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41.
42.
Increased oxytocinergic system activity in the cardiac muscle in spontaneously hypertensive SHR rats
Agnieszka Wsol Agata Gondek Martyna Podobinska Marek Chmielewski Elbieta Sajdel-Sukowska Agnieszka Cudnoch-Jdrzejewska 《Archives of Medical Science》2022,18(4):1088
IntroductionThe present study aimed to determine whether the presence of cardiac hypertrophy due to arterial hypertension is associated with a change in the activity of the oxytocinergic system in cardiomyocytes.Material and methodsThe experiments were performed on male, spontaneously hypertensive rats (SHR, n = 10) and normotensive Wistar-Kyoto rats (WKY, n = 12). Blood samples were collected from both SHR and WKY animals to asses plasma oxytocin (OT) concentration; the rats were sacrificed by decapitation. Samples of the left and right ventricles were harvested for the analysis of the OT and oxytocin receptor (OTR) protein by ELISA, and OT and OTR mRNA expression by RT-PCR. Immunohistopathological studies were performed to confirm the presence of OTR receptors in the cardiac muscle of the ventricles.ResultsPlasma OT concentration did not differ between SHR and WKY rats. In the SHR rats, the expression of OT mRNA and the OT protein level was higher in the left and the right ventricle, while OTR mRNA expression was significantly lower in both the left and the right ventricle. However, the level of OTR protein was higher only in the left ventricle of the SHR rats. The presence of OTR receptors was confirmed by immunohistochemical analysis in the muscle of the right and left ventricle.ConclusionsThe presence of arterial hypertension is associated with increased activity of the oxytocinergic system in the heart, especially in the area of the left ventricle. These findings support the important role of this system in the maintenance of cardiovascular homeostasis. 相似文献
43.
The development of cardiovascular diseases is undoubtedly influenced by improper dietary behavior. The most common mistakes include irregularity of meal consumption, high dietary atherogenicity: snacking on sweets between meals, low supply of dietary fiber, unsaturated fatty acids, legume seeds, and high supply of meat and meat products. Among many food components, some are characterized by a specific cardioprotective effect, which means that their supply of food may prevent the occurrence of cardiovascular disease or improve the health of the sick. Coenzyme Q10 (CoQ10) is one of the ingredients showing cardioprotective effects on the heart and blood vessels. Antioxidant and lipid profile-enhancing effects are also attributed to sitosterol which is one of the plant-derived sterols. A very important argument indicating the necessity of a varied diet rich in a variety of plant products is the beneficial effect of polyphenols, which are most abundant in multicolored vegetables and fruits. Numerous studies show their effectiveness in lowering blood pressure, improving lipid profile, and regeneration of vascular endothelium. The collected publications from the field of lifestyle medicine can be a source of knowledge for dieticians, physicians, and people associated with physical culture and human mental health to prevent the development of cardiovascular diseases and reduce the risk of death from this cause. 相似文献
44.
Maciej Combrzyski Agnieszka Wjtowicz Anna Oniszczuk Dariusz Karcz Jarosaw Szponar Arkadiusz P. Matwijczuk 《Materials》2022,15(14)
The impact of the amount of durum wheat bran additive used on the selected structural, mechanical, and spectroscopic properties of thermoplastic starch moldings was examined in this study. Bran was added to corn starch from 10 to 60% by weight in the blends. Four temperature settings were used for the high-pressure injection: 120, 140, 160, and 180 °C. The highest value of elongation at break (8.53%) was observed for moldings containing 60% bran. Moreover, for these moldings, the tensile strength and flexural strength were lower (appropriately 3.43 MPa and 27.14 MPa). The highest deformation at break (1.56%) were obtained for samples with 60% bran and injection molded at 180 °C. We saw that higher bran content (50 and 60%) and a higher injection molding temperature (160 °C and 180 °C) significantly changed the color of the samples. The most significant changes in the FTIR spectra were observed at 3292 and 1644 cm−1 and in the region of 1460–1240 cm−1. Moreover, notable changes were observed in the intensity ratio of bands at 1015 and 955 cm−1. The changes observed correspond well with the amount of additive used and with the injection temperature applied; thus it may be considered as a marker of interactions affecting plasticization of the material obtained. 相似文献
45.
