Taking Hydroxyapatite-Coated Titanium Implants Two Steps Forward: Surface Modification Using Graphene Mesolayers and a Hydroxyapatite-Reinforced Polymeric Scaffold.

Coating with hydroxyapatite (HAP) presents a mainstream strategy for rendering bioinert titanium implants bioactive. However, the low porosity of pure HAP coatings does not allow for the infiltration of the surface of the metallic implant with the host cells. Polymeric scaffolds do enable this osseointegration effect, but their bonding onto titanium presents a challenge because of the disparity in hydrophilicity. Here, we demonstrate the inability of a composite scaffold composed of carbonated HAP (CHAP) nanoparticles interspersed within electrospun ε-polycaprolactone (PCL) nanofibers to bind onto titanium. To solve this challenge, an intermediate layer of graphene nanosheets was deposited in a pulsed laser deposition process, which facilitated the bonding of the scaffold. The duration of the deposition of graphene (0, 5, 10, 15, and 20 min) and the thickness of its mesolayer affected numerous physical and chemical properties of the material, including the surface atomic proportion of carbon bonds, the orientation and interlinking of the polymeric nanofibers, and the surface roughness, which increased in direct proportion with the thickness of the graphene mesolayer. Because the polymeric scaffold did not adhere onto the surface of pure titanium, no cells were detected growing on it in vitro. In contrast, human fibroblasts adhered, spread, and proliferated well on all the substrates sputtered with both graphene and the composite scaffold. The orientations of cytoskeletal filopodia and lamellipodia were largely determined by the topographic orientation of the nanofibers and the geometry of the surface pores, attesting to the important effects that the presence of a scaffold has on the cellular behavior. The protection of titanium from corrosion in the simulated body fluid (SBF) was enhanced by coating with graphene and the composite scaffold, with the most superior resistance to the attack of the corrosive ions being exhibited by the substrate subjected to the shortest duration of the graphene deposition because of the highest atomic ratio of C-C to C-O bonds detected in it. Overall, some properties of titanium, such as roughness and wettability, were improved monotonously with an increase in the thickness of the graphene mesolayer, while others, such as cell viability and resistance to corrosion, required optimization, given that they were diminished at higher graphene mesolayer thicknesses. Nevertheless, every physical and chemical property of titanium analyzed was significantly improved by coating with graphene and the composite scaffold. This type of multilayer design evidently holds a great promise in the design of biomaterials for implants in orthopedics and tissue engineering.

Physical, electrochemical and biological evaluations of spin-coated ε-polycaprolactone thin films containing alumina/graphene/carbonated hydroxyapatite/titania for tissue engineering applications.

Composite structures are at the frontier of materials science and engineering and polymeric/ceramic composites present one of their most prospective subsets. Prior studies have shown both improvements and deteriorations of properties of polymers upon the addition of ceramic phases to them, but not many studies have dealt with the direct comparison of chemically distinct inorganic additives. The goal of this study was to compare the properties of ε-polycaprolactone (PCL) thin films supplemented with alumina, graphene, carbonated hydroxyapatite or titania particles, individually, in identical amounts (12 wt%). The composite films were analyzed for their phase composition, grain size, morphology, surface roughness, porosity, cell response, mechanical properties and electrochemical performance. Each additive imparted one or more physical or biological properties onto PCL better than others. Thus, alumina increased the microhardness of the films better than any other additive, with the resulting values exceeding 10 MPa. It also led to the formation of a composite with the least porosity and the greatest stability to degradation in simulated body fluid based on open circuit potential (OCP) measurements and electrochemical impedance spectroscopy (EIS). Titania made the surface of PCL roughest, which in combination with its high porosity explained why it was the most conducive to the growth of human fibroblasts, alongside being most prone to degradation in wet, corrosive environments and having the highest Poisson's ratio. Graphene, in contrast, made the surface of PCL smoothest and the bulk structure most porous, but also most conductive, with the OCP of -37 mV. The OCP of PCL supplemented with carbonated hydroxyapatite had the highest OCP of -134 mV and also the highest mechanical moduli, including the longitudinal (781 MPa), the shear (106 MPa), the bulk (639 MPa), and the elastic (300 MPa). The only benefit of the deposition of multilayered PCL films supplemented with all four inorganic additives was to enable a relatively high resistance to degradation. This study demonstrates that the properties of thin PCL films could be effectively optimized through the simple choice of appropriate inorganic additives dispersed in them. There is no single additive that proves ideal for improving all the properties of interest in PCL thin films, but their choice should be adjusted to the actual application. One such method of compositional optimization could prove crucial in the effort to develop biocomposites for superior performance in tissue engineering applications.

