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1.
Materials (Basel) ; 15(11)2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35683290

RESUMO

In the animal kingdom, continuously erupting incisors provided an attractive model for studying the enamel matrix and mineral composition of teeth during development. Enamel, the hardest mineral tissue in the vertebrates, is a tissue sensitive to external conditions, reflecting various disturbances in its structure. The developing dental enamel was monitored in a series of incisor samples extending the first four weeks of postnatal life in the spiny mouse. The age-dependent changes in enamel surface morphology in the micrometre and nanometre-scale and a qualitative assessment of its mechanical features were examined by applying scanning electron microscopy (SEM) and atomic force microscopy (AFM). At the same time, structural studies using XRD and vibrational spectroscopy made it possible to assess crystallinity and carbonate content in enamel mineral composition. Finally, a model for predicting the maturation based on chemical composition and structural factors was constructed using artificial neural networks (ANNs). The research presented here can extend the existing knowledge by proposing a pattern of enamel development that could be used as a comparative material in environmental, nutritional, and pharmaceutical research.

2.
J Clin Med ; 11(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35566566

RESUMO

Our study aimed to evaluate the effect of whole body vibration (WBV) treatment as an non-pharmacological method of treatment for early osteopenia in ovariectomized female rats. In total, 48 female Wistar rats were assigned to two groups: sham-operated control (SHAM, n = 12) and ovariectomized (n = 36). Four weeks after ovariectomy, the animals were divided into three experimental groups (n = 12 each): ovariectomized (OVX), ovariectomized subjected to whole body vibration with acceleration level of 0.3 g (OVX + WBV), or ovariectomized subjected to i.m. injection of Zoledronic acid at a dose of 0.025 mg/kg (OVX + ZOL). After the 8th and 16th week of treatment n = 6 rats from each group were euthanized and isolated femora were subjected to histological examination of trabecular bone and analysis of the expression of collagen 1 (Col1), osteoprotegerin (OPG), and receptor activator of nuclear factor kappa-Β ligand (RANKL) involved in bone turnover. The obtained results indicated that widespread vibration therapy can provide negative outcomes such as deterioration of trabecular bone histomorphometry.

3.
Sensors (Basel) ; 22(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35009863

RESUMO

The presented paper introduces principal component analysis application for dimensionality reduction of variables describing speech signal and applicability of obtained results for the disturbed and fluent speech recognition process. A set of fluent speech signals and three speech disturbances-blocks before words starting with plosives, syllable repetitions, and sound-initial prolongations-was transformed using principal component analysis. The result was a model containing four principal components describing analysed utterances. Distances between standardised original variables and elements of the observation matrix in a new system of coordinates were calculated and then applied in the recognition process. As a classifying algorithm, the multilayer perceptron network was used. Achieved results were compared with outcomes from previous experiments where speech samples were parameterised with the Kohonen network application. The classifying network achieved overall accuracy at 76% (from 50% to 91%, depending on the dysfluency type).


Assuntos
Percepção da Fala , Gagueira , Humanos , Redes Neurais de Computação , Análise de Componente Principal , Fala
4.
Int J Mol Sci ; 22(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34948030

RESUMO

The current study examined the effects of exposure of pregnant dams to fumonisins (FBs; FB1 and FB2), from the seventh day of pregnancy to parturition, on offspring bone metabolism and properties. The rats were randomly divided into three groups intoxicated with FBs at either 0, 60, or 90 mg/kg b.w. Body weight and bone length were affected by fumonisin exposure, irrespective of sex or dose, while the negative and harmful effects of maternal FBs' exposure on bone mechanical resistance were sex and dose dependent. The immunolocalization of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-Β ligand (RANKL), in bone and articular cartilage, indicated that the observed bone effects resulted from the FB-induced alterations in bone metabolism, which were confirmed by the changes observed in the Western blot expression of OPG and RANKL. It was concluded that the negative effects of prenatal FB exposure on the general growth and morphometry of the offspring bones, as a result of the altered expression of proteins responsible for bone metabolism, were dose and sex dependent.


