-synthase like was reduced by NAC, which suggested reduced trans-sulphuration activity. The second experiment showed that L-cystine and Ca-salt of 2-hydroxy-4-(methylthio) butanoic acid were more effective in improving performance than NAC.4. In conclusion, N-acetyl-L-cysteine improved dose-dependently growth and feed efficiency in heat-stressed finishing broilers. However, this was not associated with changes in tissue GSH levels, but more likely worked by sparing methionine and/or NAC's and cysteine's direct antioxidant properties.


Assuntos
Acetilcisteína , Aminoácidos Sulfúricos , Animais , Antioxidantes/metabolismo , Galinhas , Cistina , Glutationa , Dieta/veterinária , Resposta ao Choque Térmico , Butiratos , Suplementos Nutricionais , Ração Animal/análise
2.
Poult Sci ; 102(6): 102653, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37030259

RESUMO

Dietary guanidinoacetic acid (GAA) has been shown to affect creatine (Cr) metabolic pathways resulting in increased cellular Cr and hitherto broiler performances. Yet, the impact of dietary GAA on improving markers of oxidative status remains equivocal. A model of chronic cyclic heat stress, known to inflict oxidative stress, was employed to test the hypothesis that GAA could modify bird's oxidative status. A total of 720-day-old male Ross 308 broilers were allocated to 3 treatments: 0, 0.6 or 1.2 g/kg GAA was added to corn-SBM diets and fed for 39 d, with 12 replicates (20 birds each) per treatment. The chronic cyclic heat stress model (34°C with 50-60% RH for 7 h daily) was applied in the finisher phase (d 25-39). Samples from 1 bird per pen were taken on d 26 (acute heat stress) and d 39 (chronic heat stress). GAA and Cr in plasma were linearly increased by feeding GAA on either sampling day, illustrating efficient absorption and methylation, respectively. Energy metabolism in breast and heart muscle was greatly supported as visible by increased Cr and phosphocreatine: ATP, thus providing higher capacity for rapid ATP generation in cells. Glycogen stores in breast muscle were linearly elevated by incremental GAA, on d 26 only. More Cr seems to be directed to heart muscle as opposed to skeletal muscle during chronic heat stress as tissue Cr was higher in heart but lower in breast muscle on d 39 as opposed to d 26. The lipid peroxidation marker malondialdehyde, and the antioxidant enzymes superoxide dismutase and glutathione peroxidase showed no alterations by dietary GAA in plasma. Opposite to that, superoxide dismutase activity in breast muscle was linearly lowered when feeding GAA (trend on d 26, effect on d 39). Significant correlations between the assessed parameters and GAA inclusion were identified on d 26 and d 39 using principal component analysis. To conclude, beneficial performance in heat-stressed broilers by GAA is associated with enhanced muscle energy metabolism which indirectly may also support tolerance against oxidative stress.


Assuntos
Creatina , Suplementos Nutricionais , Animais , Masculino , Suplementos Nutricionais/análise , Creatina/metabolismo , Galinhas/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Estresse Oxidativo , Resposta ao Choque Térmico , Superóxido Dismutase/metabolismo , Trifosfato de Adenosina , Ração Animal/análise
3.
Trends Microbiol ; 30(5): 466-479, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34753652

RESUMO

Bacteria have at their disposal a battery of strategies to withstand antibiotic stress. Among these, resistance is a well-known mechanism, yet bacteria can also survive antibiotic attack by adopting a tolerant phenotype. In the case of persistence, only a small fraction within an isogenic population switches to this antibiotic-tolerant state. Persistence depends on the ecological niche and the genetic background of the strains involved. Furthermore, it has been shown to be under direct and indirect evolutionary pressure. Persister cells play a role in chronic infections and the development of resistance, and therefore a better understanding of this phenotype could contribute to the development of effective antibacterial therapies. In the current review, we discuss how ecological and evolutionary forces shape persistence.


