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11.
We examined astroglial cells in the brain of the pygmy shrew Sorex minutus (Insectivora). For that purpose we labeled glial fibrillary acidic protein (GFAP) immunohistochemically in brain sections with a polyclonal antibody. Antigen retrieval experiments were performed to counteract formaldehyde fixation masking of GFAP epitopes. Our results showed remarkable paucity of GFAP-immunoreactive cells and fibers in the cerebral cortex and nuclei, as well as in the majority of the diencephalic and mesencephalic structures. In the forebrain, significant numbers of GFAP-containing astrocytes were found only in the ependyma and subventricular zones, superficial part of layer I of the cerebral cortex, and the majority of white matter structures. In the diencephalon, habenular nuclei were rich in GFAP-immunopositive astrocytes and labeled radial fibers were extended between median eminence and the third ventricle. A considerably higher density of labeled astrocytes was detected in the caudal brainstem and cerebellum. In contrast, in the mouse brain, immunoreactive astrocytes were present in large quantities in various structures. Staining of sections of the shrew brain against glutamine synthetase revealed abundance of immunofluorescent astrocytes in many areas, especially in the shrew cerebral cortex. It seems probable that in the shrew brain only a limited fraction of astroglia expresses GFAP, while other astroglial cells can be detected with different markers. It is possible that the rodent type of astroglial GFAP expression might not be common to insectivores and probably to some other mammalian orders. 相似文献
12.
Linear, biodegradable, aliphatic polyurethanes with various degrees of hydrophilicity were synthesized in bulk at 50-100 degrees C. The ratios between the hydrophilic and hydrophobic segments were 0:100, 30:70, 40:60, 50:50, and 70:30, respectively. The hydrophilic segment consisted of poly(ethylene oxide) (PEO) diol (molecular weight = 600 or 2000) or the poly(ethylene-propylene-ethylene oxide) (PEO-PPO-PEO) diol Pluronic F-68 (molecular weight = 8000). The hydrophobic segment was made of poly(epsilon-caprolactone) diol (molecular weight = 530, 1250, or 2000). The chain extenders were 1,4-butane diol and 2-amino-1-butanol. The diisocyanate was aliphatic hexamethylene diisocyanate. The polymers absorbed water in an amount that increased with the increasing content of the PEO segment in the polymer chain. The total amount of absorbed water did not exceed 2% for the poly(ester urethane)s and was as high as 212% for some poly(ester ether urethane)s that behaved in water like hydrogels. The polymers were subjected to in vitro degradation at 37 +/- 0.1 degrees C in phosphate buffer solutions for up to 76 weeks. The poly(ester urethane)s showed 1-2% mass loss at 48 weeks and 1.1-3.8% mass loss at 76 weeks. The poly(ester ether urethane)s manifested 1.6-76% mass loss at 48 weeks and 1.6-96% mass loss at 76 weeks. The increasing content and molecular weight of the PEO segment enhanced the rate of mass loss. Similar relations were also observed for polyurethanes from PEO-PPO-PEO (Pluronic) diols. Materials obtained with 2-amino-1-butanol as the chain extender degraded at a slower rate than similar materials synthesized with 1,4-butane diol. All the materials already manifested a progressive decrease in the molecular weight in the first month of in vitro aging. The rate of molecular weight loss was higher for poly(ester ether urethane)s than for poly(ester urethane)s. For poly(ester ether urethane)s, the rate of molecular weight loss was higher for materials containing Pluronic than for those containing PEO segments. All polymers calcified in vitro. The susceptibility to calcification increased with material hydrophilicity. The progressive deposition of calcium salt on the film surfaces resulted in the formation of large crystal aggregates, the structure of which depended on the chemical composition of the calcified material. Needle-like aggregates, resembling brushite, formed on the hydrophobic polyurethane, and plate-like crystals formed on the highly hydrophilic material. The calcium-to-phosphorus atomic ratio of the crystals growing on the samples was dependent on the chemical composition of the material and varied from 0.94 to 1.55. 相似文献
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Michalak A Wojtas G Kidawa I Tylzanowska-Nitek K 《Pneumonologia i alergologia polska》2004,72(1-2):28-31
A 51-year-old man, heavy cigarette smoker, a homeless alcoholic, with disseminated lesions in lungs and with ulceration and infiltration of the tongue is presented. Treatment with antibiotics was ineffective. He was admitted to the otolaryngological department because of suspicion of the tongue cancer. The histological examination of the tongue biopsy revealed tuberculous granuloma. In the pulmonological department, on admission the patient was cachectic, with massive oedema and ulceration of the tongue, and enlargement of the cervical lymph nodes. He was fed through the gastric tube. He had severe pain of the tongue demanding treatment with opiates analgesics. Chest x-ray revealed disseminated lesions in lungs. Antituberculous therapy was administered because of suspicion of tuberculosis of the tongue and lungs. During the treatment clinical improvement was observed. Tubercule bacilli were grown in the sputum culture after 6 weeks of observation. After 8 weeks of antituberculous therapy regression of lung lesions and healing of the tongue were observed. The patient continued treatment for 6 months in the Lung Disease Outpatient Clinic. 相似文献
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16.
