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1.
Cryo Letters ; 45(5): 309-319, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39126333

RESUMO

BACKGROUND: Various antioxidant substances are added to sperm extenders to protect spermatozoa against oxidative stress and cryodamage. OBJECTIVE: To investigate the effects of the flavonoid diosmin (DIO) and a flavanone glycoside naringin (NAR) on the freezability of ram semen. MATERIALS AND METHODS: In this study, six Merino rams were used during the breeding season. The ejaculates were pooled after collection from the rams. Pooled ejaculates were divided into six groups: control, NAR 1 mM, NAR 2 mM, NAR 4 mM, DIO 2 mM, and DIO 4 mM, and then diluted with a TRIS-based diluent. The pooled semen was equilibrated, placed in 0.25 mL pipettes with 10 × 10 7 sperm cells in each pipette, and frozen in liquid nitrogen vapor. After 24 h, the pipettes were thawed at 37 degree C for 25 s and analyzed in terms of spermatological parameters. RESULTS: The highest plasma membrane integrity ratio was found in the DIO 4 mM group, whereas a statistically significant difference was found between the NAR 1 mM and NAR 2 mM groups (p < 0.05). While the DIO 4 mM group had the highest acrosome integrity rate, a statistically significant difference was found between the other groups (p < 0.05). Mitochondrial activity was the highest in the NAR 4 mM, DIO 4 mM and DIO 2 mM groups (p < 0.05). In the analysis of the sperm membrane lipid profile, it was observed that the DIO group had the highest lipid-phospholipid ratio. In sperm membrane protein profile analysis, it was found that both additives exerted protective effects at different levels. The highest total protein content was seen in the DIO 4 mM and NAR 4 mM groups. 8-hydroxydeoxyguanosine (8-OhDG) positivity was more common in the control group than in the DIO and NAR groups. Cu-Zn superoxide dismutase (SOD) expression was lower in the control group and more intense in all other groups. Positive results were especially observed in the acrosome of the sperm cells. CONCLUSION: The addition of NAR and DIO to the ram semen extender increased the quality of sperm parameters after the freeze-thaw process. Doi.org/10.54680/fr24510110412.


Assuntos
Criopreservação , Diosmina , Flavanonas , Preservação do Sêmen , Espermatozoides , Masculino , Animais , Diosmina/farmacologia , Ovinos , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Flavanonas/farmacologia , Criopreservação/métodos , Criopreservação/veterinária , Espermatozoides/efeitos dos fármacos , Sêmen/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Antioxidantes/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Crioprotetores/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Análise do Sêmen , Superóxido Dismutase/metabolismo
2.
Arch Biochem Biophys ; 733: 109481, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36522815

RESUMO

Ruscogenin, a kind of steroid saponin, has been shown to have significant anti-oxidant, anti-inflammatory, and anti-thrombotic characteristics. Furthermore, it has the potential to be employed as a medicinal medication to treat a variety of acute and chronic disorders. The interaction of a drug molecule with cell membranes can help to elucidate its system-wide protective and therapeutic effects, and it's also important for its pharmacological activity. The molecular mechanism by which ruscogenin affects membrane architecture is still a mystery. Ruscogenin's interaction with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) and anionic dipalmitoyl phosphatidylglycerol (DPPG) multilamellar vesicles (MLVs) was studied utilizing two non-invasive approaches, including: Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry. Ruscogenin caused considerable alterations in the phase transition profile, order, dynamics and hydration state of head groups and glycerol backbone of DPPC and DPPG MLVs at all concentrations. The DSC results indicated that the presence of ruscogenin decreased the main phase transition temperature (Tm) and enthalpy (ΔH) values of both membranes and increased half height width of the main transition (ΔT1/2). The FTIR results demonstrated that all concentrations (1, 3, 6, 9, 15, 24 and 30 mol percent) of ruscogenin disordered the DPPC MLVs both in the gel and liquid crystalline phases while it increased the order of DPPG MLVs in the liquid crystalline phase. Moreover, ruscogenin caused an increase in the dynamics of DPPC and DPPG MLVs in both phases. Additionally, it enhanced the hydration of the head groups of lipids and the surrounding water molecules implying ruscogenin to interact strongly with both zwitterionic and charged model membranes.


