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1.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003339

RESUMO

Sapogenins are the non-sugar parts of saponins (aglycones), high-molecular-weight glycosides linked to one or more sugar side chains. This group of compounds presents many properties, e.g., the potent properties of reducing surface tension and foaming properties, as evidenced by the amphipathic nature of these substances. They are used in the cosmetics industry, the washing and detergent industry, and the food industry. In addition, they have many healing properties. They lower blood cholesterol but are also used to synthesize steroid drugs or hormones. As reported in the literature, saponins also show antitumor activity, leading to cell cycle inhibition and apoptosis of various neoplastic cells. In this study, the influence of two sapogenins: asiatic acid (AA) and oleanolic acid (OA), on the properties of monolayers made of phosphatidylcholine (DPPC) was investigated. The method used in these studies was the Langmuir method with Brewster angle microscopy. The interactions between the tested compounds in mixed monolayers were described. Using mathematical equations, we established that oleanolic acid and asiatic acid formed complexes with DPPC at 1:1 ratios, characterized by high stability constants. We derived the parameters characterizing the formed complexes and described the phase transitions that occur during the formation of pure and mixed monolayers.


Assuntos
Ácido Oleanólico , Sapogeninas , Saponinas , Triterpenos , Água/química , Lecitinas , Propriedades de Superfície , 1,2-Dipalmitoilfosfatidilcolina/química
2.
Ann Med Surg (Lond) ; 67: 102483, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34168874

RESUMO

INTRODUCTION AND IMPORTANCE: Primary intestinal lymphangiectasia (PIL) is a rare protein-losing gastroenteropathy of unknown etiology, characterized by impaired lymphatic vessels drainage. The pathological changes in PIL result in usually localized or diffuse dilatation of intestinal lacteals, leading to leakage of lymphatic fluid rich of proteins, lymphocytes, and immunoglobulins into the intestinal lumen. PIL may be asymptomatic or mildly symptomatic in moderate forms of the disease. In some patients, though, the outcome may be poor or even life-threatening. This case report demonstrates the severity of protein malnutrition, in some cases, and the extent of GI tract affected, requiring to start PN early and the need for its continuation as home parenteral nutrition (HPN). CASE PRESENTATION: We present a case of 39-year-old male with Factor V Leiden deficiency, who presented initially with symptoms of malnutrition and anasarca. The diagnosis was confirmed by histopathological findings pathognomonic for PIL from biopsies of the stomach, small intestine and colon. CLINICAL DISCUSSION: The patient was started on low fat, high protein parenteral nutrition from the beginning of the treatment and required a long-term HPN for 3 years, because trials of tapering off and discontinuation of PN led to worsening of the biochemical results and recurrence of symptoms. Patient gradually improved and stabilized with persistent nutritional support. CONCLUSIONS: The presented case report shows the magnitude of nutritional support (HPN) needed for severe PIL patients. HPN offers PIL patients with poor outcome and life-threatening complications a chance to improve and lead a normal life.

3.
J Phys Chem B ; 124(6): 1104-1114, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-31972080

RESUMO

In this study, 25-hydroxycholesterol (25-OH), a biamphiphilic compound with a wide range of biological activities, has been investigated at the air/water interface. We were interested in how two hydroxyl groups attached at distal positions of the 25-OH molecule (namely, at C(3) in the sterane system and at C(25) in the side chain) influence its surface behavior. Apart from traditional Langmuir monolayers, other complementary surface-sensitive techniques, such as electric surface potential measurements, Brewster angle microscopy (BAM, enabling texture visualization and film thickness measurements), and polarization modulation-infrared reflection-absorption spectroscopy (PM-IRRAS), were applied. Experimental data have been interpreted with the aid of theoretical study. Our results show that 25-OH molecules in the monomolecular layer are anchored to the water surface alternatively with C(3) or C(25) hydroxyl groups. Theoretical calculations revealed that the populations of these alternative orientations were not equal and molecules anchored with C(3) hydroxyl groups were found to be in excess. As a consequence of such an arrangement, surface films of 25-OH are of lower stability as compared to cholesterol (considered as a non-oxidized analogue of 25-OH). Moreover, it was found that, upon compression, the transition from mono- to bilayer occurred. The molecular mechanism and interactions stabilizing bilayer structure were proposed. The explanation of the observed unusual surface behavior of 25-OH may contribute to an understanding of differences in biological activity between chain- and ring-oxidized sterols.