Marcinkiewicz J Biedroń R Maresz K Kwaśny-Krochin B Bobek M Kontny E Maśliński W Chain B 《Archivum immunologiae et therapiae experimentalis》2004,52(4):284-291
INTRODUCTION: Oxidative modification of proteins affects their biological properties. Previously we have shown that hypochlorite (HOCl), the product of activated neutrophils, enhances protein immunogenecity. Collagen type II, a primary component of cartilage, is commonly used in the induction of arthritis in animals (CIA). The aim of this study was to examine whether HOCl may affect immunogenic, tolerogenic, and arthritogenic properties of collagen. MATERIALS AND METHODS: DBA/J mice were injected with either native (CNAT) or chlorinated collagen (CHOCl) to induce arthritis. The effect of chlorination on collagen properties was measured by evaluation of incidence and severity of CIA. Moreover, the concentration of serum anti-collagen IgG antibodies and myeloperoxidase (MPO) activity in inflamed joints was determined. RESULTS: Mice immunized with CNAT in adjuvant developed arthritis (CIA) with an incidence of 69%. CNAT also exerted tolerogenic properties when injected intravenously either before or shortly after primary immunization, resulting in decreased incidence and severity of CIA, reduced MPO activity in inflamed joints, and lowered serum levels of anti-CNAT IgG anti-bodies. Chlorination of collagen significantly diminished its ability to induce CIA and to trigger generation of anti-CNAT IgG antibodies. Interestingly, chlorination did not affect tolerogenic properties of collagen administered prior to primary immunization with CNAT. CONCLUSIONS: These results suggest that chlorination of collagen may selectively affect functional epitopes of collagen. It is likely that in inflamed joints, neutrophil derived HOCl, in some circumstances, will destroy arthritogenic and immunogenic B cell epitopes, while regulatory T cell epitopes will be preserved. 相似文献
17.
ukasz Kopiasz Katarzyna Dziendzikowska Magorzata Gajewska Micha Oczkowski Kinga Majchrzak-Kuligowska Tomasz Krlikowski Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Background: Crohn’s disease (CD) is characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission. The aim of this study was to determine the time-dependent effects of dietary oat beta-glucans on colon apoptosis and autophagy in the CD rat model. Methods: A total of 150 Sprague–Dawley rats were divided into two main groups: healthy control (H) and a TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis (C) group, both including subgroups fed with feed without beta-glucans (βG−) or feed supplemented with low- (βGl) or high-molar-mass oat beta-glucans (βGh) for 3, 7, or 21 days. The expression of autophagy (LC3B) and apoptosis (Caspase-3) markers, as well as Toll-like (TLRs) and Dectin-1 receptors, in the colon epithelial cells, was determined using immunohistochemistry and Western blot. Results: The results showed that in rats with colitis, after 3 days of induction of inflammation, the expression of Caspase-3 and LC3B in intestinal epithelial cells did not change, while that of TLR 4 and Dectin-1 decreased. Beta-glucan supplementation caused an increase in the expression of TLR 5 and Dectin-1 with no changes in the expression of Caspase-3 and LC3B. After 7 days, a high expression of Caspase-3 was observed in the colitis-induced animals without any changes in the expression of LC3B and TLRs, and simultaneously, a decrease in Dectin-1 expression was observed. The consumption of feed with βGl or βGh resulted in a decrease in Caspase-3 expression and an increase in TLR 5 expression in the CβGl group, with no change in the expression of LC3B and TLR 4. After 21 days, the expression of Caspase-3 and TLRs was not changed by colitis, while that of LC3B and Dectin-1 was decreased. Feed supplementation with βGh resulted in an increase in the expression of both Caspase-3 and LC3B, while the consumption of feed with βGh and βGl increased Dectin-1 expression. However, regardless of the type of nutritional intervention, the expression of TLRs did not change after 21 days. Conclusions: Dietary intake of βGl and βGh significantly reduced colitis by time-dependent modification of autophagy and apoptosis, with βGI exhibiting a stronger effect on apoptosis and βGh on autophagy. The mechanism of this action may be based on the activation of TLRs and Dectin-1 receptor and depends on the period of exacerbation or remission of CD. 相似文献
18.