Assuntos
Osso Esponjoso/metabolismo , Fumonisinas/toxicidade , Osteoprotegerina/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ligante RANK/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Osso Esponjoso/efeitos dos fármacos , Cartilagem Articular/metabolismo , Relação Dose-Resposta a Droga , Feminino , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Caracteres Sexuais
5.
Int J Mol Sci ; 22(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34830409

RESUMO

Fumonisins are protein serine/threonine phosphatase inhibitors and potent inhibitors of sphingosine N-acyltransferase (ceramide synthase) disrupting de novo sphingolipid biosynthesis. The experiment was conducted to evaluate the effects of fumonisins (FB) exposure from the 7th day of pregnancy to parturition on offspring bone development. The rats were randomly allocated to either a control group (n = 6), not treated with FBs, or to one of the two groups intoxicated with FBs (either at 60 mg FB/kg b.w. or at 90 mg FB/kg b.w. Numerous negative, offspring sex-dependent effects of maternal FB exposure were observed with regards to the histomorphometry of trabecular bone. These effects were due to FB-inducted alterations in bone metabolism, as indicated by changes in the expression of selected proteins involved in bone development: tissue inhibitor of metalloproteinases 2 (TIMP-2), matrix metalloproteinase 8 (MMP-8), matrix metalloproteinase 13 (MMP-13), and vascular endothelial growth factor (VEGF). The immunolocalization of MMPs and TIMP-2 was performed in trabecular and compact bone, as well as articular and growth plate cartilages. Based on the results, it can be concluded that the exposure of pregnant dams to FB negatively affected the expression of certain proteins responsible for bone matrix degradation in newborns prenatally exposed to FB in a dose- and sex-dependent manner.


Assuntos
Fumonisinas/farmacologia , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 8 da Matriz/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Animais Recém-Nascidos , Desenvolvimento Ósseo/genética , Osso Esponjoso/efeitos dos fármacos , Osso Esponjoso/crescimento & desenvolvimento , Cartilagem/crescimento & desenvolvimento , Cartilagem/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Lâmina de Crescimento/efeitos dos fármacos , Oxirredutases/antagonistas & inibidores , Oxirredutases/genética , Gravidez , Ratos , Esfingolipídeos/biossíntese
6.
Int J Mol Sci ; 22(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34502096

RESUMO

The potential of Fourier Transform infrared microspectroscopy (FTIR microspectroscopy) and multivariate analyses were applied for the classification of the frequency ranges responsible for the distribution changes of the main components of articular cartilage (AC) that occur during dietary ß-hydroxy-ß-methyl butyrate (HMB) supplementation. The FTIR imaging analysis of histological AC sections originating from 35-day old male piglets showed the change in the collagen and proteoglycan contents of the HMB-supplemented group compared to the control. The relative amount of collagen content in the superficial zone increased by more than 23% and in the middle zone by about 17%, while no changes in the deep zone were observed compared to the control group. Considering proteoglycans content, a significant increase was registered in the middle and deep zones, respectively; 62% and 52% compared to the control. AFM nanoindentation measurements collected from animals administered with HMB displayed an increase in AC tissue stiffness by detecting a higher value of Young's modulus in all investigated AC zones. We demonstrated that principal component analysis and artificial neural networks could be trained with spectral information to distinguish AC histological sections and the group under study accurately. This work may support the use and effectiveness of FTIR imaging combined with multivariate analyses as a quantitative alternative to traditional collagenous tissue-related histology.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Valeratos/farmacologia , Animais , Cartilagem Articular/química , Cartilagem Articular/metabolismo , Colágeno/metabolismo , Suplementos Nutricionais , Módulo de Elasticidade , Masculino , Redes Neurais de Computação , Análise de Componente Principal , Proteoglicanas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos , Valeratos/administração & dosagem
7.
Toxins (Basel) ; 13(6)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070555

RESUMO

Fumonisins (FB) are metabolites found in cereal grains (including maize), crop products, and pelleted feed. There is a dearth of information concerning the effects of FB intoxication on the intestinal histomorphometry, the expression of intestinal tight junction proteins, and the bone structure and liver in pre-laying hens. The current experiment was carried out on hens from the 11th to the 14th week of age. The hens were orally administered an extract containing fumonisin B1 (FB1) and fumonisin B2 (FB2) at doses of 0.0 mg/kg b.w. (body weight), 1.0 mg/kg b.w., 4.0 mg/kg b.w., and 10.9 mg/kg b.w. for 21 days. Following FB intoxication, the epithelial integrity of the duodenum and jejunum was disrupted, and dose-dependent degenerative changes were observed in liver. An increased content of immature collagen was observed in the bone tissue of FB-intoxicated birds, indicating intensified bone turnover. A similar effect was observed with regards to the articular cartilage, where enhanced fibrillogenesis was observed mainly in the group of birds that received the FB extract at a dose of 10.9 mg/kg b.w. In conclusion, FB intoxication resulted in negative structural changes in the bone tissue of the hens, which could result in worsened bone mechanics and an increase in the risk of bone fractures. Fumonisin administration, even at a dose of 1.0 mg/kg b.w., can lead to degradation of the intestinal barrier and predispose hens to intestinal disturbances later in life.


