Fabrication of hydroxyapatite-based nano-gold and nano-silver-doped bioceramic bone grafts: Enhanced mechanostructure, cell viability, and nuclear abnormality properties.

In this study, nano-gold (nAu) and nano-silver (nAg) were doped at the molar ratios of Molar5-Molar30 to the Hydroxyapatite (HAp)-based bioceramic bone graft synthesized by the sol-gel method. The effects of nAu and nAg on structural, mechanical, cell viability, and nuclear abnormality of the synthesized bioceramic grafts were evaluated. The chemical and morphological properties of the bone grafts after production were examined through XRD and SEM-EDX analyses and mechanical tests. To determine the biocompatibility of the bone grafts, cell viability tests were performed using human fibroblast cells. In the cytotoxicity analyses, only HAp and HAp-nAu5 grafts did not show toxicological properties at any concentration, while HAp-nAg5 among the nAg-containing grafts gave the best results at the 200-100 µg/mL concentrations and showed significant cytotoxicity in human fibroblast cells. The other nAu-containing grafts showed toxicological properties in the concentration range of 200-50 µg/mL and nAg-containing grafts in the concentration range of 200-100 µg/mL against the negative control. The micronucleus (MN) analyses showed that the lowest total MN and L (lobbed) amounts, while the lowest total N (notched) amount, was obtained from the only HAp graft. It was found that the nAg-doped bone grafts gave higher total MN, L, and N amounts compared to the nAu-doped bone grafts. Furthermore, while the mean nuclear abnormality (NA) values of all grafts gave close results, the highest values were again obtained from the nAg-doped bone grafts.

Boron-incorporated biocomposite coatings on 316L and NiTi alloys: Enhanced structural, antibacterial activity, and cell viability performances.

Boron doped (5 %, 10%, and 15 wt.%) Hydroxyapatite (B-HA) biocomposites were syntesized and coated on 316L SS and NiTi (Ni-45Ti) metallic substrates by using the electrophoretic deposition process (EPD). The morphological and structural characterization of the coatings was executed using scanning electron microscopy (SEM) and X-ray diffraction devices (XRD). Antibacterial tests were conducted using Escherichia coli (E. coli, JM103) and Staphylococcus aureus (S. aureus, ATCC29293) microorganisms. The mitochondrial activity assay (MTT)-[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] was used to examine cell viability and cytotoxicity in Saos-2 osteoblast cells. HA and boron peaks, as well as B-TCP and metallic components, were detected in XRD examinations. Porous morphologies were generated on the surface with boron doped B-HA coatings, as revealed by SEM views. Antibacterial activity studies revealed that both metallic coating groups, notably with boron doping, demonstrated antibacterial activity against gram-negative E. coli and gram-positive S. aureus. The antibacterial activity of the 316L group was shown to be better than that of the NiTi group in comparisonal testing. The syntesized boron-doped biocomposite coatings did not have any detrimental effects on living cells, according to cell viability studies. The cell viability rate was found to be greater in NiTi coatings than in 316 SS coatings, and the impact was amplified by the addition of boron.

Sonographic measurements of Inferior Vena Cava, Aorta, anda IVC/aorta ratio in healthy children.

Background: Assessment of intravascular volume status is important in pediatric patients admitted to the emergency departments and pediatric intensive care units. Inferior vena cava (IVC) diameter and collapsibility index are used to evaluate the intravascular volume status in adults. The normal range of IVC diameter is available for adults and the normal range considered for adults is between 1.7 to 2.1 cm, but such normative data is limited for children of all ages. Aims: Our aim in this study was to obtain the IVC and the aorta diameter reference values and the mean vena cava collapsibility index in healthy and normovolemic children. Subjects and Methods: Vena cava inferior and aorta images in B mode were obtained. IVC diameter in the inspiratory and the largest IVC diameter in the expiratory were recorded, and the vena cava collapsibility index was calculated. Results: Ultrasonographic measurements were performed in total on 1938 children. A significant positive correlation was found between IVC and aorta diameters with age. The collapsibility index was found as 37.2% (SD 11.8) in the overall study population. In addition, the reference values for the IVC and aorta diameters obtained from the measurements were also acquired. Conclusions: We believe that our IVC and aorta diameter measurements obtained from a large number of participants may be used as reference values in emergency departments and intensive care units.

