scholarly journals FTIR and UV‒vis study of chemically engineered biomaterial surfaces for protein immobilization

2002 ◽  
Vol 16 (3-4) ◽  
pp. 351-360 ◽  
Author(s):  
Herman Mansur ◽  
Rodrigo Oréfice ◽  
Marivalda Pereira ◽  
Zélia Lobato ◽  
Wander Vasconcelos ◽  
...  

The biomaterials research field has broadened in the last 3 decades, including replacement of diseased or damaged parts, assist in healing, correct and improve functional abnormality, drug delivery systems, immunological kits and biosensors. Proteins play crucial role in almost every biological system. They are involved in enzymatic catalysis, transport and storage, coordinated motion, mechanical support, immune protection, control of growth and cell differentiation among many others. The immobilization of proteins onto surface functionalized substrates has been one of the most promising areas in bioengineering field. It is important to note that the term immobilization can refer either to a temporary or to a permanent localization of the biomolecule on or within a support. Proteins have very particular chain configurations and conformations that promote high levels of specificity during chemical interactions. In the present work, we aimed to study the phenomenon of protein immobilization onto biomaterial with chemically engineered surface. We have tailored the surface of the porous gels of SiO2with 5 different silane surface modifying agents: tetraethoxysilane (TEOS), 3‒mercaptopropyltrimethoxysilane (MPTMS) and 3‒aminopropyltriethoxysilane (APTES), 3‒glycidoxypropyltrimethoxysilane (GPTMS) and 3‒isocyanatopropyltriethoxysilane (ICPES). Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the presence of all specific chemical groups in the materials. The surface functionalized gels were then immersed in porcine insulin (PI) solutions for protein immobilization. The incorporation of protein within the gels was also monitored by FTIR spectroscopy. The kinetics of protein adsorption and desorption from the gel matrixin vitrotests were monitored by UV‒visible spectroscopy. We could not observe any evidence of denaturation of insulin after its desorption from gel matrices using UV‒visible spectroscopy technique.In vivotests with adult male rats were used to verify the immobilized insulin bioactivity after implantation of different biomaterial with functionalized surfaces. Plasma glucose levels were obtained by using the Glucose GOD‒ANA Colorimetric Assay. All surface modified materials have presented acute hypoglycemic peak response associated with the insulin bioactivity.

Author(s):  
Guru Kumar Dugganaboyana ◽  
Chethankumar Mukunda ◽  
Suresh Darshini Inakanally

In recent years, green nanotechnology-based approaches using plant materials have been accepted as an environmentally friendly and cost-effective approach with various biomedical applications. In the current study, AgNPs were synthesized using the seed extract of the Eugenia uniflora L. (E.uniflora). Characterization was done using UV-Visible spectroscopy, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analyses. The formation of AgNPs has confirmed through UV-Visible spectroscopy (at 466 nm) by the change of color owing to surface Plasmon resonance. Based on the XRD pattern, the crystalline property of AgNPs was established. The functional group existing in seed of E.uniflora extract accountable for the reduction of Ag+ ion and the stabilization of AgNPs was investigated. The morphological structures and elemental composition was determined by SEM and EDX analysis. With the growing application of AgNPs in biomedical perspectives, the biosynthesized AgNPs were evaluated for their antibacterial and along with their antidiabetic potential. The results showed that AgNPs are extremely effective with potent antidiabetic potential at a very low concentration. It also exhibited potential antibacterial activity against the three tested human pathogenic bacteria. Overall, the results highlight the effectiveness and potential applications of AgNPs in biomedical fields such as in the treatment of acute illnesses as well as in drug formulation for treating various diseases such as cancer and diabetes. It could be concluded that E. uniflora seed extract AgNPs can be used efficiently for in vitro evaluation of their antibacterial and antidiabetic effects with potent biomedical applications.


2020 ◽  
Vol 18 (1) ◽  
pp. 764-777
Author(s):  
Sumaira Naz ◽  
Muhammad Zahoor ◽  
Muhammad Naveed Umar ◽  
Saad Alghamdi ◽  
Muhammad Umar Khayam Sahibzada ◽  
...  