Assuntos
Osso e Ossos/efeitos dos fármacos , Fumonisinas/intoxicação , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proteínas de Junções Íntimas/análise , Administração Oral , Animais , Osso e Ossos/patologia , Galinhas , Feminino , Intestinos/química , Intestinos/patologia , Fígado/patologia
8.
Animals (Basel) ; 10(12)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348724

RESUMO

The aim of the experiment was to assess the effect of dietary alpha-ketoglutarate (AKG) supplementation on performance, serum hormonal indices, duodenum and jejunum histomorphometry, meat quality characteristics, bone quality traits and cartilage degradation in laying hens with a mature skeletal system. Forty-eight 30 week-old Bovans Brown laying hens were randomly assigned to a control group or the group fed the basal diet plus 1.0% AKG. The experimental trial lasted 30 weeks. The supplementation of AKG increases blood serum content of leptin, ghrelin, bone alkaline phosphatate and receptor activator of nuclear factor kappa-Β ligand, while osteoprotegerin and osteocalcin decrease. While dietary AKG was given to laying hens negatively influenced villus length, crypt depth, villus/crypt ratio and absorptive surface area in duodenum and jejunum, these changes have no effect on feed intake, weight gain, nor laying performance. In breast muscles, no significant changes in skeletal muscle fatty acid composition were observed, however, a higher shear force and decreased cholesterol content following AKG supplementation were noted, showing the improvement of muscle quality. While dietary AKG supplementation did not affect the general geometric and mechanical properties of the tibia, it increased collagen synthesis and enhanced immature collagen content. In medullary bone, an increase of bone volume fraction, trabecular thickness, fractal dimension and decrease of trabecular space were observed in AKG supplemented group. The trabeculae in bone metaphysis were also significantly thicker after AKG supplementation. AKG promoted fibrillogenesis in articular cartilage, as indicated by increased cartilage oligomeric matrix protein immunoexpression. By improving the structure and maintaining the proper bone turnover rate of highly reactive and metabolically active medullar and trabecular bones AKG showed its anti-osteoporotic action in laying hens.

9.
Animals (Basel) ; 10(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142930

RESUMO

This study was conducted to examine the effect of dietary rye inclusion and xylanase supplementation on the bone quality of ISA Brown laying hens. Ninety-six laying hens were assigned to four groups: fed with wheat-corn diet or rye-wheat-corn diet (25% of hybrid rye inclusion) or nonsupplemented or supplemented with xylanase (200 mg/kg of feed) for a period of 25 weeks, from the 26th to the 50th week of age. X-ray absorptiometry, X-ray diffraction, and Fourier-transform infrared spectroscopy were used to provide comprehensive information about the structural organization of bone constitutive phases of the tibia mid-diaphysis in hens from all treatment groups. Bone hydroxyapatite size was not affected by diet. Xylanase supplementation influenced the carbonate-to-phosphate ratio and crystallinity index in hens fed with both diets. Xylanase had more pronounced effects on bone mineral density and collagen maturity in hens fed with the rye-wheat-corn diet versus those fed with the wheat-corn diet. The results of this study showed that modern rye varieties, when supplemented with exogenous xylanase, can be introduced to the diet of laying hens without any adverse effects on bone structure.

