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1.
Iran J Med Sci ; 49(4): 205-218, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38680225

RESUMO

Physical activity has a positive effect on human health and emotional well-being. However, in both amateur and professional athletes, training poses a risk of acute or chronic injury through repetitive overloading of bones, joints, and muscles. Inflammation can be an adverse effect of intense exercise caused by several factors including oxidative stress. The present narrative review summarizes current knowledge on inflammatory markers induced by physical exercise. Post-exercise recovery may reduce inflammatory responses and is key to effective training and adaptation of muscle tissues to sustained physical exertion.


Assuntos
Exercício Físico , Fibronectinas , Inflamação , alfa 1-Antitripsina , Humanos , Exercício Físico/fisiologia , Exercício Físico/psicologia , Fibronectinas/sangue , alfa 1-Antitripsina/sangue
2.
Microorganisms ; 11(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37630541

RESUMO

Laboratory diagnosis of Toxoplasma gondii infection plays a crucial role in ensuring the safety of blood recipients, especially in the case of immunosuppressed people, such as organ transplant patients. Toxoplasmosis, caused by the parasite Toxoplasma gondii, is a potential threat to people with weakened immune systems, and blood transfusions from infected donors can lead to severe complications. In this publication, we analyze the medical relevance of Toxoplasma infection in the context of the safety of blood recipients, focusing on the immunosuppressed patient population. We present various diagnostic methods, such as serological, molecular, and microscopic tests, which can detect the presence of Toxoplasma gondii in donors' blood. We also discuss the importance of adequately interpreting diagnostic results, considering risk factors, and detectability of the infection. We pay special attention to high-sensitivity and -specificity diagnostic techniques, which allow us to minimize the risk of Toxoplasma gondii transmission to blood recipients. Our findings have important implications for clinical practice and organ transplantation guidelines, emphasizing the need to diagnose and monitor Toxoplasma infections in blood donors and recipients.

3.
Antioxidants (Basel) ; 12(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36978981

RESUMO

Ferroptosis is a recently discovered form of programmed cell death. It is characterized by the accumulation of iron and lipid hydroperoxides in cells. Vitamin K is known to have antioxidant properties and plays a role in reducing oxidative stress, particularly in lipid cell membranes. Vitamin K reduces the level of reactive oxygen species by modulating the expression of antioxidant enzymes. Additionally, vitamin K decreases inflammation and potentially prevents ferroptosis. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leading to coronavirus disease 2019 (COVID-19) is associated with oxidant-antioxidant imbalance. Studies have shown that intensified ferroptosis occurs in various tissues and cells affected by COVID-19. Vitamin K supplementation during SARS-CoV-2 infection may have a positive effect on reducing the severity of the disease. Preliminary research suggests that vitamin K may reduce lipid peroxidation and inhibit ferroptosis, potentially contributing to its therapeutic effects in COVID-19 patients. The links between ferroptosis, vitamin K, and SARS-CoV-2 infection require further investigation, particularly in the context of developing potential treatment strategies for COVID-19.

4.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902266

RESUMO

Impaired levels of selenium (Se), zinc (Zn), copper (Cu), iron (Fe), manganese (Mn) and iodine (I) in the organism may adversely affect the thyroid endocrine system. These trace elements play a role in the fight against oxidative stress as components of enzymes. Oxidative-antioxidant imbalance is considered a possible factor in many pathological conditions, including various thyroid diseases. In the available literature, there are few scientific studies showing a direct correlation of the effect of supplementation of trace elements on slowing down or preventing the occurrence of thyroid diseases in combination with the improvement of the antioxidant profile, or through the action of these elements as antioxidants. Among the available studies, it has been shown that an increase in lipid peroxidation levels and a decrease in the overall antioxidant defense status occur during such thyroid diseases as thyroid cancer, Hashimoto's thyroiditis and dysthyroidism. In studies in which trace elements were supplemented, the following were observed: a decrease in the level of malondialdehyde after supplementation with Zn during hypothyroidism and reduction in the malondialdehyde level after Se supplementation with a simultaneous increase in the total activity status and activity of antioxidant defense enzymes in the course of autoimmune thyroiditis. This systematic review aimed to present the current state of knowledge about the relationship between trace elements and thyroid diseases in terms of oxidoreductive homeostasis.