Katarzyna Socha Katarzyna Klimiuk Sylwia K. Naliwajko Jolanta Soroczyska Anna Pucion-Jakubik Renata Markiewicz-ukowska Jan Kochanowicz 《Nutrients》2021,13(2)
Oxidative stress plays a crucial role in the neurodegenerative process and can impair cognitive functions. In the prevention of Alzheimer’s disease (AD), an adequate consumption of dietary antioxidants may be a major factor. The objective of the study was to estimate selenium (Se), copper (Cu), zinc (Zn), and total antioxidant status (TAS) in the serum of patients with AD in relation to their cognitive functions and dietary habits. A total of 110 patients (aged 54–93 years) with early or moderate AD, as well as 60 healthy people (aged 52–83 years) were studied. The severity of the disease was assessed using the mini-mental state examination (MMSE) scale. Food-frequency questionnaires were implemented to collect the dietary data. The concentrations of Se, Cu and Zn in the sera were determined by the atomic absorption spectrometry method. TAS was estimated spectrophotometrically using ready-made kits (Randox). Significantly lower concentrations of Se, Zn and TAS, and higher Cu:Zn ratio in the serum of patients with AD, compared to healthy people, were observed. A low correlation between the MMSE score and TAS in the serum of AD patients and significantly higher MMSE values in patients with TAS above the reference range were also noted. In patients with serum Cu concentration above the norm, significantly lower MMSE values were found. Selected dietary habits such as the frequency of consumption of various food products had a significant impact on the concentration of the assessed parameters in the serum of people with AD. 相似文献
19.
Micha Oczkowski Katarzyna Dziendzikowska Anna Pasternak-Winiarska Dariusz Wodarek Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer. 相似文献
20.
Monika Grabia Anna Pucion-Jakubik Renata Markiewicz-ukowska Joanna Bielecka Anita Mielech Patryk Nowakowski Katarzyna Socha 《Nutrients》2021,13(4)
An appropriate balanced diet and dietary patterns are important at every stage of life, but in the case of young patients with type 1 diabetes mellitus (T1DM), it is especially crucial during the COVID-19 pandemic. The aim of the study was to assess health and nutritional behaviors, mainly adherence to the Mediterranean diet (MD), during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. This survey (based on a questionnaire) was conducted in December 2020 and included 219 young women, healthy (n = 106) and with T1DM (n = 113), from northeast Poland. Over 30% of the study group admitted that they did not engage in any physical activity. A large proportion declared that their screen time was 5–7 h a day (48% in control and 40% in T1DM group). High intakes of sweet-beverages, sweets and red meat, but also low intakes of olive oil, fish and nuts were observed. The vast majority of participants (60% vs. 71%) were moderately adherent to the Mediterranean Diet Adherence Screener (MEDAS). The study demonstrated that despite the similarity between the behaviors of healthy people and those with T1DM, negative health and nutritional practices, such as low physical activity, long screen time, medium and high levels of stress and inappropriate eating habits were observed. 相似文献