Assuntos
Teoria da Densidade Funcional , Ar , Hidroxicolesteróis , Estrutura Molecular , Tamanho da Partícula , Espectrofotometria Infravermelho , Propriedades de Superfície , Água/química
4.
Biophys Chem ; 258: 106318, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31918024

RESUMO

Among numerous compounds found in marine organisms, astaxathin has received considerable research interest due to beneficial impact on health such as anti-inflammatory, antioxidant and neuroprotective activity. Recently new functionalities of this xanthophyll have been revealed indicating important applications in nutrition and pharmacy. However, astaxanthin, as the bioactive, has limited value without a protecting carrier that provides controlled release in a human body. Fabrication of liposomes as efficient drug delivery systems is promising strategy that may overcome these problems. However, the development of new delivery systems requires comprehensive understanding of physicochemical properties of carotenoids and their carriers as well as the interactions between them. The aim of this study was to investigate the mixed lipid-sterol monolayer in the presence of astaxanthin in terms of thermodynamic, morphological and viscoelastic behaviour. The results have been discussed in relation to pure lipid-sterol films. In addition we determined the surface charge density of the liposomes built of these components. The results are helpful in better understanding the role of interfacial viscoelasticity in the quality of liposomal drug delivery forms.


Assuntos
Lipídeos de Membrana/química , Termodinâmica , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Sistemas de Liberação de Medicamentos , Eletricidade , Humanos , Lipossomos/química , Fármacos Neuroprotetores/química , Viscosidade , Xantofilas/química
5.
Nutrition ; 38: 28-33, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28526379

RESUMO

OBJECTIVE: Teduglutide is an active, glucagon-like peptide (GLP)-2 analog with proven clinical efficacy regarding intestinal adaptation in patients with short bowel syndrome (SBS). There are two factors that preclude its reimbursement, and thereby, its availability: its cost (reaching ∼$300,000/y)-which significantly exceeds the cost of home parenteral nutrition (HPN) in most countries-and the lack of clear guidelines. The aim of this study was to create evidence-based working criteria for the use of teduglutide that could be used in clinical settings. METHODS: Experts from the Polish Network of Intestinal Failure Centers analyzed available research and considered experience on the topic of HPN and intestinal failure to create guidelines. RESULTS: Experts agreed that there are two groups of HPN patients who can benefit from therapy with a GLP-2 analog: those with a good prognosis (in whom complete weaning from HPN may be possible) and those with a poor prognosis (the therapy would be lifesaving). Patient criteria comprise the following: inclusion and exclusion criteria, parameters that can be used for monitoring, outcome measures, and the rationale for the termination of the treatment. CONCLUSIONS: It was possible to describe inclusion criteria for both patient groups that justify the use of teduglutide from medical and economic perspectives.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Peptídeos/uso terapêutico , Síndrome do Intestino Curto/tratamento farmacológico , Humanos , Polônia , Resultado do Tratamento
6.
ChemMedChem ; 11(21): 2398-2409, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27714934

RESUMO

A series of previously unknown sulforaphane analogues with organofluorine substituents bonded to the sulfinyl sulfur atom, an isoselenocyanate moiety in place of the isothiocyanate group, the central sulfur atom in various oxidation states, and different numbers of methylene groups in the central alkyl chain were synthesized and fully characterized. All new compounds were tested for their biological properties in vitro and demonstrated much higher anticancer activity against two breast cancer cell lines than that shown by native sulforaphane; at the same time, the compounds were less toxic for normal cells. The influence of the particular structural changes in the molecules on the cytotoxicity is discussed.

7.
Pol Przegl Chir ; 86(10): 466-72, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25720105

RESUMO

UNLABELLED: Home enteral nutrition (HEN for short) allows practically normal living for patients who cannot be fed orally but at the same time do not have to stay in hospitals, which is often found to decrease their mental condition, increase of probability of complications and costs of medical treatment. The aim of the study was to analyze the frequency of nutritional, mechanical and septic complications in patients fed enterally in home conditions. MATERIAL AND METHODS: The study performed using retrospective analysis of study results and reports from control visits for patients in the period between 2012-2013. 147 patients fed enterally using HEN method participated in the study, including 70 men and 77 women aged 19 to 99 years (average 65 years). The following type of gastrointestinal tract access was used for patients: PEG in 113 (76.5%), feeding jejunostomy - 21 (1.4%), PEG-PEJ - 5 (3.5%), in case of the remaining 8 patients the nasogastric gavage (5.5%) was used. RESULTS: The most common complication were infections (of gastric tract, skin soft tissue in the region of nutritional fistula entry, in three cases the aspiration pneumonia was diagnosed) found in 55 (49.1%) of cases. Mechanical complications were found out in 29 (25.9% of all complications), nutritional complications were present 28 times, which constituted 25% of all complications. CONCLUSIONS: In the studied group of patients with an implemented HEN procedure, septic complications were the most common problem. The longest average nutrition time with PEG-PEJ probably results from the effective protection of the patient against aspiration pneumonia.


Assuntos
Nutrição Enteral/efeitos adversos , Nutrição Enteral/métodos , Assistência Domiciliar/métodos , Intubação Gastrointestinal/efeitos adversos , Pneumonia Aspirativa/etiologia , Sepse/etiologia , Infecção da Ferida Cirúrgica/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Falha de Equipamento , Feminino , Humanos , Jejunostomia , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Estudos Retrospectivos , Adulto Jovem
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