46.
Joanna Krajewska Krzysztof Nowicki Krzysztof Durka Paulina H. Marek-Urban Patrycja Wiska Tomasz Stpniewski Krzysztof Wo
niak Agnieszka E. Laudy Sergiusz Luliski 《RSC advances》2022,12(36):23099
Two isomeric benzosiloxaborole derivatives 3a and 5a bearing fluorine and 4,4-dimethyl-2-oxazolin-2-yl substituents attached to the aromatic rings were obtained. Both compounds were prone to hydrolytic cleavage of the oxazoline ring after initial protonation or methylation of the nitrogen atom. The derivative 3c featuring N-methylammoniumalkyl ester functionality was successfully subjected to N-sulfonylation and N-acylation reactions to give respective derivatives which demonstrates its potential for modular synthesis of structurally extended benzosiloxaboroles. Compound 5c bearing N-ammoniumalkyl ester underwent conversion to a unique macrocyclic dimer due to siloxaborole ring opening. Furthermore, an unexpected 4-electron reduction of the oxazoline ring occurred during an attempted synthesis of 5a. The reaction gave rise to an unprecedented 7-membered heterocyclic system 4a comprising a relatively stable B–O–B–O–Si linkage and stabilized by an intramolecular N–B coordination. It could be cleaved to derivative 4c bearing BOH and SiMe2OH groups which acts as a pseudo-diol as demonstrated by formation of an adduct with Tavaborole. Apart from the multinuclear NMR spectroscopy characterization, crystal structures of the obtained products were determined in many cases by X-ray diffraction. Investigation of biological activity of the obtained compounds revealed that derivatives 3e and 3f with pendant N-methyl arylsulfonamide groups exhibit high activity against Gram-positive cocci such as methicillin-sensitive Staphylococcus aureus ATCC 6538P, methicillin-resistant S. aureus (MRSA) ATCC 43300 as well as the MRSA clinical strains, with MIC values in the range of 3.12–6.25 mg L−1. These two compounds also showed activity against Enterococcus faecalis ATCC 29212 and Enterococcus faecium ATCC 6057 (with MICs of 25–50 mg L−1). The results of the antimicrobial activity and cytotoxicity studies indicate that 3e and 3f can be considered as potential antibacterial agents, especially against S. aureus MRSA.Transformations of oxazoline–benzosiloxaborole conjugates gave rise to novel boracyclic systems as well as functionalized derivatives featuring antibacterial activity. 相似文献
47.
Gasowska-Bodnar A Bodnar L Wcisło GB Jerzak MM Szczylik C Baranowski W 《Ginekologia polska》2008,79(2):108-114
OBJECTIVES: The aim of our study was to assess the prognostic role of CA 125 regression during neoadjuvant chemotherapy (NAC) in patients with ovarian cancer (OC) or primary peritoneal serous carcinoma (PPSC) that underwent interval debulking surgery (IOC). MATERIAL AND METHODS: Thirty one patients with advanced OC or PPSC (FIGO stage IIIC and IV) who underwent initial exploratory surgery, followed by NAC containing platinum analogs, have been analyzed, retrospectively. We have used a regression coefficient (RCA 125), which was calculated as following: log10 (CA 125 level measured after two cycles of NAC/baseline CA 125) for statistical analysis. The median value of RCA 125 reached -0.788 and has been used to dichotomize. Optimal IOC has been performed in 67.74% (21/31) patients, suboptimal in 25.81% (8/31) patients and 6.45% (2/31) of patients did not undergo IOC due to the progression of the disease. RESULTS: We have noted significant correspondence between time to progression and RCA 125 in univariate analysis, which we have also confirmed in multivariate analysis (HR 0.27; 95% CI, 0.15-0.96; p = 0.0178). Similarly, we have observed significant relationship between overall survival, RCA 125 and extension IOC in univariate analysis. Multivariate analysis confirmed that RCA 125 was independent prognostic factor, HR-0.18 (95% CI, 0.07-0.56; p = 0.004). In case of patients with high RCA 125, a greater rate of optimal debulking cytoreduction (p = 0.0278, U = 50.0) has been observed. CONCLUSIONS: RCA 125 after two courses of NAC appears to be an important prognostic factor in patients with OC or PPSC, who underwent IOC High RCA 125 during NAC seems to be a good predictive factor in order to achieve optimal IOC. 相似文献
48.
