Portland cement used in the construction industry improves its properties when wet. Since most dental materials are used in a moist environment, Portland cement has been developed for use in ...dentistry. The first generation material is mineral trioxide aggregate (MTA), used in surgical procedures, thus in contact with blood. The aim of this study was to compare the setting of MTA in vitro and in vivo in contact with blood by subcutaneous implantation in rats. The tissue reaction to the material was also investigated. ProRoot MTA (Dentsply) was implanted in the subcutaneous tissues of Sprague-Dawley rats in opposite flanks and left in situ for 3 months. Furthermore the material was also stored in physiological solution in vitro. At the end of the incubation time, tissue histology and material characterization were performed. Surface assessment showed the formation of calcium carbonate for both environments. The bismuth was evident in the tissues thus showing heavy element contamination of the animal specimen. The tissue histology showed a chronic inflammatory cell infiltrate associated with the MTA. MTA interacts with the host tissues and causes a chronic inflammatory reaction when implanted subcutaneously. Hydration in vivo proceeds similarly to the in vitro model with some differences particularly in the bismuth oxide leaching patterns.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this paper, the effects of coagulation and temperature on the dielectric properties of human blood are investigated over the frequency range of 400 MHz-20 GHz using freshly extracted blood ...samples. The dielectric properties are measured using blood in four different sample collection tubes (bottles): one containing pure whole blood, two containing different anticoagulant agents, and one containing clot activator and serum separator. The collected data indicates that additive agents can have a significant impact on the measured dielectric properties of blood, both immediately after the sample is taken, and over longer time periods. This is an important finding as it suggests that measurements of blood properties conducted on sample repositories, or tissue banks, may not be representative of natural blood properties. Further, the results demonstrate that the dielectric properties of normal blood vary over time due to coagulation. Different clotting rates lead to dielectric properties of female and male blood samples that vary distinctly over time. The results also show that the relative permittivity of the anti-coagulated blood decreases with increasing temperature, up to the cross-over point around 10 GHz where the trend reverses.
The aim of the present study was to synthesize mixture solutions which can accurately mimic the dielectric properties of biological tissues, specifically muscle and adipose tissues between 500 MHz ...and 50 GHz. Mixtures utilizing concentrations of bovine serum albumin (BSA) dissolved in phosphate buffered saline (PBS) and Ringer's solutions were synthesized to mimic in vivo and ex vivo muscle tissues. Solutions consisting of concentrations of peanut oil and Triton X-100 (TX) in PBS and Ringer's solutions were also synthesized to mimic in vivo and ex vivo adipose tissue. Results were then analysed and compared to measured dielectric properties of in vivo and ex vivo biological tissues from another previous study. Good agreement with said dielectric property measurements were obtained since the solutions from this study yielded low RMSE and RMSRE values. This implied that such solutions can be utilized in the construction of human body phantoms for narrowband and ultra-wideband microwave devices for near field breast cancer imaging.
In this article, we report on the characterization of the dielectric properties of in vivo rat liver at 36.4°C from 500 MHz up to 40 GHz with less than 5% uncertainty. The measured data were fitted ...to a Cole-Cole model and dielectric parameters are presented together with their respective 95% confidence interval. The root mean square error is 0.42. Moreover, ex vivo measurements were conducted in situ at 1, 2, 4 and 6 min after animal death and are compared to in vivo measurements. The results show that immediate changes in
and
are within experimental uncertainty, and therefore changes between in vivo and published ex vivo dielectric properties can be attributed to tissue hydration.
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IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
5.
The role of cytokines in skin aging Borg, M.; Brincat, S.; Camilleri, G. ...
Climacteric : the journal of the International Menopause Society,
10/2013, Volume:
16, Issue:
5
Journal Article
Peer reviewed
Abstract
Cutaneous aging is one of the major noticeable menopausal complications that most women want to fight in their quest for an eternally youthful skin appearance. It may contribute to some ...maladies that occur in aging which, despite not being life-threatening, affect the well-being, psychological state and quality of life of aged women. Skin aging is mainly affected by three factors: chronological aging, decreased levels of estrogen after menopause, and environmental factors. Aged skin is characterized by a decrease in collagen content and skin thickness which result in dry, wrinkled skin that is easily bruised and takes a longer time to heal. Cytokines play a crucial role in the manifestation of these features of old skin. The pro-inflammatory cytokine tumor necrosis factor-alpha inhibits collagen synthesis and enhances collagen degradation by increasing the production of MMP-9. It also lowers the skin immunity and thus increases the risk of cutaneous infections in old age. Deranged levels of several interleukins and interferons also affect the aging process. The high level of CCN1 protein in aged skin gives dermal fibroblasts an 'age-associated secretory phenotype' that causes abnormal homeostasis of skin collagen and leads to the loss of the function and integrity of skin. Further research is required especially to establish the role of cytokines in the treatment of cutaneous aging.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The aim of this study was to characterize the hydration fractions of biological tissues and to model these accurately from mixture equations. Hydration fractions, better known as volume fractions, ...are based on quantification of tissue hydration and accurate knowledge about the physiological composition of tissue fluids. Data on weight loss percentages for excised muscle and adipose tissue from a previous study were utilized for this purpose. The Bruggeman and Maxwell Garnett equations were then used to characterize the dielectric properties of the tissues in terms of mixtures of dry biological constituents and physiological saline solutions. It is shown that these models are accurate in modelling in vivo and ex vivo tissue in different states of hydration. This is based on precise knowledge of the physiological composition of biological fluids and their corresponding percentage contents.