10.
Molecules ; 25(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143338

RESUMO

In this paper, stability of chlorophyll a monomers encapsulated into the Cremophor EL nano-micelles was studied under dark and moderate light conditions, typical of a room with natural or artificial lighting, in the presence of oxygen. The pigment stability against visible light was determined using the dynamic light scattering and molecular spectroscopy (UV-Vis absorption and stationary fluorescence) methods. Chlorophyll a, at the molar concentration of 10-5 M, was dissolved in the 5 wt% Cremophor emulsion for comparison in the ethanolic solution. The stability of such a self-assembly pigment-detergent nano-system is important in the light of its application on the commercial-scale. The presented results indicate the high stability of the pigment monomeric molecular organization in the nano-emulsion. During the storage in the dark, the half-lifetime was calculated as about 7 months. Additionally, based on the shape of absorption and fluorescence emission spectra, chlorophyll aggregation in the Cremophor EL aqueous solution along with the time was excluded. Moreover, the average size of detergent micelles as chlorophyll carriers was not affected after 70 days of the nano-system storage. Pigment stability against the moderate white light (0.1 mW) did not differ significantly from storage conditions in the dark. The photooxidation products, detected by occurrence of new absorption and fluorescence emission bands, was estimated on the negligible level. The stability of such a self-assembly pigment-detergent nano-system would potentially broaden the field of chlorophyll a (chl a) application in the food industry, medicine or artificial photosynthesis models.


Assuntos
Clorofila A/química , Glicerol/análogos & derivados , Micelas , Escuridão , Glicerol/química , Luz
11.
Biomolecules ; 10(5)2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32422985

RESUMO

Changes to the features of the enamel surface submitted to induced demineralisation and subsequent remineralisation were studied. The in vitro examination was conducted on polished slices of human molar teeth, divided in four groups: the untreated control (n = 20), challenged by a demineralisation with orthophosphoric acid (H3PO4) (n = 20), and challenged by a demineralisation following remineralisation with fluoride (F) varnish containing casein phosphopeptides (CPP) and amorphous calcium phosphate (ACP) compounds (n = 20). The specimens' enamel surfaces were subjected to analysis of structure, molecular arrangement, mechanical features, chemical composition, and crystalline organization of apatite crystals. Specimens treated with acid showed a significant decrease in crystallinity, calcium, and phosphorus levels as well as mechanical parameters, with an increase in enamel surface roughness and degree of carbonates when compared to the control group. Treatment with fluoride CPP-ACP varnish provided great improvements in enamel arrangement, as the destroyed hydroxyapatite structure was largely rebuilt and the resulting enamel surface was characterised by greater regularity, higher molecular and structural organisation, and a smoother surface compared to the demineralised one. In conclusion, this in vitro study showed that fluoride CPP-ACP varnish, by improving enamel hardness and initiating the deposition of a new crystal layer, can be an effective remineralising agent for the treatment of damaged enamel.


Assuntos
Caseínas/farmacologia , Esmalte Dentário/efeitos dos fármacos , Fluoretos Tópicos/farmacologia , Desmineralização do Dente/tratamento farmacológico , Caseínas/uso terapêutico , Esmalte Dentário/química , Esmalte Dentário/ultraestrutura , Fluoretos Tópicos/química , Fluoretos Tópicos/uso terapêutico , Humanos , Fenômenos Mecânicos , Dente Molar/química , Dente Molar/efeitos dos fármacos , Ácidos Fosfóricos/toxicidade , Desmineralização do Dente/etiologia
12.
PLoS One ; 14(12): e0226205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31809528

RESUMO

Kynurenic acid (KYNA) is a neuroactive metabolite of tryptophan. KYNA naturally occurs in breast milk and its content increases with lactation, indicating the role of neonatal nutrition in general growth with long-term health effects. KYNA is also an antagonist of ionotropic glutamate receptors expressed in bone cells. The aim of this study was to establish the effects of chronic KYNA supplementation on bone homeostasis in young rats, using mandible as a model bone. Female and male newborn Wistar rats were divided into control and KYNA-administered groups until 60 days of age (25x101 mg/L or 25x102 mg/L in drinking water). Hemimandibles were subjected to densitometry, computed tomography analysis and mechanical testing. Rats supplemented with KYNA at both doses showed a decrease in body weight. There were no effects of KYNA administration and mandible histomorphometry. In males, a significant quadratic effect (P < 0.001) was observed in the densitometry of the hemimandible, where BMD increased in the group supplemented with 2.5x101 mg/L of KYNA. Analysis of mechanical tests data showed that when fracture forces were corrected for bone geometry and rats body weight the improvement of bone material properties was observed in male and female rats supplemented with lower dose of KYNA. This study showed that chronic supplementation with KYNA may limit weight gain in the young, without adversely affecting the development of the skeleton.