Fabrication of porous-Ti6Al4V alloy by using hot pressing technique and Mg space holder for hard-tissue biomedical applications.

Porous-Ti6Al4V (P-Ti6Al4V) alloys were produced using the hot pressing and spacer methods for hard tissue biomedical applications and in particular, the effects of porosity on the mechanical and morphological properties of the structures were investigated. P-Ti6Al4V structures having the homogeneously distributed porosities at 41.08, 52.37 and 64.10% were fabricated by adding 40, 50 and 60% spherical magnesium (Mg) powder with 350 µm particle sizes in average as spacers and evaporating magnesium via the atmosphere-controlled sintering. The obtained porous structures were characterized by SEM, XRD and EDS. Furthermore, the strength and elastic modulus were evaluated by performing compression tests. Elastic modulus and densities were found to be 40-171 MPa, 2-5 GPa and 1.59-2.61, respectively and these values have been shown to decrease with an increase in porosity. The achieved density and mechanical property values, in particular, elastic modulus are close to human bone and within acceptable ranges for with biomedical application purposes. In addition, it was also found out from the analysis of produced P-Ti6Al4V that macropores were responsible for mechanical anisotropy contributed to formation of homogeneous and inter-connected open pores.

Comparison of two methods for the rapid radiochemical analysis of air dust samples in emergency situations.

The reliable determination of airborne radionuclides in air is a key aspect in decision-making for the protection against public exposure in the event of a nuclear or radiological emergency. Nowadays, this needs to be done in real time and at the international level. These needs require the development of fast response protocols and the harmonisation of results. This work presents two fast radiochemical methods for the simultaneous separation of alpha and beta emitters in aerosols and their performance in a series of samples.

Effects of varying entry points and trendelenburg positioning degrees in internal jugular vein area measurements of newborns.

BACKGROUND: Recent guidelines from the National Institute for Clinical Excellence recommend the use of ultrasonography in the central venous catheterization of children. In this study, we aimed to compare area measurements using ultrasonography and efficiency of varying Trendelenburg degrees on the area measurements, for two different entry points used as internal jugular vein (IJV) cannulation points in newborns. METHODS: Fifty-eight healthy newborns, weighing between 3000 and 3500 g, were recruited for this prospective study. Right IJV (RIJV) consecutive measurements were performed in three different Trendelenburg positions at 0°, 15°, and 30°, at two different entry points: The superior approach and an inferior approach. The landmark used in the superior approach was the top of the triangle formed by the two heads of the sternocleidomastoid muscle with the clavicle; while in the inferior approach, it was taken as the midpoint of the clavicle, as measured from the upper edge of the clavicle. RESULTS: The cross-sectional area (CSA) of the RIJV was significantly increased when using the inferior approach, compared to that in the superior approach, in all Trendelenburg degrees, including the neutral position. Both 15° and 30° Trendelenburg positioning resulted in a significant increase in CSA, both in superior and inferior approaches, when compared to neutral positioning. CONCLUSION: The use of 15° Trendelenburg positioning may have significant advantage for increasing the CSA when used with the inferior approach.

A review of the TAEA proficiency test on natural and anthropogenic radionuclides activities in black tea.

A proficiency test amongst 15 Turkish laboratories with participation of 5 non-Turkish laboratories was organized to determine the 137Cs, 40K and 90Sr massic activities in black tea powder samples. The bulk material, consisting of tea produced in 2014, was mixed with contaminated tea that was withdrawn from the market after the Chernobyl accident. Nineteen laboratories reported 41 results. The evaluation of the results was based on the accuracy and precision criteria adopted by the IAEA Proficiency Testing Group and resulted in 49% acceptable results, 19% acceptable with warning and 32% were found to be not acceptable.

Purification and characterization of polyphenol oxidase from corn tassel.