Gold as a dopant in selenium-containing carbonated hydroxyapatite fillers of nanofibrous ε-polycaprolactone scaffolds for tissue engineering.

The necessity for finding a compromise between mechanical and biological properties of biomaterials spurs the investigation of the new methods to control and optimize scaffold processing for tissue engineering applications. A scaffold composed of ε-polycaprolactone fibers reinforced with carbonated hydroxyapatite (CHAP) dually doped with selenite oxyanions (Se) and cationic gold (Au) was synthesized using the electrospinning technique and studied at different contents of Au. Despite the fact that the amount of the Au dopant was relatively low, variations to it induced significant microstructural changes, affecting the cell response and mechanical properties in return. Au nanoparticles segregated as a separate, ternary phase at the highest Au content, corresponding to x = 0.8 in the AuxCa10-1.5x(PO4)5.8(SeO2)0.2-x(CO3)x(OH)2 stoichiometric formula of Au/Se-CHAP. Their appearance coincided with a rapid degeneration in the density and adhesion of osteoblastic cells grown on the scaffolds. In spite of this adverse effect, the cell spreading and proliferation improved with increasing the amount of the Au dopant in the Au/Se-CHAP particles of the scaffold in the x = 0.0-0.6 range, suggesting that the biological effects of Au in the ionic and in the nanoparticulate form on the implant integration process may be diametrically opposite. The addition of Au had a dramatic effect on some mechanical properties, such as toughness and strain at break, which were both reduced twice upon the introduction of Au into Se-CHAP at the lowest amount (x = 0.2) compared to the Au-free composite. The significant variation of physical and biological properties of these composite scaffolds with trace changes in the content of the Au dopant inside the ceramic filler particles is promising, as it provides a new, relatively subtle avenue for tailoring the properties of tissue engineering scaffolds for their intended biomedical applications.

Monosodium glutamate versus diet induced obesity in pregnant rats and their offspring.

BACKGROUND: We aim at determining the role of monosodium glutamate (MSG) compared with high caloric chow(HCC) in development of obesity in pregnant rats and their offspring. METHODS: Ninety pregnant rats were divided into 3 groups, control, MSG and HCC fed. We determined energy intake, body weight (BW), abdominal fat, fat to body weight ratio, serum glucose, insulin, leptin, lipid profile, ob and leptin receptor-b gene expressions in pregnant rats and ob and leptin receptor-b gene expressions, serum insulin,glucose, leptin, triacylglycerides (TAG), total lipids (TL) and BW in offspring. RESULTS: Although daily energy intake and BW of MSG treated rats were lower than those of HCC fed rats, their abdominal fat and fat body weight ratio were higher. MSG or HCC increased Ob gene expression, leptin, insulin,LDL, cholesterol, total lipids (TL), glucose and decreased leptin receptor-b gene expression. In offspring of MSG treated rats, BW, serum glucose, insulin, leptin, TAG, TL and Ob gene expression increased and leptin receptor-b gene expression decreased whereas in offspring of HCC fed rats, serum insulin, leptin, Ob and leptin receptor-b gene expression increased but serum glucose, TAG, TL or BW did not change. CONCLUSION: We conclude that in pregnant rats, MSG, in spite of mild hypophagia, caused severe increase in fat body weight ratio, via leptin resistance, whereas, HCC increased BW and fat body weight ratio, due to hyperphagia with consequent leptin resistance. Moreover, maternal obesity in pregnancy, caused by MSG, has greater impact on offspring metabolism and BW than that induced by HCC.

Dynamics of gas-phase trichloramine (NCl3) in chlorinated, indoor swimming pool facilities.