Assuntos
Antibacterianos , Bactérias , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/genética , Fenótipo
4.
Animal ; 16(1): 100417, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34942568

RESUMO

Thymol α-D-glucopyranoside (TαG) and thymol ß-D-glucopyranoside (TßG) are believed to have different kinetic behaviours in the porcine gut than its parent aglycon thymol. However, recently, it was shown that concentrations of both glucosides decreased rapidly in the stomach and proximal small intestine following oral supplementation to piglets as did thymol. Yet, the stability of thymol glucosides in gut contents and their absorption route remains obscure. Therefore, a series of in vitro incubations were performed, simulating the impact of pH, digestive enzymes, bacterial activity and mucosal extracts on stability of these glucosides. Their absorption mechanisms were investigated using the Ussing chamber model in the presence or the absence of inhibitors of sodium-dependent glucose linked transporter 1 and lactase phlorizin hydrolase. Both glucosides remained intact at physiological pH levels in the presence of digestive enzymes. Recoveries from TαG and TßG were below 90% when incubated with small intestinal homogenates from the distal jejunum or from all sampled sites, respectively. However, no aglycon could be detected in these samples. Bacterial inoculum of the small intestine, on the other hand, hydrolysed TßG quickly with up to 44% of free aglycon appearing. TαG proved more resistant to porcine gastro-intestinal bacterial glucosidases with only trace amounts (<1%) of free thymol at the end of the incubations. Electrophysiological measurements in Ussing chambers did not suggest active transport of the glucosides. Mucosal TαG and TßG concentrations were unchanged between start and end of the absorption measurements. Additionally, no TαG and only a very limited amount of TßG were retrieved from the serosal side. Tissue associated concentrations, although marginal (<1% of luminal concentration), were mainly as intact glucoside or as aglycon for TαG and TßG, respectively. Addition of both inhibitors significantly increased the amount of intact glucosides retrieved from the mucosal tissues as compared to controls. In conclusion, bacterial hydrolysis was identified as the most important source of TßG loss, whereas TαG seemed less prone to degradation or absorption in these in vitro and ex vivo models.


Assuntos
Jejuno , Timol , Animais , Bactérias , Mucosa Intestinal , Intestino Delgado , Suínos
5.
Poult Sci ; 99(9): 4442-4453, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32867988

RESUMO

It was hypothesized that dietary guanidinoacetic acid (GAA), the precursor of creatine (Cr), would be beneficial to heat-stressed finisher broilers owing to improved cellular energy status and arginine sparing effects. A total of 720 one-day-old male Ross 308 broilers were allocated to 3 treatments, 0 (control), 0.6, or 1.2 g/kg of GAA added to complete corn-soybean meal diets, and were fed for 39 D, with 12 replicates (20 birds each) per treatment. A chronic cyclic heat stress model (at a temperature of 34°C and 50 to 60% relative humidity for 7 h daily) was applied in the finisher phase (day 25-39). Samples were taken on day 26 and 39 to determine thrombocyte, white blood cell, corticosterone, protein and amino acid levels in blood and Cr, phosphocreatine (PCr), and adenosine triphosphate levels in the breast muscle. Meat quality was assessed on day 40 after overnight fasting. Guanidinoacetic acid at a dose of 1.2 g/kg decreased feed-to-gain ratio compared with the control in the grower phase (1.32 vs. 1.35, respectively; P <0.05). In the finisher period, the supplementation of 1.2 g/kg of GAA reduced feed intake compared with the control (-3.3%, P <0.05), whereas both GAA supplementation levels improved feed efficiency markedly (1.76, 1.66, and 1.67 for 0 [control], 0.6, and 1.2 g/kg of GAA, respectively, P <0.05). Mortality outcomes highlight that GAA feeding improved survival during heat stress, supported by lower panting frequency (linear effect, P <0.05). Plasma arginine was higher with increase in dietary GAA concentration on day 26 (+18.3 and + 30.8% for 0.6 and 1.2 g/kg of GAA, respectively; P <0.05). This suggests enhanced availability of arginine for other metabolic purposes than de novo GAA formation. In the breast muscle, PCr (day 39, P <0.05), free Cr (day 39, P <0.05), total Cr (both days, P <0.05), and PCr-to-adenosine triphosphate ratio (day 39, P <0.05) levels were increased with higher GAA content in diet. Guanidinoacetic acid supplementation improved feed conversion and survival during chronic cyclic heat stress, which may be associated with enhanced breast muscle energy status and arginine sparing effect.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas , Suplementos Nutricionais , Metabolismo Energético , Glicina/análogos & derivados , Resposta ao Choque Térmico , Ração Animal , Animais , Arginina/metabolismo , Creatina/metabolismo , Dieta/veterinária , Metabolismo Energético/efeitos dos fármacos , Glicina/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Masculino
6.
Br Poult Sci ; 60(5): 554-563, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31190558