Assuntos
Ácido Cinurênico/administração & dosagem , Mandíbula/fisiologia , Redução de Peso/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Fenômenos Biomecânicos/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Estudos de Casos e Controles , Suplementos Nutricionais , Feminino , Ácido Cinurênico/farmacologia , Masculino , Mandíbula/efeitos dos fármacos , Ratos , Ratos Wistar , Tomografia Computadorizada por Raios X
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117271, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31226619

RESUMO

Structural changes in the enamel surface subjected to induced demineralization and assessment of the influence of prenatal administration of ß-hydroxy ß-methylbutyrate (HMB) on enamel resistance were investigated. The examination was conducted on five sets of teeth from one-day-old spiny mice (Acomys cahirinus), one from the control and four from the experimental groups. Surface structure, molecular arrangement and crystalline organization of offspring's enamel both before and after etching were studied. Obtained results revealed that the physical and molecular arrangements of enamel were altered after the prenatal supplementation, and significantly affected its final structure and resistance against acid action. The enamel of incisors from the offspring which mothers were supplemented with HMB in a high dose (0.2 g/kgbw) and in the late period of gestation (26th-39th day) showed the highest endurance against acid treatment demonstrating only vestigial changes in their surface structure after acid action. Comparing to the remaining experimental groups, it was characterized by a reduced roughness and fractal dimension, significantly lower degree of demineralization and simultaneous lack of notable differences in the Raman spectra before and after acid etching. The results suggest that an increased enamel resiliency was the effect of a relatively high degree of mineralization and higher organization of the surface.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Valeratos/farmacologia , Ácidos/química , Animais , Animais Recém-Nascidos , Esmalte Dentário/embriologia , Esmalte Dentário/ultraestrutura , Suplementos Nutricionais , Feminino , Camundongos , Modelos Moleculares , Gravidez , Cuidado Pré-Natal , Propriedades de Superfície/efeitos dos fármacos , Valeratos/administração & dosagem
14.
PLoS One ; 14(4): e0215370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30978248

RESUMO

Alterations in the structure and mechanical properties of teeth in adult Wistar rats exposed to cadmium were investigated. Analyses were conducted on two sets of incisors from female and male specimens, that were intoxicated with cadmium (n = 12) or belonged to the control (n = 12). The cadmium group was administered with CdCl2 dissolved in drinking water with a dose of 4mg/kgbw for 10 weeks. The oral intake of cadmium by adult rats led to the range of structural changes in enamel morphology and its mechanical features. A significant increase of cadmium levels in the teeth in comparison to the control, a slight shift in the colour and reduction of pigmented enamel length, higher surface irregularity, a decrease of hydroxyapatite crystals size in the c-axis and simultaneous increase in pigmented enamel hardness were observed. The extent of these changes was sex-dependent and was more pronounced in males.


Assuntos
Cádmio/toxicidade , Incisivo/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Cádmio/administração & dosagem , Cádmio/farmacocinética , Cristalização , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Esmalte Dentário/fisiopatologia , Durapatita/química , Durapatita/metabolismo , Feminino , Dureza/efeitos dos fármacos , Incisivo/patologia , Incisivo/fisiopatologia , Masculino , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Minerais/metabolismo , Ratos , Ratos Wistar , Difração de Raios X
15.
J Anim Physiol Anim Nutr (Berl) ; 103(2): 626-643, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659706

RESUMO

It has been demonstrated in animal studies that prenatal administration of ß-hydroxy-ß-methylbutyrate (HMB, metabolite of leucine) influences general growth and mechanical endurance of long bones in newborn offspring in sex-dependent manner. The present experiment was conducted to evaluate the effect of HMB treatment of pregnant sows on bone development in offspring at weaning. From 70th day until the 90th day of gestation, sows received either a basal diet (n = 12) or the same diet supplemented with HMB (n = 12) at the dose of 0.2 g/kg of body weight/day. Femora obtained from six males and females in each group weaned at the age of 35 days were examined. Maternal HMB treatment significantly enhanced body weight and changed bone morphology increasing femur mechanical strength in both sexes. Maternal HMB supplementation also elevated bone micro- and macroelement concentrations and enhanced content of proteoglycans in articular cartilage. Based on the obtained results, it can be concluded that maternal HMB supplementation in the mid-gestation period significantly accelerated bone development in both sexes by upregulation of a multifactorial system including leptin and osteoprotegerin. However, the sex (irrespective of the HMB treatment) was the factor which influenced the collagen structure in cartilages and trabecular bone, as demonstrated both by the Picrosirius red staining and performed analysis of thermal stability of collagenous tissues. The structural differences in collagen between males and females were presumably related to a different collagen maturity. No studies conducted so far provided a detailed morphological analysis of bone, articular cartilage, growth plate and the activities of the somatotropic and pituitary-gonadal axes, as well as leptin/osteoprotegerin system in weaned offspring prenatally treated with HMB. This study showed also the relationship between the maternal HMB treatment and bone osteometric and mechanical traits, hormones, and growth and bone turnover markers such as leptin, osteoprotegerin and insulin-like growth factor-1.