In this study, polyphenol oxidase (PPO) from corn tassel  was extracted and partially purified through  (NH4)2SO4 precipitation and gel filtration chromatography. Optimal temperatures for subsrates catechol and 4-methyl catechol were 40 °C and 30 °C, respectively. The optimal pH values were 8.0 for catechol and 6.0 for 4-methyl catechol. Catechol was the most suitible substrate (Km: 3.48 mM, Vmax: 1.0 Abs./ min.). The moleculer mass of PPO was determined as 158 kDa. In this work, sodium azide, ethylenediaminetetraacetic acid (EDTA) and sodium dodecyl sulfate (SDS) were found to inhibit the enzyme activity as 26.6 %,  22.2 % and 12.2 % ratio, respectively. Besides, the effects of carbohydrates such as sucrose, fructose, ribose and glucose on PPO activity were investigated. The enzyme was found to be activated 17 % by fructose and ribose, 16 % by glucose and 4 % by sucrose.

VACTERL association with a rare vertebral anomaly (butterfly vertebra) in a case of monochorionic twin.

The VATER/VACTERL association is typically defined by the presence of at least three of the following congenital malformations: vertebral anomalies, anal atresia, cardiac malformations, tracheo-esophageal fistula, renal anomalies, and limb abnormalities (13). We report a rare case of a monochorionic twin gestation in which one of the infants had VACTERL association. Antenatal ultrasound showed bilateral renal dysplasia and cardiac anomaly (ASD) in twin A. Twin A was noted to have the following anomalies: a single umbilical artery, limb anomaly (right hand preaxial polydactyly), vertebral anomalies (T9 and T11 butterfly vertebras, bilateral renal agenesis, bladder agenesis, anal and urethral atresia. A normal-sized stomach and normal amount of amniotic fluid were observed during the prenatal period with no other anomalies. Twin B (male) was healthy and no cardiac, renal, or congenital anomalies were demonstrated on ultrasound and physical examination. Infant A was also diagnosed as having VACTERL association because he had five of the core anomalies (V, A, C, R, L) of VACTERL association. Butterfly vertebra is an uncommon congenital spinal anomaly. To the best of our knowledge, our patient is the second case VACTERL association with butterfly vertebra in the literature.

Low Temperature Plasma for decontamination of E. coli in milk.

Raw milk is a natural, highly nutritious product and a quick and easy supplement for human dietary requirements. Elimination of bacteria in milk has been a problem for decades and new methods with regards to non-thermal applications which do not harm the chemical composition of milk, are currently under investigation. The objective of the study was to determine the potential use of a novel, Low Temperature Plasma (LTP) system for its capability of killing Escherichia coli in milk with different fat contents. The time dependent effect of atmospheric corona discharge generated with 9kV of AC power supply on E. coli ATCC 25922 dispersed in whole, semi skimmed and skimmed milk was examined. Plasma was applied at time intervals of 0, 3, 6, 9, 12, 15 and 20min. A significant 54% reduction in the population of E. coli cells after only 3min was observed regardless of the fat content of the milk. The initial pre-plasma bacterial count of 7.78 Log CFU/ml in whole milk was decreased to 3.63 Log CFU/ml after 20min of plasma application. LTP did not cause any significant change to the pH and color values of raw milk samples. No viable cells were detected after one week examination in whole milk samples and remained so over the 6week storage period. The findings of this study show that the novel LTP system tested was able to significantly reduce E. coli in milk by more than a 3 fold log reduction without significantly affecting pH or color properties.

Hepatitis C virus-specific T cell responses against conserved regions in recovered patients.