RESUMO

1. Guanidinoacetic acid (GAA) is the single endogenous precursor of creatine, which plays a critical role in energy homeostasis of cells. Since GAA is endogenously converted to creatine by methylation, it was hypothesised that the effects of dietary GAA supplementation might determine the methionine (Met) availability in corn-soybean based diets. 2. A total of 540, one-day-old male Ross 308 broilers were allocated to nine dietary treatments with six replicates (10 birds each) in a 3 × 3 factorial arrangement with three graded levels of supplementary Met (+0.4 g/kg per level), whilst cystine was equal across groups, resulting in a low, medium and high level of total sulphur amino acids, and with three levels of GAA (0, 0.6 and 1.2 g/kg). Birds were fed for 42 days. 3. Increasing levels of supplemental Met enhanced performance indices in all rearing periods, although there was no effect on feed conversion ratio in the grower or feed intake in the finisher periods. Final body weight was 8.8% and 14.6% higher in the birds fed medium and high Met diets, respectively, compared to the low Met level. Relative breast weight and protein content in muscle on d 25 linearly increased with higher levels of Met. At low and high Met levels, growth in the finisher phase was negatively affected by supplementing GAA at 1.2 g/kg. It was suggested that disturbances in methylation homeostasis and/or changes in Arg metabolism might explain these findings. At the end of the grower phase, muscle creatine content was higher when feeding GAA at 0.6 and 1.2 g/kg (4464 and 4472, respectively, vs. 4054 mg/kg fresh muscle in the control group). 4. The effects of dietary GAA supplementation were influenced by the dietary Met level only in the finisher period, which indicates the need for proper sulphur amino acid formulation in diets when feeding GAA.


Assuntos
Galinhas/fisiologia , Glicina/análogos & derivados , Metionina/metabolismo , Músculos Peitorais/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Disponibilidade Biológica , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Metabolismo Energético/efeitos dos fármacos , Glicina/administração & dosagem , Glicina/metabolismo , Masculino , Metionina/administração & dosagem , Tamanho do Órgão/efeitos dos fármacos , Músculos Peitorais/efeitos dos fármacos , Distribuição Aleatória
7.
Animal ; 13(8): 1641-1650, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30458891

RESUMO

Glutathione (GSH) is considered to play an important role in maintaining the integrity of the small intestine. In piglets, altered mucosal GSH levels might therefore be involved in weaning-induced changes of the small intestinal morphology and barrier function. To test this hypothesis, we aimed to challenge the mucosal GSH redox status during the first 28 days after weaning, by feeding diets containing 5% fresh linseed oil (CON), or 2.5% (OF1) or 5% (OF2) peroxidized linseed oil (peroxide value 225 mEq O2/kg oil) and exploring the effects on gut integrity. Piglets were pair-fed and had a total daily feed allowance of 32 g/kg BW. A fourth treatment included animals that were fed the control diet ad libitum (ACON). Animals were sampled at days 5 and 28 post-weaning. The malondialdehyde (MDA) concentration and GSH redox status (GSH/GSSG Eh) were determined in blood, liver and small intestinal mucosa. Histomorphology of the duodenal and jejunal mucosa was determined, and Ussing chambers were used to assess fluorescein isothiocyanate dextran (FD4) and horseradish peroxidase (HRP) fluxes across the mucosa. Results show that peroxidized linseed oil imposed an oxidative challenge at day 28, but not at day 5 post-weaning. At day 28, increasing levels of dietary peroxides to pair-fed pigs linearly increased MDA levels in duodenal and jejunal mucosa. Moreover, FD4 fluxes were significantly increased in OF1 (+75%) and OF2 (+64%) in the duodenum, and HRP fluxes tended (P=0.099) to show similar differences, as compared to CON. This co-occurred with a significant 11 mV increase of the hepatic GSH/GSSG Eh, potentiated by a significantly increased GSH peroxidase activity for treatments OF1 (+47%) and OF2 (+63%) in liver as compared to CON. Furthermore; duodenal HRP flux significantly correlated with the hepatic glutathione disulphide (GSSG) level (r=0.650), as also observed in the jejunum for hepatic GSSG (r=0.627) and GSH/GSSG Eh (r=0.547). The jejunal permeability was not affected, but FD4 and HRP fluxes significantly correlated with the local GSH (r=0.619; r=0.733) and GSSG (r=0.635; r=0586) levels. Small intestinal histomorphology was not affected by dietary lipid peroxides, nor were there any correlations found with the GSH redox system. To conclude, under oxidative stress conditions, jejunal barrier function is related to the local and hepatic GSH redox system. It is suggested that the hepatic GSH system participates in the elimination of luminal peroxides, and thereby impacts on duodenal barrier function.