Assuntos
Dieta/veterinária , Suplementos Nutricionais , Cartilagem Hialina/efeitos dos fármacos , Leptina/metabolismo , Suínos , Valeratos/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Fenômenos Biomecânicos , Desenvolvimento Ósseo/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Cartilagem Hialina/crescimento & desenvolvimento , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal , Distribuição Aleatória , Valeratos/administração & dosagem
16.
Biomolecules ; 9(12)2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888249

RESUMO

In this paper, the application of a non-ionic detergent Cremophor EL for monomerization of chlorophyll a in an aqueous medium is studied. The spectrophotometric properties of chlorophyll a encapsulated into the Cremophor EL nano-emulsion system were characterized by electronic absorption, steady-state and time-resolved fluorescence as well as circular dichroism spectroscopy. The results have shown that chlorophyll a dissolves more efficiently in the aqueous medium containing low-level Cremophor (5 wt%) than at an ethanolic solution even in the concentration of 10-4 M. The molecular organization of the chlorophyll a in the Cremophor EL nano-micelles was also investigated by means of Raman spectroscopy. The spectral changes in the frequency of the C=O stretching group were used to distinguish the aggregation state of chlorophyll. It was revealed that chlorophyll a exists dominantly in the monomeric form in the Cremophor EL aqueous solution. The promising aspect of the use of Cremophor EL nano-emulsion as a delivery system is to maintain stable chlorophyll monomer in an aqueous medium. It would open the potential for a new, practical application of chlorophyll a in medicine, as a dietary supplement or studies on molecular organization of chlorophyll a in the well-defined artificial system.


Assuntos
Clorofila A/química , Glicerol/análogos & derivados , Nanopartículas/química , Tensoativos/química , Água/química , Soluções Tampão , Clorofila A/isolamento & purificação , Emulsões/química , Etanol/química , Glicerol/química , Fosfatos/química
17.
PLoS One ; 13(12): e0208921, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30533027

RESUMO

This study was focused on analyzing the effects of dietary inclusion of raw chickpea seed as a replacement of soybean meal as a primary protein source on bone structure in broiler chickens. Broiler chickens (n = 160) received in their diet either soybean meal (SBM) or raw chickpea seeds (CPS) as a primary protein source throughout the whole rearing period (n = 80 in each group). On the 42th day randomly selected chickens from each group (n = 8) were slaughtered. Collected tibiotarsus were subjected to examination of the biomechanical characteristics of bone mid-diaphysis, microstructure of the growth plate and articular cartilages; the analysis of mineral content and crystallinity of mineral phase, and the measurements of thermal stability of collagen in hyaline cartilage were also carried out. The inclusion of chickpea seeds resulted in increase of bone osteometric parameters (weight, length and mid-diaphysis cross-sectional area) and mechanical endurance (yield load, ultimate load, stiffness, Young modulus). However, when loads were adjusted to bone shape (yield and ultimate stress) both groups did not differ. Mineral density determined by means of densitometric measurements did not differ between groups, however the detailed analysis revealed the differences in the macro- and microelements composition. The results of FT-IR and XRD analyses showed no effect of diet type on mineral phase crystallinity and hydroxyapatite nanocrystallites size. In trabecular bone, the increase of real bone volume (BV/TV) and number of trabeculae was observed in the CPS group. Total thickness of articular cartilage was the same in both groups, save the transitional zone, which was thicker in the SBM group. The total thickness of the growth plate cartilage was significantly increased in the CPS group. The area of the most intense presence of proteoglycans was wider in the SBM group. The structural analysis of fibrous components of bone revealed the increase of fraction of thin, immature collagen content in articular cartilage, trabeculae and compact bone in the CPS group. The dietary inclusion of CPS affected the thermal stability of collagen, as decrease of net denaturation enthalpy was observed. This study showed a beneficial effect of CPS on the skeletal development, improving the overall bone development and the microarchitecture of cancellous bone. It suggests that CPS can be a promising replacement for SBM in broilers feeding in the aspect of animal welfare related to the development of the skeletal system.