For the design of peptide-based vaccines against the hepatitis C virus it is essential to acquire more information on frequently recognized epitopes in patients with successful immune control of HCV in the context of different HLA types. A matrix approach using 393 15mer peptides from conserved HCV regions overlapping by 13 amino acids was applied in 52 HCV-recovered individuals. Candidate peptides were further tested in two independent laboratories. 38 peptides induced IFN-gamma responses in ELISPOT assays including 15 previously unknown epitopes. There was no particular immune dominance as only five peptides were recognized by more than three individuals. Seven out of 14 peptides tested in more detail could be confirmed to be immunogenic using ELISPOT and cytotoxicity assays. While only 33% of HCV-recovered individuals recognized recombinant HCV proteins, 81% of individuals tested positive in the matrix approach (p<0.001). The strength, frequency and breadth of HCV-specific T cell responses were similar in spontaneously recovered patients than in interferon-recovered patients. In conclusion (i) we identified novel HCV epitopes in conserved regions, (ii) confirmed the inter-individual diversity of HCV-specific T cell responses and (iii) found no significant differences in HCV-specific T cell responses between spontaneously recovered and IFN-recovered patients.

Impaired TRAIL-dependent cytotoxicity of CD1c-positive dendritic cells in chronic hepatitis C virus infection.

Dendritic cells (DCs) play a central role in antiviral immunity. Conflicting data on DC function have been reported for hepatitis C virus (HCV) infection. In addition to antigen presentation and cytokine secretion, a subset of human DCs displays direct cytotoxic activity. It has been suggested that measles virus and human immunodeficiency virus (HIV) may enhance cytotoxicity of DCs potentially leading to apoptosis of activated T cells and subsequent down-regulation of antiviral immune responses. We demonstrate that CD1c-positive myeloid DCs, but not BDCA-4-positive plasmacytoid DCs, are able to kill different target cells mainly via tumour necrosis factor-related apoptosis-inducing ligand. The ability of CD1c+ DCs to lyze target cells was found to be completely impaired in patients with chronic hepatitis C (10 chronic HCV patients vs 10 healthy controls; P < 0.001) but not in patients with primary biliary cirrhosis. Successful antiviral therapy of chronic hepatitis C rescued the cytotoxicity of DCs. Myeloid DCs of HCV patients and healthy controls had a similar phenotype and endocytotic activity, however, the frequency of mDCs in the peripheral blood was lower (P = 0.004) and the allostimulatory function was weaker (P < 0.001) in chronic hepatitis C. Thus, in contrast to HIV and measles virus studies on monocyte-derived DCs, freshly isolated myeloid DCs of patients with hepatitis C do not show an increased but a completely abolished cytotoxic activity. The impaired DC cytotoxicity could represent a novel mechanism for the increased prevalence of autoimmunity in HCV infection.

Advanced stage of cervical carcinoma undiagnosed during antenatal period in term pregnancy and concomitant metastasis on episiotomy scar during delivery: a case report and review of the literature.

The objective of this study is to review the implantation of malignant cells of cervical cancer in an episiotomy site. This is the second case of cervical cancer with concomitant episiotomy metastasis in the literature. The treatment consisted of radiochemotherapy. There was no confirmed recurrent disease after 1 year of follow-up in our reported case. In conclusion, pregnancy appears to be a chance for cervical cancer screening as a part of prenatal care. If cervical cancer is diagnosed in a woman after vaginal delivery, she must be examined carefully including the episiotomy site.

Induction of hepatitis C virus (HCV)-specific T cells by needle stick injury in the absence of HCV-viraemia.

BACKGROUND: The risk of hepatitis C virus (HCV) infection after occupational exposure is low with seroconversion rates between 0 and 5%. However, factors associated with natural resistance against HCV after needle stick injury are poorly defined. HCV-specific T-cell responses have been described in cross-sectional studies of exposed HCV-seronegative individuals. MATERIALS AND METHODS: In this study, we prospectively followed 10 healthcare professionals who experienced an injury with an HCV-contaminated needle. Blood samples were taken on the day or the day after the event and at different time points during follow-up for up to 32 months. HCV-specific T-cell responses were investigated directly ex vivo and in T-cell lines. RESULTS: None of the individuals became positive for HCV-RNA in serum tested with the highly sensitive transcription-mediated amplification (TMA)-assay or in peripheral blood mononuclear cells (PBMC). All of them remained anti-HCV negative throughout follow-up. At the time of injury, HCV-specific CD4+ T-cell responses were already detectable in two individuals and became detectable thereafter in three additional persons. Transient HCV-specific CD8+ T-cell responses developed in two HLA-A2 positive patients, which became negative until the most recent follow-up after 5 and 17 months, respectively. CONCLUSION: We demonstrate the development of HCV-specific T cells in HCV-exposed individuals after needle stick injury indicating subinfectious exposure to HCV. T-cell immunity against HCV may contribute to the low prevalence of HCV in medical healthcare professionals in Western countries.