Assuntos
Selênio , Doenças da Glândula Tireoide , Oligoelementos , Humanos , Antioxidantes , Zinco , Cobre , Homeostase , Malondialdeído
5.
Metabolites ; 13(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36837762

RESUMO

Baths in cold water are a popular physical activity performed to improve health. This study aimed to determine whether repeated cold-water exposure leads to the up-regulation of antioxidant defenses and whether or not this leads to a reduction in basal and/or acute pulses of oxidative distress in humans. The study group consisted of 28 healthy male members of the WS club (average age 39.3 ± 6.1 years). The study sessions occurred at the beginning and the end of the WS season. During the WS season, the participants took 3-min cold-water baths in a cold lake once a week. Blood samples were collected three times during each session: before the bath, 30 min after the bath, and 24 h after the bath. The activity of selected antioxidant enzymes, including superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx), as well as the concentration of lipid peroxidation (LPO) products, including thiobarbituric acid-reactive substances (TBARS) and conjugated dienes (CD), were determined in erythrocytes. The concentration of TBARS, CD, retinol, and α-tocopherol were determined in the blood plasma, whereas the level of other LPO products, including 4-hydroxynonenal and 8-iso-prostaglandin F2α, were determined in the blood serum. The repeated cold exposure up-regulated most antioxidant defenses, and this led to an attenuation of most indicators of oxidative stress at the baseline and acute pulses in response to cold exposure. In conclusion, due to regular cold exposure, the antioxidant barrier of winter swimmers was stimulated. Thus, short cold-bath sessions seem to be an effective intervention, inducing promoting positive adaptive changes such as the increased antioxidant capacity of the organism.

6.
Pathogens ; 12(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36839588

RESUMO

Giardia intestinalis is one of the most common food-borne protozoa. The sensitivity of pathogens to physical and chemical factors is the basis for developing measures to reduce the incidence of the population. Several methods are available to detect the presence of G. intestinalis. The study determines the influence of 22 selected factors on the survival assessment and detection of G. intestinalis DNA in trophozoites axenically cultured. The influence of a given factor on the test result was observed in the case of 17 factors (77.3%) in the microscopic method, while only in the case of 3 (13.6%) substances in the real-time PCR method. Prevention of G. intestinalis infections, e.g., by ensuring food and water safety, is a crucial issue affecting public health. The experiment was conducted on trophozoites as the first approach. It is necessary to continue research and observe the epidemiological situation. In future studies, the impact of the studied factors on the survival assessment and detection of Giardia intestinalis DNA in axenically cultured cysts should be determined.

7.
Pathogens ; 12(1)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36678458

RESUMO

Toxoplasma gondii is a worldwide distributed protozoan parasite. This apicomplexan parasite infects one-third of the population worldwide, causing toxoplasmosis, considered one of the neglected parasitic infections. In healthy humans, most infections are asymptomatic. However, in immunocompromised patients, the course of the disease can be life-threatening. Human immunodeficiency virus (HIV)-infected patients have a very high burden of Toxoplasma gondii co-infection. Thus, it is essential to use modern, sensitive, and specific methods to properly monitor the course of toxoplasmosis in immunodeficient patients.

8.
Antioxidants (Basel) ; 13(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38247462

RESUMO

Oxidative stress plays a significant role in the development and course of parasitic infections, both in the attacked host organism and the parasite organism struggling to survive. The host uses large amounts of reactive oxygen species (ROS), mainly superoxide anion (O2•-) and hydrogen peroxide (H2O2), to fight the developing parasitic disease. On the other hand, the parasite develops the most effective defense mechanisms and resistance to the effects of ROS and strives to survive in the host organism it has colonized, using the resources and living environment available for its development and causing the host's weakening. The paper reviews the literature on the role of oxidative stress in parasitic diseases, which are the most critical epidemiological problem worldwide. The most common parasitosis in the world is malaria, with 300-500 million new cases and about 1 million deaths reported annually. In Europe and Poland, the essential problem is intestinal parasites. Due to a parasitic infection, the concentration of antioxidants in the host decreases, and the concentration of products of cellular components oxidation increases. In response to the increased number of reactive oxygen species attacking it, the parasites have developed effective defense mechanisms, including primarily the action of antioxidant enzymes, especially superoxide dismutase and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-dependent complexes glutathione and thioredoxin.