Assuntos
Glutationa/metabolismo , Intestino Delgado/efeitos dos fármacos , Óleo de Semente do Linho/farmacologia , Suínos/metabolismo , Ração Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Dissulfeto de Glutationa/metabolismo , Intestino Delgado/metabolismo , Intestino Delgado/fisiologia , Óleo de Semente do Linho/administração & dosagem , Óleo de Semente do Linho/química , Malondialdeído/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Desmame
8.
Br Poult Sci ; 59(4): 443-451, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29756995

RESUMO

(1) Guanidinoacetic acid (GAA) is the single immediate endogenous precursor of creatine (Cr). It was hypothesised that dietary GAA would have different effects on performance and energy metabolites in breast muscle depending on the nutrient density (ND) of corn-soybean-based diets. (2) A total of 540 one-day-old male Ross 308 broilers were allocated to 9 dietary treatments with 6 replicates (10 birds each) in a 3 × 3 factorial arrangement with three levels of ND (low, 2800; medium, 2950 and high, 3100 kcal metabolizable energy (ME)/kg; and with the other nutrients being constant relative to ME) and supplemented with three levels of GAA (0, 0.6 and 1.2 g/kg) in a 42-d feeding trial. (3) In the starter and grower periods, increasing levels of ND improved body weight (BW), average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR), with the exception of ADFI in the starter period. GAA supplementation did not affect performance characteristics. All performance indicators responded markedly to increasing ND in the finisher period, whereas the highest GAA level reduced ADFI compared to the unsupplemented control (156 vs. 162 g/d) and concomitantly FCR (1.81 vs. 1.93). No interactive effects were noted for any performance trait. The high ND diet resulted in more breast meat yield on d42, associated with higher fat content and darker colour compared to the other ND levels. The GAA supplementation did not affect carcass and breast traits. At the end of the experiment, Cr was elevated when feeding GAA at 1.2 g/kg (5455 vs. 4338 mg/kg fresh muscle). (4) To conclude, ND had a substantial effect on performance and carcass traits, whereas any effect of GAA was limited to FCR in the finisher period and independent of diet ND level.


Assuntos
Galinhas/fisiologia , Metabolismo Energético/efeitos dos fármacos , Glicina/análogos & derivados , Músculos Peitorais/efeitos dos fármacos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Glicina/administração & dosagem , Glicina/metabolismo , Masculino , Músculos Peitorais/fisiologia , Distribuição Aleatória , Glycine max/química , Zea mays/química
9.
J Thromb Haemost ; 16(7): 1268-1277, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29742318