AbstractThioureas and their derivatives are organosulfur compounds having applications in numerous fields such as organic synthesis and pharmaceutical industries. Symmetric thiourea derivatives were synthesized by the reaction of various anilines with CS2. The synthesized compounds were characterized using the UV-visible and nuclear magnetic resonance (NMR) spectroscopic techniques. The compounds were screened for in vitro inhibition of α-amylase, α-glucosidase, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes and for their antibacterial and antioxidant potentials. These compounds were fed to Swiss male albino mice to evaluate their toxicological effects and potential to inhibit glucose-6-phosphatase (G6Pase) inhibition. The antibacterial studies revealed that compound 4 was more active against the selected bacterial strains. Compound 1 was more active against 2,2-diphenyl-1-picrylhydrazyl and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals, AChE, BuChE, and α-glucosidase. Compound 2 was more potent against α-amylase and G6Pase. Toxicity studies showed that compound 4 is safe as it exerted no toxic effect on any of the hematological and biochemical parameters or on liver histology of the experimental animals at any studied dose rate. The synthesized compounds showed promising antibacterial and antioxidant potential and were very active (both in vitro and in vivo) against G6Pase and moderately active against the other selected enzymes used in this study.


2021 ◽  
Vol 30 ◽  
pp. 096368972110354
Author(s):  
Eun-Jung Yoon ◽  
Hye Rim Seong ◽  
Jangbeen Kyung ◽  
Dajeong Kim ◽  
Sangryong Park ◽  
...  

Stamina-enhancing effects of human adipose derived stem cells (hADSCs) were investigated in young Sprague-Dawley rats. Ten-day-old male rats were transplanted intravenously (IV) or intracerebroventricularly (ICV) with hADSCs (1 × 106 cells/rat), and physical activity was measured by locomotor activity and rota-rod performance at post-natal day (PND) 14, 20, 30, and 40, as well as a forced swimming test at PND 41. hADSCs injection increased the moving time in locomotor activity, the latency in rota-rod performance, and the maximum swimming time. For the improvement of physical activity, ICV transplantation was superior to IV injection. In biochemical analyses, ICV transplantation of hADSCs markedly reduced serum creatine phosphokinase, lactate dehydrogenase, alanine transaminase, and muscular lipid peroxidation, the markers for muscular and hepatic injuries, despite the reduction in muscular glycogen and serum triglycerides as energy sources. Notably, hADSCs secreted brain-derived neurotrophic factor (BDNF) and nerve growth factor in vitro, and increased the level of BDNF in the brain and muscles in vivo. The results indicate that hADSCs enhance physical activity including stamina not only by attenuating tissue injury, but also by strengthening the muscles via production of BDNF.


1985 ◽  
Vol 249 (3) ◽  
pp. E276-E280 ◽  
Author(s):  
W. S. Evans ◽  
R. J. Krieg ◽  
E. R. Limber ◽  
D. L. Kaiser ◽  
M. O. Thorner

The effects of gender and the gonadal hormone environment on basal and stimulated growth hormone (GH) release by dispersed and continuously perifused rat anterior pituitary cells were examined. Cells from intact male and diestrus day 2 female rats and from castrate male rats either untreated or treated with testosterone (T) or 17 beta-estradiol (E2) were used. Basal GH release (ng/min per 10(7) cells; mean +/- SE) by cells from diestrus day 2 female rats was less than by cells from castrate rats treated with T (4.3 +/- 0.6 vs. 11.4 +/- 2.7, respectively; P less than 0.025). No other differences in basal release were detected. Concentration-response relationships were documented between human GH-releasing factor 40 (hGRF-40; 0.03-100 nM given as 2.5-min pulses every 27.5 min) and GH release. Mean (+/- SE) overall GH release (ng/min per 10(7) cells) above base line was greater by cells from intact male rats (496 +/- 92) than by cells from castrate (203 +/- 37.3; P less than 0.0001), castrate and T-treated (348 +/- 52.8; P = 0.008), or castrate and E2-treated (58.1 +/- 6.8; P less than 0.001) male rats or by diestrus day 2 rats (68.6 +/- 9.5; P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


1994 ◽  
Vol 59 (1) ◽  
pp. 57-62 ◽  
Author(s):  
Graciela S. Díaz-Torga ◽  
Damasia Becú-Villalobos ◽  
Carlos Libertun

2009 ◽  
Vol 2009 ◽  
pp. 1-13 ◽  
Author(s):  
M. K. Gill-Sharma

In the last 20 years, a pituitary-hypothalamus tissue culture system with intact neural and portal connections has been developed in our lab and used to understand the feedback mechanisms that regulate the secretions of adenohypophyseal hormones and fertility of male rats. In the last decade, several in vivo rat models have also been developed in our lab with a view to substantiate the in vitro findings, in order to delineate the role of pituitary hormones in the regulation of fertility of male rats. These studies have relied on both surgical and pharmacological interventions to modulate the secretions of gonadotropins and testosterone. The interrelationship between the circadian release of reproductive hormones has also been ascertained in normal men. Our studies suggest that testosterone regulates the secretion of prolactin through a long feedback mechanism, which appears to have been conserved from rats to humans. These studies have filled in a major lacuna pertaining to the role of prolactin in male reproductive physiology by demonstrating the interdependence between testosterone and prolactin. Systemic levels of prolactin play a deterministic role in the mechanism of chromatin condensation during spermiogenesis.