9.
Antioxidants (Basel) ; 11(12)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36552653

RESUMO

Physical activity has a positive effect on human health and well-being, but intense exercise can cause adverse changes in the organism, leading to the development of oxidative stress and inflammation. The aim of the study was to determine the effect of short-term cold water immersion (CWI) and a sauna bath as methods of postexercise regeneration on the indicators of inflammation and oxidative damage in the blood of healthy recreational athletes. Forty-five male volunteers divided into two groups: 'winter swimmers' who regularly use winter baths (n = 22, average age 43.2 ± 5.9 years) and 'novices' who had not used winter baths regularly before (n = 23, mean age 25 ± 4.8 years) participated in the study. The research was divided into two experiments, differing in the method of postexercise regeneration used, CWI (Experiment I) and a sauna bath (Experiment II). During Experiment I, the volunteers were subjected to a 30-min aerobic exercise, combined with a 20-min rest at room temperature (RT-REST) or a 20-min rest at room temperature with an initial 3-min 8 °C water bath (CWI-REST). During the Experiment II, the volunteers were subjected to the same aerobic exercise, followed by a RT-REST or a sauna bath (SAUNA-REST). The blood samples were taken before physical exercise (control), immediately after exercise and 20 min after completion of regeneration. The concentrations of selected indicators of inflammation, including interleukin 1ß (IL-1ß), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 8 (IL-8), interleukin 10 (IL-10), transforming growth factor ß1 (TGF-ß1) and tumor necrosis factor α (TNF-α), as well as the activity of indicators of oxidative damage: α1-antitrypsin (AAT) and lysosomal enzymes, including arylsulfatase A (ASA), acid phosphatase (AcP) and cathepsin D (CTS D), were determined. CWI seems to be a more effective post-exercise regeneration method to reduce the inflammatory response compared to a sauna bath. A single sauna bath is associated with the risk of proteolytic tissue damage, but disturbances of cellular homeostasis are less pronounced in people who regularly use cold water baths than in those who are not adapted to thermal stress.

10.
Ann Agric Environ Med ; 28(4): 709-712, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34969233

RESUMO

INTRODUCTION: Cutaneous larva migrans (CLM) is a zoonotic disease caused by hookworms characteristic of tropical and subtropical regions. In Poland, new cases appear every year in patients who have travelled to tropical areas. Most of the cases are initially under-diagnosed, which results in a delay in starting proper treatment. CASE REPORT: A 49-year-old woman presented to the Outpatient Dermatology Clinic with a pruritic and fibrous cutaneous lesion on the plantar region of her left foot. She had returned from a tourist trip to Honduras one week before the skin lesion erupted. RESULTS: The diagnosis of CLM due to Ancylostoma sp. infestation was confirmed. Locally applied cryotherapy was ineffective. The oral treatment of albendazole resulted in complete resolution of the symptoms without recurrence after a 6-month follow up period. CONCLUSIONS: CLM should be considered in travellers to tropical countries. Oral anti-parasitic agents seem to be more effective than topical treatment for dermatosis.


Assuntos
Larva Migrans , Animais , Feminino , Humanos , Larva Migrans/diagnóstico , Larva Migrans/tratamento farmacológico , Pessoa de Meia-Idade , Polônia , Viagem , Zoonoses
11.
Oxid Med Cell Longev ; 2021: 2364931, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721756

RESUMO

Lip, oral cavity, and pharyngeal cancers (LOCP) constitute a group of rare neoplasms with unfavorable prognosis. So far, not much is known about the role of vitamin D and oxidative stress in the pathogenesis of LOCP in the European population. The aim of the study was to determine the concentrations of vitamin D, osteopontin, melatonin, and malondialdehyde (MDA) as markers of oxidative stress and/or inflammation, as well as the activities of antioxidant enzymes in the course of LOCP. The vitamin D, melatonin, and osteopontin concentrations in blood serum, the MDA levels in erythrocytes and blood plasma, and the activities of superoxide dismutase (SOD-1), catalase (CAT), and glutathione peroxidase (GPx) in erythrocytes were measured in blood samples taken from 25 LOCP patients of middle age (YCG), 20 LOCP elderly patients (OCG), and 25 healthy middle-aged volunteers. In both cancer groups, decreases in vitamin D and CAT, as well as increases in osteopontin and blood plasma MDA, were observed. An increase in GPx activity in YCG and a decrease in melatonin level in OCG were found. The results indicate the vitamin D deficiency and disturbed oxidant-antioxidant homeostasis in LOCP patients. Osteopontin seems to be associated with LOCP carcinogenesis and requires further research.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Labiais/sangue , Melatonina/sangue , Neoplasias Bucais/sangue , Osteopontina/sangue , Estresse Oxidativo , Neoplasias Faríngeas/sangue , Deficiência de Vitamina D/sangue , Vitamina D/sangue , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Labiais/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Faríngeas/diagnóstico , Deficiência de Vitamina D/diagnóstico
12.
J Clin Med ; 10(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34575347