RESUMO

Essentials Von Willebrand ristocetin cofactor activity (VWF:RCo) is not a completely reliable assay. Three automated VWF activity assays were compared within a von Willebrand disease (VWD) cohort. Raw values for all three assays were virtually the same. An overall problem within type 2A/IIE VWD using VWF:GPIb-binding activity/VWF:Ag was observed. SUMMARY: Background von Willebrand disease (VWD) is an inherited bleeding disorder caused by quantitative (type 1 and 3) or qualitative (type 2) von Willebrand factor (VWF) defect. VWD diagnosis and classification require numerous laboratory tests. VWF: glycoprotein Ib (GPIb)-binding activity assays are used to distinguish type 1 from type 2 VWD. Objectives Three different automated VWF:GPIb-binding activity assays were compared. Patients and methods BC-VWF:RCo (Siemens Healthcare Diagnostics), HemosIL® VWF:RCo (Instrumentation Laboratory) and INNOVANCE® VWF:Ac (Siemens Healthcare Diagnostics) were performed in a well typed VWD cohort (n = 142). Results Based on the three most used VWD parameters (FVIII:C, VWF:Ag and VWF:GPIb-binding activity) and using a cut-off of <0.70 for type 2 VWD revealed sensitivity and specificity of, respectively, 92% and 72.4% for VWF:RCo/VWF:Ag, 84% and 89.7% for VWF:GPIbR/VWF:Ag, and 92% and 85.1% for VWF:GPIbM/VWF:Ag, whereas a lowered cut-off of < 0.60 resulted in reduced sensitivity with increased specificity for all assays. Conclusion VWD classification based on FVIII:C, VWF:Ag and VWF:GPIb-binding activity revealed an overall problem with normal VWF:GPIb-binding activity/VWF:Ag within type 2, especially type 2A/IIE. Although all assays were practically identical, BC-VWF:RCo had higher %CV compared with both new assays but comparable lower limit of quantification (LLOQ) ~4 IU dL-1 . No clear improved distinction between type 1 and 2 VWD with new assays was seen. BC-VWF: RCo and HemosIL® are ristocetin dependent, whereas INNOVANCE® does not rely upon ristocetin and is not influenced by VWF polymorphisms increasing VWF:GPIb-binding activity levels. INNOVANCE® seems to be the best choice as a first-line VWF:GPIb-binding activity assay, providing the best balance between sensitivity and specificity for type 2 VWD.


Assuntos
Testes Hematológicos/métodos , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Doenças de von Willebrand/diagnóstico , Fator de von Willebrand/metabolismo , Automação Laboratorial , Bélgica , Biomarcadores/sangue , Estudos Transversais , República Tcheca , Desenho de Equipamento , Testes Hematológicos/instrumentação , Humanos , Valor Preditivo dos Testes , Ligação Proteica , Reprodutibilidade dos Testes , Doenças de von Willebrand/sangue , Doenças de von Willebrand/classificação
10.
Artigo em Inglês | MEDLINE | ID: mdl-28975689

RESUMO

BACKGROUND: Currently, there are no histological criteria to diagnose irritable bowel syndrome (IBS). Our aims were (i) to examine the distribution of inflammatory cells in the colon of healthy and IBS subjects and (ii) to find histological diagnosis criteria for IBS. METHODS: Colonic biopsies were taken from four distinct regions of the colon from 20 controls (HC) and 11 patients with IBS (4 with constipation (IBS-C) and 7 with diarrhea (IBS-D) and embedded in paraffin. Macrophages, mast cells, eosinophils, and T lymphocytes were immunostained and positive cells counted. KEY RESULTS: In both HC and IBS patients, global cellularity decreased from the cecum to the rectum (P < .01) which is attributed to reduced number of macrophages (P < .05) and eosinophils (P < .001) but not T cells. Mast cells were reduced in IBS (P < .05) but not in HC, particularly in IBS-D (P < .05). Results showed higher number of macrophages in the left colon of IBS subjects than HC (P < .05). CONCLUSION & INFERENCES: Here we report a decreasing gradient of immune cells from the cecum to the rectum of the human colon. Although global cellularity cannot be used to distinguish between IBS and HC, closer analysis of macrophages and mast cells may be useful markers to confirm IBS histologically and to differentiate between IBS-C and IBS-D when clinical presentation alternates between constipation and diarrhoea. This pilot study remains to be confirmed with greater number of patients.


Assuntos
Colo/imunologia , Inflamação/imunologia , Mucosa Intestinal/imunologia , Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/imunologia , Idoso , Biópsia , Colo/patologia , Eosinófilos/patologia , Feminino , Humanos , Inflamação/complicações , Inflamação/patologia , Mucosa Intestinal/patologia , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/patologia , Macrófagos/patologia , Masculino , Mastócitos/patologia , Pessoa de Meia-Idade , Projetos Piloto , Linfócitos T/patologia
11.
Eur Cell Mater ; 33: 13-27, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28076651