Endometriosis is the most common cause of chronic pelvic pain in adolescent girls (50-70%), unresponsive to treatment of oral contraceptives and non-steroidal anti-inflammatory drugs. The most common symptoms of the disease are: acquired or progressive dysmenorrhea, acyclic and cyclic pain, dyspareunia (in sexually active girls), urological symptoms and gastrointestinal complaints. When evaluating an adolescent with suspected endometriosis, a gynecological examination (rectal or vaginal examination) and imaging studies (ultrasonography, magnetic resonance) should be performed. Moreover, in diagnostic process laparoscopy should be carried out in all girls and teenagers with chronic pelvic pain unresponsive to medical treatment. Initial therapy of endometriosis in adolescent girls involves: surgical methods (laparoscopy/laparotomy), hormonal pharmacotherapy (combined contraceptives, progestin-only protocols), GnRH agonists (adolescents over 16 years of age), non-steroidal anti-inflammatory drugs, alternative pain therapies and psychotherapy. Early diagnosis and treatment during adolescence may decrease disease progression and prevent subsequent infertility. 相似文献
49.
Gmyrek GB Sieradzka U Goluda M Gabryś M Sozański R Jerzak M Zbyryt I Chrobak A Chełmońska-Soyta A 《European journal of obstetrics, gynecology, and reproductive biology》2008,137(1):67-76
OBJECTIVE: The pathogenesis of endometriosis is related to functional changes in CD3+ and CD14+ cells observed both at the local and systemic level. Here we investigated whether, and if so, how the body compartment influences cytokine expression in stimulated peritoneal and peripheral CD3+ and CD14+ cells of women with endometriosis. STUDY DESIGN: Isolated peripheral blood (PB) and peritoneal fluid (PF) mononuclear cells from women with endometriosis were cultured under non-adherent conditions and stimulated with PMA and ionomycin for 6h to induce intracellular cytokine synthesis of TNF-alpha, IFN-gamma, and IL-8 by CD3+ cells or with LPS for 9h to produce TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 by CD14+ cells. RESULTS: The percentages of positive CD3+ cells stained for TNF-alpha and IFN-gamma were significantly higher and those stained for IL-8 were significantly lower in PF compared with PB, this being independent of the stage of endometriosis. In contrast, the percentages of CD14+ cells producing TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 were significantly higher in PB than PF of women with endometriosis. CONCLUSIONS: Monocytes/macrophages and lymphocytes derived from the peripheral and peritoneal compartments of women with endometriosis differentially respond to stimulated cytokine synthesis induction. However, it is difficult to state whether the observed phenomenon is more related to body compartment influence per se or to the presence of endometriosis. 相似文献
50.
This article reviews the current literature of mediastinal tumors as the cause of nonimmune hydrops fetalis (NIHF), the outcomes of reported cases, and a general overview of NIHF including diagnosis, workup, and a management algorithm, with particular attention made to intrathoracic lesions and gestation age. We present a unique case report of a premature neonate who initially presented with NIHF at birth and was subsequently diagnosed with a germ cell mediastinal teratoma as the etiology of NIHF. The patient survived for 50 days while having undergone surgical resection and chemotherapy during the hospital course. The patient represents the first reported case of a mediastinal tumor as the etiology of NIHF in the neonatal period and only one of three cases that have been reported to survive in the neonatal period. Survival is dependent on the thoracic lesion's size, location, resectability, impact on the growth and development of other vital organs, and in the case of tumors, malignant potential. Though the combination of mediastinal teratoma and NIHF is rare, it should be included in the diagnostic evaluation of a newborn with NIHF. 相似文献