RESUMO

Cold-water immersion (CWI) after exercise is a method used by sportsmen to improve recovery. The aim of the study was to assess the effect of a 3 min CWI on the inflammatory state by measuring levels of interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor α (TNF-α), and transforming growth factor ß1 (TGF-ß1), and activities of α1-antitrypsin (AAT) and lysosomal enzymes, including arylsulfatase (ASA), acid phosphatase (AcP), and cathepsin D (CTS D), in the blood of healthy recreational athletes. Male volunteers (n = 22, age 25 ± 4.8 yr) performed a 30 min submaximal aerobic exercise, followed by a 20 min rest at room temperature (RT-REST) or a 20 min rest at room temperature with an initial 3 min 8 °C water bath (CWI-REST). Blood samples were taken at baseline, immediately after exercise, and after 20 min of recovery. The IL-6, IL-10, and TNF-α levels and the AAT activity increased significantly immediately after exercise. The IL-6 level was significantly higher after CWI-REST than after RT-REST. No changes in the activities of the lysosomal enzymes were observed. The effect of a 3 min CWI on the level of inflammatory markers during post-exercise recovery was limited. Thus, it might be considered as a widely available method of regeneration for recreational athletes.

13.
Int J Mol Sci ; 22(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071892

RESUMO

Toxoplasma gondii is an apicomplexan parasite causing toxoplasmosis, a common disease, which is most typically asymptomatic. However, toxoplasmosis can be severe and even fatal in immunocompromised patients and fetuses. Available treatment options are limited, so there is a strong impetus to develop novel therapeutics. This review focuses on the role of oxidative stress in the pathophysiology and treatment of T. gondii infection. Chemical compounds that modify redox status can reduce the parasite viability and thus be potential anti-Toxoplasma drugs. On the other hand, oxidative stress caused by the activation of the inflammatory response may have some deleterious consequences in host cells. In this respect, the potential use of natural antioxidants is worth considering, including melatonin and some vitamins, as possible novel anti-Toxoplasma therapeutics. Results of in vitro and animal studies are promising. However, supplementation with some antioxidants was found to promote the increase in parasitemia, and the disease was then characterized by a milder course. Undoubtedly, research in this area may have a significant impact on the future prospects of toxoplasmosis therapy.


Assuntos
Antioxidantes/uso terapêutico , Interações Hospedeiro-Parasita , Estresse Oxidativo/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico , Toxoplasmose/metabolismo , Adaptação Biológica , Animais , Antioxidantes/farmacologia , Gerenciamento Clínico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Estágios do Ciclo de Vida , Oxidantes/metabolismo , Oxirredução , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasma/fisiologia , Toxoplasmose/parasitologia , Toxoplasmose/prevenção & controle
14.
Antioxidants (Basel) ; 11(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35052600

RESUMO

It has been proven that physical exercise improves cognitive function and memory, has an analgesic and antidepressant effect, and delays the aging of the brain and the development of diseases, including neurodegenerative disorders. There are even attempts to use physical activity in the treatment of mental diseases. The course of most diseases is strictly associated with oxidative stress, which can be prevented or alleviated with regular exercise. It has been proven that physical exercise helps to maintain the oxidant-antioxidant balance. In this review, we present the current knowledge on redox balance in the organism and the consequences of its disruption, while focusing mainly on the brain. Furthermore, we discuss the impact of physical activity on aging and brain diseases, and present current recommendations and directions for further research in this area.

15.
Oxid Med Cell Longev ; 2020: 1835352, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802258

RESUMO

OBJECTIVE: To determine the concentration of thiobarbituric acid reactive substances (TBARS) in erythrocytes and blood plasma, and the activities of selected antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in erythrocytes in patients receiving hyperbaric oxygen (HBO) treatment due to difficult-to-heal "skin wounds". Material and Methods. Indices of oxidative stress were assessed in venous blood taken from 23 patients three times: immediately before HBO procedure, approx. 5 minutes after leaving the hyperbaric chamber, and after 25 HBO procedures. Moreover, selected blood counts were measured in the collected material two times: prior to treatment and after 25 HBO procedures. RESULTS: A statistically significant positive correlation between the CAT activity and the TBARS concentration in the erythrocytes of patients was found before treatment in the hyperbaric chamber (r = 0.394; P ≤ 0.05). No statistically significant changes in the TBARS concentration in erythrocytes and blood plasma were observed both after the first HBO procedure and after 25 procedures. No statistically significant changes in the activities of CAT, SOD, and GPx were noted. Platelet count decreased by 18.7% (P ≤ 0.05) after 25 HBO procedures. Granulocyte count decreased by approx. 21% (P ≤ 0.05), and granulocyte percentage by 11.8% (P ≤ 0.01). In turn, the percentage of lymphocytes and monocytes increased after the treatment by 16.6% (P < 0.05) and 16.4% (P < 0.05), respectively. CONCLUSIONS: Exposure to HBO due to difficult-to-heal skin wounds does not significantly affect the levels of oxidative stress in the peripheral blood of patients and, from the point of view of oxidation-reduction processes, appears to be a safe therapeutic method for the treatment of chronic wounds.