RESUMO

Roughened surfaces are increasingly being used for dental implant applications as the enlarged contact area improves bone cell anchorage, thereby facilitating osseointegration. However, the additional surface area also entails a higher risk for the development of biofilm associated infections, an etiologic factor for many dental ailments, including peri-implantitis. To overcome this problem, we designed a dental implant composed of a porous titanium-silica (Ti/SiO2) composite material and containing an internal reservoir that can be loaded with antimicrobial compounds. The composite material consists of a sol-gel derived mesoporous SiO2 diffusion barrier integrated in a macroporous Ti load-bearing structure obtained by powder metallurgical processing. The antimicrobial compounds can diffuse through the porous implant walls, thereby reducing microbial biofilm formation on the implant surface. A continuous release of µM concentrations of chlorhexidine through the Ti/SiO2 composite material was measured, without initial burst effect, over at least 10 days and using a 5 mM chlorhexidine solution in the implant reservoir. Metabolic staining, CFU counting and visualisation by scanning electron microscopy confirmed that Streptococcus mutans biofilm formation on the implant surface was almost completely prevented due to chlorhexidine release (preventive setup). Moreover, we demonstrated efficacy of released chlorhexidine against mature Streptococcus mutans biofilms (curative setup). In conclusion, we provide a proof of concept of the sustained release of chlorhexidine, one of the most widely used oral antiseptics, through the Ti/SiO2 material thereby preventing and eradicating biofilm formation on the surface of the dental implant. In principle, our flexible design allows for the use of any bioactive compound, as discussed.


Assuntos
Biofilmes/crescimento & desenvolvimento , Clorexidina/administração & dosagem , Clorexidina/farmacologia , Implantes Dentários , Dióxido de Silício/química , Streptococcus mutans/fisiologia , Titânio/farmacologia , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Preparações de Ação Retardada , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Porosidade , Desenho de Prótese , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/metabolismo , Streptococcus mutans/ultraestrutura
12.
Neuropathol Appl Neurobiol ; 43(5): 433-449, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27732747

RESUMO

AIMS: Bi-allelic inactivation of SWI/SNF related, matrix-associated, actin-dependent regulator of chromatin, subfamily B member 1 (SMARCB1; also known as INI1) and loss of immunohistochemical expression of SMARCB1 define the group of SMARCB1-deficient tumours. Initially highlighted in malignant rhabdoid tumours, this inactivation has subsequently been observed in several intra and extracranial tumours. To date, primary meningeal SMARCB1-deficient tumours have not been described. We report two cases of meningeal SMARCB1-deficient tumours occurring in adults. METHODS: We performed immunohistochemical analyses, comparative genomic hybridization, fluorescence in situ hybridization and targeted next-generation sequencing. RESULTS: The first meningeal tumour was a solitary mass, composed of rhabdoid, adenoid, chordoid and sarcomatoid areas. The second case presented as multiple, bilateral, supra and infratentorial nodules, was composed of fusiform and ovoid cells embedded in a myxoid stroma. Tumour cells were positive for epithelial membrane antigen (EMA), vimentin and CD34 and negative for SMARCB1 and meningothelial, melanocytic, muscular, glial markers. In the first case, one allele of SMARCB1 was completely deleted, whereas in the second case, loss of expression of SMARCB1 was observed as a consequence of a homozygous deletion of SMARCB1. CONCLUSIONS: The phenotype and genotype of these two cases did not fit diagnostically with entities already known to be SMARCB1-deficient tumours. As both tumours shared common features, they are regarded as belonging to an emerging group of primary meningeal SMARCB1-deficient tumours, not described to date. To facilitate the identification and characterization of these tumours, we recommend SMARCB1 immunohistochemistry for primary meningeal tumours which are difficult to classify, especially if immunopositive for EMA and CD34.


Assuntos
Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patologia , Proteína SMARCB1/genética , Adulto , Humanos , Masculino
13.
J Anim Sci ; 94(10): 4188-4195, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27898857