Cytotoxic CD4 T cells in viral hepatitis.

CD4+ T cells are thought to contribute to antiviral immune responses by secretion of cytokines thereby providing help to CD8+ T and B cells. However, perforin-positive cytotoxic CD4+ T cells have been described in human immunodeficiency virus-positive patients suggesting a role not only of CD8+ but also of CD4+ T cells for killing virus-infected cells. We investigated 76 patients with viral hepatitis [15 hepatitis B virus (HBV), 22 HBV/hepatitis D virus and 17 hepatitis C virus (HCV)] for cytotoxic CD4+ T cells. The frequency of perforin-positive CD4+ T cells in viral hepatitis was highly variable ranging from < 1% to more than 25%. Perforin-positive CD4+ T cells displayed the phenotype of terminally differentiated effector cells (CD28-, CD27-). The highest frequencies of CD4+ cytotoxic T lymphocytes (CTLs) were found in patients with delta hepatitis (P = 0.04 vs HBV and HCV patients), and the presence of CD4+ CTLs was associated with elevated aspartate aminotransferase levels (P = 0.01) and decreased platelet counts (P = 0.03). Perforin-positive CD4+ T cells decreased in two individuals during spontaneous clearance of acute hepatitis C. Significant associations were found between the frequency of perforin-expressing CD4+ cells and age (P = 0.04), perforin-positive CD8+ cells (P < 0.001) and perforin-positive CD4-/CD8- lymphoid cells (P = 0.002). Differentiated CD27- effector CD4+ CTLs can be detected in patients with viral hepatitis. In particular in patients with more advanced liver disease, the accumulation of perforin-positive T cells with age could be one correlate for the more severe course of viral hepatitis in elderly individuals.

Molecular epidemiology of hepatitis B, C and D viruses in Turkish patients.

Different genotypes of the hepatitis viruses may influence the clinical outcome of the disease. The distribution of genotypes may vary according to geographical regions. The aim of this study was to evaluate hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) genotypes in Turkish patients with chronic hepatitis in a large cohort of patients. Genotyping was performed in 41, 59 and 365 patients with chronic hepatitis B, D and C, respectively, and 36 hemodialysis patients with chronic hepatitis C. Genotypes were determined by direct sequencing in hepatitis B and by polymerase chain reaction-restriction fragment length polymorphism in hepatitis C and D patients. In addition, HBV subtyping by multiplex PCR and subtype specific ELISA were performed in 83 and 71 HBsAg (+) blood donors, respectively. All hepatitis B (100%) and hepatitis D (100%) patients had genotype D and type I, respectively. HBsAg subtyping by two methods yielded that 99% of the patients were subtype ayw. S gene amino acid sequence in the 41 patients included for HBV genotyping revealed the ayw2 subtype. Genotype distribution of 365 patients with chronic C hepatitis were as follows: 306 (84%) patients genotype 1b, 43 (11%) patients genotype 1a, 10 (3%) patients genotype 2, 3 (1%) patients genotype 3, 3 (1%) patients genotype 4. Among 36 patients receiving hemodialysis, 28 (78%) patients had genotype 1b and 8 (22%) patients had genotype 1a. The study indicates that Turkish patients with chronic viral hepatitis show very little genotypic heterogeneity. Subtype ayw and the genotype D of HBV DNA, and the type I of HDV RNA represent almost 100% of related infections. The genotype 1b of HCV RNA was found to be significantly dominant in Turkish patients.

YSDD: a novel mutation in HBV DNA polymerase confers clinical resistance to lamivudine.