Assuntos
Oxigenoterapia Hiperbárica/métodos , Pele/patologia , Cicatrização/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo
16.
Ann Agric Environ Med ; 27(1): 66-75, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32208582

RESUMO

OBJECTIVE: The aim of the study was to determine the effect of nesfatin-1 on bone properties in female rats in the conditions of developing osteopenia induced by ovariectomy (OVX). MATERIAL AND METHODS: The experiment was performed on 21 female Wistar rats assigned to 3 groups receiving intraperitoneally physiological saline (SHO, OVX-PhS) and nesfatin-1 in dose 2 µg/kg BW of (OVX-NES) once a day for 8 wks. At the end of the experiment, the rats were scanned using the DXA method to determine the body composition, tBMC, and tBMD. The isolated femora and tibia were tested with the DXA method for BMD and BMC, and with the pQCT method for separate analysis of the cortical and trabecular bone tissue. The bone strength parameters were also determined. The immunohistochemical method was used for determination of nesfatin-1 localization in growth cartilage. Bone metabolism markers (osteocalcin, bALP, and NTx) were identified using an ELISA kit. RESULTS: OVX exerts a negative effect on bone tissue. The nesfatin-1 administration influenced positively the DXA parameters of tibia. TvBMD and TbvBMD measured by pQCT in metaphysis of bones were significantly higher in the OVX-NES group than in OVX-PhS. No differences were found in the values of bone strength parameters between SHO and OVX-NES females. Extra- and intracellular immunohistochemical reaction for nesfatin-1 was observed in all zones of growth cartilage, with the strongest reaction detected in the calcifying zone. Nesfatin-1 administration caused a significant increase in the osteocalcin and bALP concentration in relation to the OVX-PhS animals. CONCLUSIONS: The results of the experiment indicate that nesfatin-1 exerts a protective effect on bone tissue properties and can be used in the prevention of osteoporosis.


Assuntos
Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/tratamento farmacológico , Nucleobindinas/farmacologia , Absorciometria de Fóton , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/metabolismo , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Osteocalcina/metabolismo , Ovariectomia , Ratos Wistar , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos
17.
Oxid Med Cell Longev ; 2017: 8494107, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29142618

RESUMO

Obesity is one of the major global health problems. Melatonin deficiency has been demonstrated to correlate with obesity. The aim of the study was to estimate the effect of melatonin on oxidative stress and adipokine levels in obese patients on a calorie-restricted diet. Thirty obese patients were supplemented with a daily dose of 10 mg of melatonin (n = 15) or placebo (n = 15) for 30 days with a calorie-restricted diet. Serum levels of melatonin, 4-hydroxynonenal (HNE), adiponectin, omentin-1, leptin, and resistin, as well as erythrocytic malondialdehyde (MDA) concentration and Zn/Cu-superoxide dismutase, catalase, and glutathione peroxidase (GPx) activities, were measured at baseline and after supplementation. Significant body weight reduction was observed only in the melatonin group. After melatonin supplementation, the adiponectin and omentin-1 levels and GPx activities statistically increased, whereas the MDA concentrations were reduced. In the placebo group, a significant rise in the HNE and a drop in the melatonin concentrations were found. The results show evidence of increased oxidative stress accompanying calorie restriction. Melatonin supplementation facilitated body weight reduction, improved the antioxidant defense, and regulated adipokine secretion. The findings strongly suggest that melatonin should be considered in obesity management. This trial is registered with CTRI/2017/07/009093.