RESUMO

Vitamin E is important for animal production because of its effects on health and product quality, but the amount and form required remains controversial. Our objective was to quantify the absolute bioavailability of oral -α-tocopheryl acetate (α-TAc) in swine (22 ± 1 kg and 8 wk old, fitted with jugular catheters) adapted to a diet supplemented with 75 mg/kg -α-TAc; 75 mg/kg was chosen because this level represents the nonweighted average inclusion level in piglet diets across Western key swine-producing countries. For this, a 350-g test meal (6% fat) was supplied at time 0 containing 75 mg deuterated (D9) -α-TAc to 9 animals, and 8 animals received an intravenous () dose containing deuterated (D6) RRR-α-tocopherol (α-T) at one-eighth the oral dose and a test meal without supplemental vitamin E. Plasma samples (12 to 13 per animal) were obtained at incremental intervals over 75 h for analysis of deuterated α-T using liquid chromatography-tandem mass spectrometry. Surprisingly, the i.v. dose rapidly disappeared from plasma and then reappeared. The half-life for this first peak was only 1.7 ± 0.3 min. The second peak had an appearance rate (Ka) of 0.10 ± 0.06 d and a half-life of 5.9 ± 1.2 h. Oral dosing resulted, after a lag of 56 min, in a Ka of 0.91 ± 0.21 d and a half-life of 2.6 ± 0.8 h. The bioavailability for oral α-TAc was 12.5%, whereas the area under the curve was only 5.4%. This low bioavailability, small area under the curve, and short half-life are likely because of various factors, that is, the use of only 6% fat in the diet, the use of the acetate ester and , and the high dose relative to requirements. In conclusion, i.v. dosed vitamin E shows both a rapid and a very slow pool, whereas orally dosed vitamin E shows a single slow pool. The oral material has a very short half-live (44% of i.v. or 2.6 h), low bioavailability (12.5%), and a very small area under the curve (5.4%), bringing into question the efficacy of typical doses of vitamin E in swine diets for alleviating oxidative stress.


Assuntos
Suínos/fisiologia , Vitamina E/farmacocinética , alfa-Tocoferol/farmacocinética , Animais , Área Sob a Curva , Disponibilidade Biológica , Deutério , Dieta , Suplementos Nutricionais , Meia-Vida , Vitamina E/sangue , Vitaminas/sangue , Vitaminas/farmacocinética , alfa-Tocoferol/sangue
14.
Cytopathology ; 27(5): 359-68, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27146425

RESUMO

OBJECTIVE: Since the guidelines of the International Committee for Standardisation in Haematology (ICSH) in 1984 and those of the European Committee for External Quality Assessment Programmes in Laboratory Medicine (EQALM) in 2004, no leading organisation has published technical recommendations for the preparation of air-dried cytological specimens using May-Grünwald-Giemsa (MGG) staining. DATA SOURCES: Literature data were retrieved using reference books, baseline-published studies, articles extracted from PubMed/Medline and Google Scholar, and online-available industry datasheets. RATIONALE: The present review addresses all pre-analytical issues concerning the use of Romanowsky's stains (including MGG) in haematology and non-gynaecological cytopathology. It aims at serving as actualised, best practice recommendations for the proper handling of air-dried cytological specimens. It, therefore, appears complementary to the staining criteria of the non-gynaecological diagnostic cytology handbook edited by the United Kingdom National External Quality Assessment Service (UK-NEQAS) in February 2015.


Assuntos
Citodiagnóstico , Hematologia/métodos , Coloração e Rotulagem , Amarelo de Eosina-(YS)/química , França , Guias como Assunto , Hematologia/normas , Humanos , Azul de Metileno/química , Garantia da Qualidade dos Cuidados de Saúde , Reino Unido
15.
J Food Prot ; 79(1): 51-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26735029

RESUMO

This study builds on the results of a previous study in which six commercial feed products based on organic acids were evaluated with respect to Salmonella contamination of piglets in an artificially challenged seeder model. In the present study, the efficacy of three of these commercial products was assessed for Salmonella reduction in fattening pigs on one closed farm with a natural high Salmonella prevalence. In each of four fattening compartments, one of the following feed treatments was evaluated during two consecutive fattening rounds: (i) butyric acid (active ingredients at 1.3 kg/ton of feed; supplement A1), (ii) a combination of short-chain organic acids (mixture of free acids and salts) and natural extracts (2.92 kg/ton; supplement A4), (iii) a 1:1 blend of two commercial products consisting of medium-chain fatty acids, lactic acid, and oregano oil (3.71 kg/ton; supplement A5+A6), and (iv) a control feed. On the farm, the Salmonella status of the fattening pigs was evaluated by taking fecal samples twice during the fattening period. At the slaughterhouse, samples were collected from the cecal contents and the ileocecal lymph nodes. Salmonella isolates were serotyped and characterized by pulsed-field gel electrophoresis. This farm had a particularly high number of pigs shedding Salmonella with a wide variety of sero- and pulsotypes. Only the feed blend based on the medium-chain fatty acids was able to significantly reduce Salmonella prevalence both on the farm and at the slaughterhouse. With this combined supplement, the Salmonella reduction in the feces at slaughter age, in cecal contents at slaughter, and the lymph nodes was 50, 36, and 67%, respectively, compared with the control animals. This promising finding calls for further investigation including cost-efficiency of this combined feed product and its effect on the animals.