Reproduction ◽  
2021 ◽  
Author(s):  
Marina Izvolskaia ◽  
Vasilina Ignatiuk ◽  
Ayshat Ismailova ◽  
Viktoria Sharova ◽  
Liudmila Zakharova

Sexual performance in adult male rats is highly sensitive to prenatal stress which can affect the functionality of the reproductive system and various brain structures involved in modulating sexual behavior. The immunomodulatory effect of mouse IgG on reproductive maturity in male offspring after LPS exposure in vivo and in vitro was studied. Prenatal IgG injection (20 µg / mouse) had a positive impact on the puberty of male mice whose mothers were exposed to LPS (100 µg / kg) on the 12th day of pregnancy. The number of Sertoli cells were increased, whereas the body weight and the number of symplastic spermatids were decreased in offspring as compared to LPS-treated animals. Besides, IgG had a positive effect on altered hormone levels: reduced estradiol level on the 5th and 14th postnatal days and increased testosterone level on the 30th postnatal day in blood that led to an increased number of mounting attempts in sexually mature males. The cAMP-dependent pathway may be involved in the regulation of the LPS-induced inflammation. IgG reduced the increased level of cAMP in mouse peritoneal macrophages activated by LPS in vitro. IgG is able to modulate inflammation processes, but its exposure time is important.


2013 ◽  
Vol 49 (4) ◽  
pp. 803-809
Author(s):  
Monica Lacerda Lopes Martins ◽  
Henrique Poltronieri Pacheco ◽  
Iara Giuberti Perini ◽  
Dominik Lenz ◽  
Tadeu Uggere de Andrade ◽  
...  

In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES), a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE) activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE) and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg), with acetylcholine (ACh) as positive control (5 µg/kg, i.v.). The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg) in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.). Captopril (30 mg/kg) was used as positive control. Bulbostylis capillaris (86.89 ± 15.20%) and ERE (74.89 ± 11.95%, ERE) were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%). ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.


Author(s):  
Adetutu Adewale ◽  
Olaniyi Deborah Temitope ◽  
Awodugba Tamilore ◽  
Owoade Abiodun Olusoji ◽  
Olaniyan, Lamidi Waheed B. ◽  
...  

Typhoidal salmonella infections remain a challenge in the health care system in sub-Saharan Africa. Carrier status and advent of multi-drug resistant S. Typhi strains have necessitated the search for new drug leads. Hence, this study aims at investigating P. guajava and A. indica leaves for anti-salmonella activities. Guava and neem leaves were extracted by maceration in methanol and fractionated by solvent partitioning. In vitro activities were assessed by agar well diffusion and broth micro-dilution methods. Sixty male rats were randomized to 10 groups of 6 animals each for the in vivo experiments. Groups of rats except, normal control, were induced with 0.5McFarland of S. Typhi suspension orally. Treatment groups received 200 mg/kg body weight of extracts and fractions, and the control groups were treated with 14.29mg/kg body weight of ciprofloxacin and 1%v/v DMSO for 7 days post-infection. Biochemical parameters were determined spectrophotometrically. Hematological parameters were analyzed with automated hematology diagnostic machine. All fractions of P. guajava and three of A. indica inhibited S. Typhi growth with Zone of Inhibition (ZI) ranging from 11-15 mm. Active fractions inhibited 48.60-62.45% of S. Typhi biofilm formation at 25 mg/mL with Minimum Bactericidal Inhibitory Concentration (MBIC) of 0.39-12.5 mg/mL. All fractions improved body weight of treated rats and inhibited bacteremia at 44.75 and 95.94%. Hematological parameters improved in all fractions-treated rats. MDA was not significantly (p<0.05) altered in all groups. One fraction of P. guajava (ePg) lowered the elevated level in concentration of Nitric oxide (NO) while all fractions enhanced the lowered activity of SOD. Elevated (lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and bilirubin (BIL) were lowered by all fractions to various extents in treated rats. Fractions of P. guajava, and A. indica could be further considered for identification of active anti-salmonella principle(s).


Sign in / Sign up

Export Citation Format

Share Document