Probiotics (PB) are living microorganisms that act as a commensal population in normal intestines and confer numerous beneficial effects on the host. The introduction of probiotics in the treatment ...of inflammatory bowel disease (IBD) prolongs remission. The aim of this study was to investigate the intestinal and hepatic effects of PB supplementation in an experimental IBD model in mice induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). In the first step of the experimental procedure, CD-1 male mice, 5 to 6 weeks old, were randomly divided into 3 groups and inoculated intrarectally with, respectively, saline, alcohol, or TNBS to assess the experimental IBD model. In the second step, mice treated, or not, with TNBS inoculation, were treated with PB (Lactobacillus Casei, Bifidobacterum Lactis) for 1, 2 or 3 weeks, on a daily basis. Large bowel (colon and rectum) and liver were processed for histological alterations, according to a scoring system. Large bowel was also assessed for apoptosis by TUNEL assay. TNBS induced, as expected, severe damage and inflammation in the large bowel, including nuclear alterations and apoptosis, and, to a lesser extent, to the liver. Administration of PB determined significant reduction of both histological alterations and apoptosis. PB administration in advance protects from inflammation. In conclusion, supplementation with Lactobacillus casei, Bifidobacterum lactis PB is able to ameliorate the colitis by reversing the histological changes caused by TNBS in mice. Experimentation in human subjects in needed to prove their efficacy in reducing histological alterations that may be present in subjects with IBD.
Summary
Malta was under Norman rule for over 400 years and has had three major documented plague outbreaks (and a number of minor ones) since the 14th century with death tolls of 5–15% of the ...population at the time. This makes the Maltese population ideal for testing the hypothesis that the Black Death (particularly that of 1346–52) was responsible for a genetic shift that spread the CCR5‐Δ32 allele. By enrolling 300 blood donors to determine the percentage of the Maltese population resistant to HIV‐1 (which uses the CCR5‐receptor to infect cells), it was established that the CCR5‐Δ32 allele frequency is almost zero in third‐generation Maltese citizens and sequencing showed that the deletion observed in the region of interest is the 32‐base deletion expected. Thus, despite the extensive Norman occupation and the repeated plague cullings, the CCR5‐Δ32 allele frequency is extremely low. This provides a basis for the discussion of conflicting hypotheses regarding the possible origin, function and spread of the CCR5‐Δ32 deletion.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Various studies suggest that increased levels of pro-inflammatory cytokines play a key role in the declining ovarian function and the resulting complications associated with menopause. In this review ...article, the authors outline the role of pro- and anti-inflammatory cytokines in cardiovascular disease during menopause.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The Maltese Islands form a small archipelago in the Mediterranean Sea that have been isolated physically from the closest European and African continents since the late Miocene period when harsh ...tectonic movements resulted in the small landmass. During the ensuing temporal and geographical isolation, flora and fauna have been subjected to intense selection pressure resulting in diversification from the forms found on the mainlands.
In this poster, the results of a study on the anti-inflammatory activity of phenolic products from monocultivar oil extracts derived from two indigenous olive drupe varietals are presented. Polar extracts were isolated from the oil using methanol-water and subsequently dried using rotary evaporation and freeze drying. The total antioxidant activity in the polar polyphenol fractions as well as suitable controls was determined using the Folin-Ciocalteu reagent (Sultana
et al
., 2009) followed by GC analysis. Extracts at test concentrations of 2 ppm and 200 ppm were tested on lipopolysaccharide (LPS) (1 microgram/mL) stimulated human macrophage cells. Cyclooxygenase-2 (COX-2) inhibition was studied using the Cayman enzyme immunoassay-chemical kit.
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