UNLABELLED: Trichloramine (NCl(3)) is recognized as an irritant of the human respiratory system and other tissues. Processes that lead to volatilization from the liquid phase allow for human exposure to gas-phase NCl(3) in swimming pool settings. The dynamics of these processes are not well defined. A N,N-diethyl-p-phenylenediamine/potassium iodide (DPD/KI)-based wet-chemistry method for measuring gas-phase NCl(3) concentration was verified and applied in chlorinated, indoor swimming pool facilities. Other gas-phase oxidants in the air of indoor pools provided interference of 15% or less. The DPD/KI method was applied for the measurement of gas-phase NCl(3) in four chlorinated, indoor swimming pool facilities. All results showed a correlation between bather loading and gas-phase NCl(3) concentration. The nature of swimmer activities also influenced air quality, presumably because of the effects of these activities on mixing near the gas-liquid interface. PRACTICAL IMPLICATIONS: The activities of swimmers promote transfer of volatile compounds from water to the surrounding air. For chlorinated, indoor pool facilities, this can lead to exposure to gas-phase chemicals that can cause irritation of the respiratory system and other tissues. The focus of this study was on NCl(3), a common disinfection by-product (DBP) in chlorinated pools. However, the conditions that promote NCl(3) transfer are likely to promote transfer of other volatile chemicals from water to air. As such, it is possible that other DBPs formed in pools may also contribute to diminished air quality.

Troubled minds in the Gulf: mental health research in the United Arab Emirates (1989-2008).

This article aims to describe the characteristics of the United Arab Emirates (UAE) mental health research published from 1989 to 2008 in PubMed indexed journals to identify gaps and to suggest recommendations. Our sensitive PubMed search for general and mental health publications in Gulf Cooperation Council (GCC) countries and the UAE revealed a total of 192 mental health studies published in GCC countries over the past 20 years, which constituted less than 1% of the GCC total biomedical research. Most of the studies were from the UAE University and were either epidemiologic (48.98%) or psychometric (24.49%) with no studies addressing mental health systems research. Underrepresented were studies on health promotion and interdisciplinary, cross-cultural, ethnic, and gender research. There is a need for more international collaboration and for policies that link research conducted to services provided with longitudinal studies to test the long-term impact of early preventive interventions.

Egyptian ever-married women's attitude toward discontinuation of female genital cutting.

INTRODUCTION: This study aimed to examine Egyptian ever-married women's beliefs and attitude toward the discontinuation of female genital cutting (FGC). We also examined the significant sources of information which the women with positive attitude were exposed to the year prior to the survey. METHODS: In a national representative community-based sample of 15,573 ever-married Egyptian women, the intention to continue the practice of FGC and other sociodemographical variables were collected from the 2000 Egypt Demographic and Health Survey data. A secondary in-depth analysis was conducted on the data in order to investigate the women's attitude and its associated factors. RESULTS: Only 12.4 percent of the sample intended to discontinue the practice. The logistic regression models showed that women with a positive attitude to discontinue the practice believed that FGC was not an important part of religious traditions, that husbands did not prefer a cut wife, and that FGC reduced sexual desire. The most significant sources of information related to a positive attitude to discontinue the practice were community discussions, the mosques or churches and the newspapers. CONCLUSION: The aforementioned sources of information are related to the social and religious aspects of women in the Egyptian community. In order to change women's attitude toward the discontinuation of this unhealthy practice, communication rather than passive learning is needed.

Role of Helicobacter pylori in refractory iron deficiency anaemia.

The role of Helicobacter pylori infection in the development of iron deficiency anaemia has been the focus of attention over the past decade. However, confirmation of a relationship has not confirmed the pathophysiological mechanisms involved in the phenomenon. The aim of the present work is to study the levels of fasting gastric acidity (free and total) as well as the level of tumour necrosis factor-alpha (TNF alpha) in male refractory iron deficiency anaemia patients seropositive for H. pylori infection versus those who are seronegative. Thirty adult patients with iron deficiency anaemia and gastroduodenitis were subdivided into two groups of matched age and haemoglobin value. Group 1 was H. pylori-seropositive for infection and these patients did not receive prior treatment for eradication of H. pylori infection. Group 2 comprised patients seronegative for H. pylori infection (control group). Patients with active bleeding or previous medical problems were excluded from the study. All patients and controls were subjected to the following at presentation: history taking and thorough clinical examination, complete blood picture, reticulocytes (%), assessment of serum iron, total iron binding capacity, serum ferritin, IgG anti-Helicobacter antibody and TNF alpha, stool for occult blood and measurement of gastric acidity (total and free). Upper endoscopy was performed and multiple biopsies were taken and tested for expression of cytotoxin-associated gene A (cagA) by the polymerase chain reaction (PCR). Results showed significantly higher values of free and total gastric acidity as well as TNF alpha levels in Group 1 compared to controls (Group 2). Among those in Group 1, higher TNF alpha levels were seen in seven H. pylori cagA-positive patients than in eight cagA-negative patients. Haemoglobin values were inversely correlated with TNF alpha levels. Thus, elevated serum TNF alpha in the H. pylori-seropositive group may be one of the underlying pathophysiological mechanism for iron deficiency anaemia observed in these patients.