Assuntos
Ácidos Graxos/metabolismo , Salmonelose Animal/microbiologia , Salmonella/fisiologia , Doenças dos Suínos/microbiologia , Matadouros , Animais , Ceco/microbiologia , Suplementos Nutricionais/análise , Eletroforese em Gel de Campo Pulsado , Fezes/microbiologia , Prevalência , Salmonella/genética , Salmonella/isolamento & purificação , Salmonelose Animal/epidemiologia , Salmonelose Animal/metabolismo , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/metabolismo
17.
Ann Oncol ; 27(2): 306-14, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26598546

RESUMO

BACKGROUND: ALK-negative anaplastic large cell lymphoma associated with breast implant (i-ALCL) has been recently recognized as a distinct entity. Among 43 830 lymphomas registered in the French Lymphopath network since 2010, 300 breast lymphomas comprising 25 peripheral T-cell lymphomas (PTCL) were reviewed. Among PTCL, ALK-negative ALCL was the most frequent and all of them were associated with breast implants. PATIENTS AND METHODS: Since 2010, all i-ALCL cases were collected from different institutions through Lymphopath. Immuno-morphologic features, molecular data and clinical outcome of 19 i-ALCLs have been retrospectively analyzed. RESULTS: The median age of the patients was 61 years and the median length between breast implant and i-ALCL was 9 years. Most implants were silicone-filled and textured. Implant removal was performed in 17 out of 19 patients with additional treatment based on mostly CHOP or CHOP-like chemotherapy regimens (n = 10/19) or irradiation (n = 1/19). CHOP alone or ABVD following radiation without implant removal have been given in two patients. The two clinical presentations, i.e. effusion and less frequently tumor mass correlated with distinct histopathologic features: in situ i-ALCL (anaplastic cell proliferation confined to the fibrous capsule) and infiltrative i-ALCL (pleomorphic cells massively infiltrating adjacent tissue with eosinophils and sometimes Reed-Sternberg-like cells mimicking Hodgkin lymphoma). Malignant cells were CD30-positive, showed a variable staining for EMA and were ALK negative. Most cases had a cytotoxic T-cell immunophenotype with variable T-cell antigen loss and pSTAT3 nuclear expression. T-cell receptor genes were clonally rearranged in 13 out of 13 tested cases. After 18 months of median follow-up, the 2-year overall survival for in situ and infiltrative i-ALCL was 100% and 52.5%, respectively. CONCLUSIONS: In situ i-ALCLs have an indolent clinical course and generally remain free of disease after implant removal. However, infiltrative i-ALCLs could have a more aggressive clinical course that might require additional therapy to implant removal.


Assuntos
Implantes de Mama/efeitos adversos , Linfoma Anaplásico de Células Grandes/patologia , Linfoma de Células T Periférico/patologia , Silicones/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Feminino , Doença de Hodgkin/patologia , Humanos , Imunofenotipagem , Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/induzido quimicamente , Linfoma Anaplásico de Células Grandes/mortalidade , Linfoma de Células T Periférico/induzido quimicamente , Linfoma de Células T Periférico/mortalidade , Pessoa de Meia-Idade , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Estudos Retrospectivos , Fator de Transcrição STAT3/metabolismo , Linfócitos T Citotóxicos/imunologia
18.
Int J Surg Pathol ; 24(4): 353-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26657576

RESUMO

Xanthomas are common in cutaneous sites but may also be seen in unusual locations. In view of the paucity of reported cases, the occurrence of such lesions within the breast stroma would appear to be either unusual, underreported, or ignored. Indeed, most reports of the few breast xanthomas and of the even fewer xanthomatous fibroadenomas reported have appeared in the older literature. Herein, a case of fibroadenoma with multiple foci of xanthoma is reported, the literature is briefly reviewed, and the apparent difference between the previous cases and the current case is highlighted.


Assuntos
Neoplasias da Mama/patologia , Fibroadenoma/patologia , Neoplasias da Mama/diagnóstico , Feminino , Fibroadenoma/diagnóstico , Humanos , Pessoa de Meia-Idade , Xantomatose/patologia
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