Assuntos
Osso e Ossos/metabolismo , Galinhas/metabolismo , Cicer/química , Dieta/veterinária , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/efeitos dos fármacos , Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/química , Calcificação Fisiológica/efeitos dos fármacos , Galinhas/crescimento & desenvolvimento , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/metabolismo , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Poult Sci ; 96(2): 491-500, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27591270

RESUMO

The effect of caponization on the mechanical properties of Polbar chicken bones was the subject of investigation. The biomechanical strength of bones and the risk of their deformation or fracture were determined on the basis of their geometric, structural, material, and densitometric properties. Eight-week-old cockerels of Polbar breed were surgically castrated and then fattened until the 24th week of life. It was observed that caponization did not influence the weight and length of either of the long bones. It did however significantly reduce their ash content and the Ca and P contents in their femur, and P content in their tibia. Dual energy x-ray absorptiometry densitometry revealed that bone mineral content of the mid-diaphyseal part of both bones were reduced. Similarly, the bone tissue density of bones decreased. Caponization influenced the bone's geometric structure increasing the internal and external diameters of the bones. The bone cross-sectional area was greater in capons, and, consequently, the cross-sectional moment of inertia and the radius of gyration significantly increased. However, the relative wall thickness and cortical index were not altered. The three-point bending tests revealed the negative effect of caponization on the mechanical endurance of bones. Yield strength, Young modulus, and yield stress, characterizing the strength of the bone's material, decreased in capons. That suggests a higher risk of permanent deformation as capon bones become less elastic. Concluding, caponization negatively influenced the quality characteristics of Polbar chicken long bones.


Assuntos
Densidade Óssea , Galinhas/fisiologia , Fêmur/química , Orquiectomia/veterinária , Tíbia/química , Absorciometria de Fóton/veterinária , Animais , Fenômenos Biomecânicos , Masculino , Distribuição Aleatória
19.
Arch Oral Biol ; 70: 24-31, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27300492

RESUMO

OBJECTIVE: The aim of this research was to check the effect of the prenatally administered ß-hydroxy ß-methylbutyrate (HMB) on the development of enamel surface of the spiny mice offspring. DESIGN: The spiny mice dams were randomly assigned into three groups: control group (not supplemented with HMB) and two experimental groups in which powdered HMB was given at the daily dosage of 0.2g/kg of body weight (group I) and 0.02g/kg of body weight (group II) during the last period of gestation. Newborn pups were euthanized by CO2 inhalation. The morphology of incisor teeth was analysed using atomic force microscopy (AFM) in semi-contact mode in the height, magnitude and phase domains. Height images became a basis for determination of surface roughness parameters. RESULTS: Conducted study indicated that maternal HMB administration markedly influences enamel development. Enamel of offspring's teeth in both experimental groups was characterized by significantly smaller values of indices describing surface roughness and profile. HMB supplementation influenced the calculated parameters regardless of the diet type and offspring sex, however higher dose of HMB caused stronger changes in enamel surface's physical properties and could be observed in higher intensity in the male group. CONCLUSIONS: HMB administration caused reduction in the irregularities of enamel surface, thereby possibly reducing the probability of bacteria adhesion and caries development. These observations may serve to improve nutrition and supplementation of animals and could be a lead for further research.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Propriedades de Superfície/efeitos dos fármacos , Valeratos/farmacologia , Animais , Animais Recém-Nascidos , Peso Corporal , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Esmalte Dentário/diagnóstico por imagem , Esmalte Dentário/microbiologia , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Incisivo/diagnóstico por imagem , Incisivo/efeitos dos fármacos , Incisivo/crescimento & desenvolvimento , Incisivo/ultraestrutura , Masculino , Camundongos , Microscopia de Força Atômica/métodos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória
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