Assuntos
1,2-Dipalmitoilfosfatidilcolina , Fluidez de Membrana , 1,2-Dipalmitoilfosfatidilcolina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Fourier , Fosfatidilgliceróis/química , Varredura Diferencial de Calorimetria , Bicamadas Lipídicas/química
3.
Int J Paediatr Dent ; 32(5): 756-763, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35102638

RESUMO

BACKGROUND: Prefabricated fibreglass crowns (PFCs) require less tooth structure reduction than prefabricated zirconium crowns (PZCs) for restoring primary molars. Little is known, however, about their mechanical properties. AIM: To investigate the fatigue survival and fracture resistance of PZCs and PFCs cemented with two different types of luting cement [glass-ionomer cement (GIC) and resin-modified GIC (RMGIC)]. DESIGN: One hundred and twenty extracted human primary molars were randomly divided into subgroups (n = 15) according to the crown type (PFCs/PZCs), the luting cement (GIC/RMGIC) and crowns subjected to the chewing simulation test with thermocycling mechanical loading (CSTTML). The surfaces of the teeth were reduced by approximately 2 mm in the PZC group and 1 mm in the PFC group. All the samples were subjected to fracture tests. RESULTS: None of the samples subjected to CSTTML exhibited signs of surface damage, fracture or premature debonding. The forces required to fracture PFCs were higher than those required for PZCs in all groups (p = .001). The highest mean fracture resistance values were obtained from the group of PFCs cemented with GIC that were subjected to the CSTTML (2515.8 N ± 619.2 N). CONCLUSIONS: PFCs presented high fatigue survival and could be used as alternatives to PZCs as they require less tooth structure reduction. Crowns cemented with GIC had a similar fracture resistance value when compared with RMGIC.


Assuntos
Cimentos de Resina , Zircônio , Cimentação , Coroas , Cimentos Dentários/química , Materiais Dentários/química , Análise do Estresse Dentário , Vidro , Cimentos de Ionômeros de Vidro/química , Humanos , Teste de Materiais , Cimentos de Resina/química
4.
Environ Monit Assess ; 192(1): 61, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31865447

RESUMO

Tellurium has been widely used in industrial processes and daily life products, and can cause serious health problems upon exposure. Therefore, determination of tellurium in real-life samples is very crucial. In this study, an accurate, environmentally friendly, and inexpensive analytical method was developed to determine trace levels of tellurium in water samples. To lower the detection limits, system parameters including flame type, acetylene flow rate, slotted quartz tube (T-SQT) height, and trapping period were optimized. Under the optimum conditions, the limit of detection (LOD) and quantification (LOQ) were calculated as 14.1 ng/mL and 47.1 ng/mL, respectively. For recovery studies, the optimized T-SQT-AT-FAAS method was applied to tap water samples to determine trace levels of tellurium and recovery results were found between 91.1 and 111.3%. Relative standard deviation value (%RSD) of the developed method was found to be less than 5.0% even for the lowest concentration in calibration plot, specifying good accuracy and high applicability of the method for water samples. Graphical abstract .


Assuntos
Água Potável/química , Monitoramento Ambiental/métodos , Espectrofotometria Atômica/métodos , Telúrio/análise , Poluentes Químicos da Água/análise , Água Potável/normas , Monitoramento Ambiental/instrumentação , Concentração de Íons de Hidrogênio , Limite de Detecção , Microextração em Fase Líquida/métodos
5.
Biochim Biophys Acta Biomembr ; 1862(6): 183245, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113848

RESUMO

Levothyroxine (3,5,3',5'-tetraiodothyronine), which is a L-isomer of thyroxine T4 (L-T4), is a synthetic thyroid hormone that is biochemically and physiologically indistinguishable from endogenous T4. It is used as a thyroid hormone replacement drug to treat an underactive thyroid gland. The interaction of L-T4, with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) was studied in the presence (1 mol%, 3 mol%, 6 mol%, 9 mol%, 15 mol%, 24 mol% and 30 mol%) and absence of L-T4 by using two different non-invasive techniques; Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC). The results show that L-T4 does perturb the phase transition profile by either decreasing the main transition temperature (Tm) and enthalpy (ΔH) or increasing the width at half height (ΔT½). That means; it changes the physical properties of DPPC bilayers. Addition of L-T4 into pure DPPC liposomes shifts the phase transition to lower temperature, disorder the system in gel phase with opposite effect in liquid-crystalline phase and increases the dynamics of the system in both phases and also causes dehydration of the groups of lipids and the water molecules around.


Assuntos
1,2-Dipalmitoilfosfatidilcolina , Lipossomos/química , Tiroxina/farmacologia , Varredura Diferencial de Calorimetria , Relação Dose-Resposta a Droga , Transição de Fase/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica , Água
6.
Pediatr Dent ; 40(7): 443-448, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31840645

RESUMO

Purpose: The purpose of this study was to determine the retention of prefabricated primary zirconium crowns (PPZCs) and the fracture resistance of samples cemented with four different luting cements subjected to a chewing simulation test with thermocycling mechanical loading (CSTTML). Methods: A total of 120 extracted primary molar teeth were selected and allocated into four groups, according to luting cement materials (bioactive cement, resin cement, glass ionomer cements [GICs], resin-modified GICs). After half of each group was subjected to CSTTML, all the samples were subjected to fracture tests and the mean force required to fracture the PPZCs was recorded. Results: After the CSTTML test, corresponding to a simulated one-year aging, none of the sample materials were found to be cracked, fractured, chipped, or non-retained. Resin cements in all groups showed the highest fracture resistance, whereas bioactive cement, subjected to CSTTML and resin-modified GIC in all tests, showed the lowest values. However, no statistically significant differences were found. Conclusions: The prefabricated primary zirconium crowns were found to be successful after almost one year of simulated aging. The results of all of groups showed that the PPZCs cemented with resin and glass ionomer cements were more successful. However, further in vitro and in vivo studies are needed to determine their potential for clinical success.