The emergence of drug-resistant virus in hepatitis B virus (HBV) patients treated with lamivudine is well documented. In this study, we determined the mutations occurring in the tyrosine-methionine-aspartate-aspartate (YMDD) amino acid motif of the HBV DNA polymerase gene, as well as upstream and downstream of this region, in patients with breakthrough virus during lamivudine therapy. Thirty-one Turkish patients (20 patients HBeAg positive, 11 patients HBeAg negative and anti-HBe positive) with chronic HBV infection who completed at least 104 weeks of lamivudine treatment were investigated. All patients received lamivudine, (150 mg/day), for 104 weeks, with or without 4 months of interferon (IFN) combination. HBV-specific sequences were amplified by polymerase chain reaction (PCR) from sera of patients with breakthrough virus, and the PCR products were directly analysed by sequencing. Breakthrough virus was detected in seven of the 31 patients (22.6%) between 9 and 18 months of therapy. Of the seven patients, six were HBeAg positive at baseline, and four had a double mutation consisting of rtM204V and rtL180M, while two had an rtM204I change. In one patient, two base substitutions at rt204 (ATG --> AGT; T to G and G to T) lead to a methionine to serine change (YMDD --> YSDD). This novel DNA pol mutation was detected at month 18 of lamivudine treatment. In addition, this new variant had the rtL180M mutation and a 12 base pair deletion in the pre-S1 region between nucleotides 43-54. The YSDD mutation was still present 6 months after lamivudine discontinuation. In vitro transfection studies also confirmed that the YSDD strain is resistant to lamivudine. In conclusion, the results indicate that, in addition to a Met --> Val and Met --> Ile change in YMDD, a Met --> Ser change at rt204 (YMDD --> YSDD) associated with the rtL180M change can also emerge during lamivudine treatment, which confers lamivudine resistance in vivo and in vitro, leading to virological breakthrough and ALT increases.

A nitrate-selective electrode based on tris(2,2',2"-salicylideneimino)triethylamine.

A new nitrate-selective liquid-membrane electrode based on the tris(2,2',2"-salicylideneimino)triethylamine-iron(III) complex has been developed. This electrode exhibits a linear Nernstian response over the range 10(-1)-10(-4) M of nitrate, with a slope of 54.3 +/- 0.9 mV per p[NO3]. The effects of the pH and the liquid-membrane composition were also investigated. The lifetime of the electrode is at least one month. The selectivity coefficients for ten monovalent ions were calculated. The preparation procedure of the electrode is very easy and inexpensive. Moreover, the proposed electrode was applied for the determination of nitrate in fertilizers.

Circulating IL-2 and IL-10 in chronic active hepatitis C with respect to the response to IFN treatment.

BACKGROUND: The importance of circulating immunoregulatory cytokines in response to IFN treatment and the change of in vivo production of these cytokines during interferon (IFN) treatment are not well known. We aimed to determine whether pretreatment serum levels of IL-2 and IL-10 are predictive of the response to IFN treatment and to investigate if treatment response or nonresponse has any effect on the circulating levels of these cytokines. PATIENTS AND METHODS: 37 patients (18 responders and 19 non-responders) with chronic hepatitis C virus (HCV) infection who received IFN-alpha2b for 6 months were studied. Responders were defined by complete alanine aminotransferase (ALT) normalization and loss of HCV RNA as detected by bDNA assay while patients who had elevated ALT levels and positive HCV RNA after 6 months were considered as nonresponders. RESULTS: Genotype distribution, ALT and HCV RNA levels were similar in responders and nonresponders. A significant number of patients with chronic hepatitis C (20/37 = 54%) had elevated IL-2 levels while IL-10 levels were not different from controls. No difference in baseline cytokine levels was observed between responders and non-responders. In the posttreatment serum samples some patients lost their detectable IL-2 or IL-10; some patients developed detectable cytokine levels after treatment irrespective of the treatment response. CONCLUSION: These results suggest that active liver injury in chronic hepatitis C is associated with increased circulating Th1 cytokine IL-2 but not with Th2 cytokine IL-10 and that circulating levels of these cytokines do not predict the response to IFN treatment. There is no constant and regular change in circulating levels of these cytokines under IFN treatment with respect to treatment response.