Assuntos
Adipocinas/sangue , Restrição Calórica , Melatonina/administração & dosagem , Obesidade , Estresse Oxidativo/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Obesidade/sangue , Obesidade/terapia
18.
Anal Bioanal Chem ; 409(24): 5747-5755, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28748313

RESUMO

Regeneration of bone defects was promoted by a novel ß-glucan/carbonate hydroxyapatite composite and characterized by Raman spectroscopy, microCT and electron microscopy. The elastic biomaterial with an apatite-forming ability was developed for bone tissue engineering and implanted into the critical-size defects of rabbits' tibiae. The bone repair process was analyzed on non-decalcified bone/implant sections during a 6-month regeneration period. Using spectroscopic methods, we were able to determine the presence of amides, lipids and assign the areas of newly formed bone tissue. Raman spectroscopy was also used to assess the chemical changes in the composite before and after the implantation process. SEM analyses showed the mineralization degree in the defect area and that the gap size decreased significantly. Microscopic images revealed that the implant debris were interconnected to the poorly mineralized inner side of a new bone tissue. Our study demonstrated that the composite may serve as a biocompatible background for collagen ingrowth and exhibits the advantages of applying Raman spectroscopy, SEM and microCT in studying these samples.


Assuntos
Substitutos Ósseos/química , Cerâmica/química , Durapatita/química , beta-Glucanas/química , Animais , Substitutos Ósseos/uso terapêutico , Cerâmica/uso terapêutico , Durapatita/uso terapêutico , Módulo de Elasticidade , Masculino , Teste de Materiais , Próteses e Implantes , Coelhos , Análise Espectral Raman , Tíbia/lesões , Tíbia/patologia , Tíbia/cirurgia , Tíbia/ultraestrutura , beta-Glucanas/uso terapêutico
19.
Anal Bioanal Chem ; 407(25): 7775-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26277184

RESUMO

The spectroscopic approaches of FTIR imaging and Raman mapping were applied to the characterisation of a new carbon hydroxyapatite/ß-glucan composite developed for bone tissue engineering. The composite is an artificial bone material with an apatite-forming ability for the bone repair process. Rabbit bone samples were tested with an implanted bioactive material for a period of several months. Using spectroscopic and chemometric methods, we were able to determine the presence of amides and phosphates and the distribution of lipid-rich domains in the bone tissue, providing an assessment of the composite's bioactivity. Samples were also imaged in transmission using an infrared microscope combined with a focal plane array detector. CaF2 lenses were also used on the infrared microscope to improve spectral quality by reducing scattering artefacts, improving chemometric analysis. The presence of collagen and lipids at the bone/composite interface confirmed biocompatibility and demonstrate the suitability of FTIR microscopic imaging with lenses in studying these samples. It confirmed that the composite is a very good background for collagen growth and increases collagen maturity with the time of the bone growth process. The results indicate the bioactive and biocompatible properties of this composite and demonstrate how Raman and FTIR spectroscopic imaging have been used as an effective tool for tissue characterisation.


Assuntos
Substitutos Ósseos/química , Osso e Ossos/ultraestrutura , Durapatita/química , Alicerces Teciduais/química , beta-Glucanas/química , Animais , Osso e Ossos/química , Implantes Experimentais , Masculino , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Engenharia Tecidual
20.
Mater Sci Eng C Mater Biol Appl ; 53: 60-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26042691

RESUMO

A novel elastic hydroxyapatite-based composite of high surgical handiness has been developed. Its potential application in orthopedics as a filler of bone defects has been studied. The biomaterial was composed of carbonated hydroxyapatite (CHAP) granules and polysaccharide polymer (ß-1,3-glucan). Cylinders of 4mm in diameter and 6mm in length were implanted into bone cavities created in the proximal metaphysis of tibiae of 24 New Zealand white rabbits. 18 sham-operated animals were used as controls. After 1, 3 or 6 months, the rabbits were euthanized, the bones were harvested and subjected to analysis. Radiological images and histological sections revealed integration of implants with bone tissue with no signs of graft rejection. Peripheral quantitative computed tomography (pQCT) indicated the stimulating effect of the biomaterial on bone formation and mineralization. Densitometry (DXA) analysis suggested that biomineralization of bones was preceded by bioresorption and gradual disappearance of porous ceramic granules. The findings suggest that the CHAP-glucan composite material enables regeneration of bone tissue and could serve as a bone defect filler.


Assuntos
Materiais Biocompatíveis/farmacologia , Durapatita/farmacologia , Tíbia/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , beta-Glucanas/farmacologia , Animais , Materiais Biocompatíveis/química , Durapatita/química , Masculino , Coelhos , Tíbia/lesões , beta-Glucanas/química
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