Assuntos
Cimentação , Zircônio , Coroas , Cimentos Dentários , Análise do Estresse Dentário , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos de Resina
7.
Biochim Biophys Acta ; 1668(2): 215-22, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15737332

RESUMO

Interactions of melatonin with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of temperature and melatonin concentration (1-30 mol%) by using two noninvasive techniques, namely Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The investigation of the C-H, CO, and PO2- antisymmetric double stretching modes in FTIR spectra and DSC studies reveal that melatonin changes the physical properties of the DPPC bilayers by decreasing the main phase transition temperature, abolishing the pretransition, ordering the system in the gel phase, and increasing the dynamics of the system both in the gel and liquid crystalline phases. It also causes significant decrease in the wavenumber for the CO stretching and PO2- antisymmetric double bond stretching bands, which indicates strong hydrogen bonding The results imply that melatonin locates in the interfacial region of the membrane. Furthermore, in the DSC curve, more than one signal is observed at high melatonin concentrations (24 and 30 mol%), which indicates melatonin-induced phase separation in DPPC membranes.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Lipossomos/química , Melatonina/química , Varredura Diferencial de Calorimetria , Membranas Artificiais , Conformação Molecular , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
8.
Chem Phys Lipids ; 188: 37-45, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25847673

RESUMO

Desmosterol is a direct biosynthetic precursor of cholesterol in Bloch biochemical pathway of cholesterol biosynthesis and differs with cholesterol only by a double bond in carbon 24. In this study, we aimed to research for the first time comparative effects of cholesterol and its precursor desmosterol on dipalmitoyl phosphatidylcholine (DPPC) multilamellar vesicles (MLVs) by utilizing Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Our DSC studies reveal that with the addition of increasing desmosterol and cholesterol concentrations into pure DPPC MLVs, the pretransition disappears, the main phase transition shifts to lower temperatures and then disappears. While the main phase transition is abolished at 25 mol% concentration of desmosterol, this disappearance of the main phase transition occurs at cholesterol concentration above 30 mol%. Our FTIR studies show that both desmosterol and cholesterol decrease the order in the gel phase, whereas they increase it in the liquid crystalline phase. Importantly, we found that the effect of desmosterol on membrane order is weaker than that of cholesterol in both phases. Moreover, desmosterol and cholesterol increase the dynamics of DPPC membranes in the gel phase, while they decrease it in the liquid crystalline phase. Both sterols also induce a decrease in the wavenumber values of the C=O stretching and PO2(-) antisymmetric double stretching bands of DPPC both in the gel and liquid crystalline phases, which points out hydrogen bonding in between the hydroxyl group of both sterols and the carbonyl and phosphate groups of DPPC membranes.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Colesterol/química , Desmosterol/química , Bicamadas Lipídicas/química , Modelos Moleculares , Estrutura Molecular , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
9.
Artigo em Inglês | MEDLINE | ID: mdl-24792199

RESUMO

Interactions of a non-steroidal antiestrogen drug, tamoxifen (TAM), with distearoyl-sn-glycero-3-phosphatidylcholine (DSPC) multilamellar liposomes (MLVs) were investigated as a function of drug concentration (1-15 mol%) by using two noninvasive techniques, namely Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). FTIR spectroscopy results show that increasing TAM concentrations (except 1 mol%) increased the wavenumbers of the CH2 stretching modes, implying an disordering effect for DSPC MLVs both in the gel and liquid crystalline phases. The bandwidth values of the CH2 stretchings except for 1 mol% increased when TAM concentrations increased for DSPC liposomes, indicating an increase in the dynamics of liposomes. The CO stretching and PO2- antisymmetric double bond stretching bands were analyzed to study interactions of TAM with head groups of lipids. As the concentrations of TAM increased, dehydration occurred around these functional groups in the polar part of the lipids. The DSC studies on thermal properties of DSPC lipids indicate that TAM eliminated the pre transition, shifted the main phase transition to lower temperatures and broadened the phase transition curve of the liposomes.


Assuntos
Varredura Diferencial de Calorimetria , Fosfatidilcolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tamoxifeno/química , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Lipídeos/química , Lipossomos/química , Membranas Artificiais , Neoplasias/patologia , Temperatura
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