Lactational amenorrhoea method for family planning and women empowerment in Egypt.

INTRODUCTION: This study aims to assess the potential for the lactational amenorrhoea method (LAM) and passive LAM among women with children below six months of age, and to examine its association with women empowerment in household decisions. METHODS: Data from the Egypt Demographic Health Survey 2000 was downloaded from the Demographic and Health Surveys website. A sub-sample of women fulfilling all four criteria were selected: (1) women whose last birth of children was less than three years ago; (2) currently married; (3) not sterilised; and (4) currently breastfeeding their children. Accordingly, only 3,447 women entered into the statistical analysis, of whom 1,141 had children below six months of age. RESULTS: Passive LAM users constituted 82 percent of the women who met LAM criteria, 57.1 percent of exclusive breastfeeding mothers, and 32.9 percent of all nursing mothers of children below six months of age. 11.8 percent of women who met the LAM criteria were under double coverage of family planning methods. In the logistic regression model where all variables were adjusted, women empowerment in household decisions, significantly and independently, inversely predicted passive LAM along with increase in child age (Odds-ratio [OR] of 0.86 and 0.43, respectively). Women with higher birth order children were more likely to use passive LAM (OR 1.11). CONCLUSION: Women of low empowerment index in household decisions were more likely to use passive LAM. Passive LAM users could be subjected to discontinuation or double coverage of contraceptives.

Gender differences in mental health.

Effective strategies for mental disorders prevention and its risk factors' reduction cannot be gender neutral, while the risks themselves are gender specific. This paper aims to discuss why gender matters in mental health, to explain the relationship of gender and health-seeking behaviour as a powerful determinant of gender differences, to examine the gender differences in common mental health disorders, namely, depressive and anxiety disorders, eating disorders, schizophrenia, and domestic violence, and finally, to raise some recommendations stemming from this review.

Health locus of control and depressive symptoms among adolescents in Alexandria, Egypt.

The aim of this work was to investigate the association of health locus of control with depression among adolescents in Alexandria, Egypt. The tools used were a self-report questionnaire covering demographic data and some factors associated with depression, the Multidimensional Health Locus of Control scale and the Child Depression Inventory. Adolescents with low internal health locus of control and high chance external health locus of control were more likely to have depressive symptoms than others in bivariate and multivariate analysis. The study findings demonstrated an association between health locus of control and adolescent depression.

Health locus of control and depressive symptoms among adolescents in Alexandria, Egypt

The aim of this work was to investigate the association of health locus of control with depression among adolescents in Alexandria, Egypt. The tools used were a self-report questionnaire covering demographic data and some factors associated with depression, the Multidimensional Health Locus of Control scale and the Child Depression Inventory. Adolescents with low internal health locus of control and high chance external health locus of control were more likely to have depressive symptoms than others in bivariate and multivariate analysis. The study findings demonstrated an association between health locus of control and adolescent depression

Positive health practices and depressive symptoms among high school adolescents in Oman.

INTRODUCTION: The study aimed to investigate the association of health practices and depressive symptoms among high school adolescents in a national representative sample of 5,409 students in Oman. METHODS: Depressive symptoms were screened in 2004 through the application of the self-report 27-item Child Depression Inventory. Health practices scale comprised a simple sum of five healthy practices, namely: sleeping seven to eight hours at night, having breakfast daily, not eating between meals, not smoking the month prior to the study, and doing physical activities more than once per week apart from attending physical education classes in school. RESULTS: Sequential logistic regression models were run to test for the change in the odds-ratio (OR) of having depressive illness with a one point increase in the healthy practices scale, after adjustment for other risk factors of depression. Health practices remained having a significant protective effect on depression (OR is 0.72, 95 percent confidence interval is 0.64-0.80) even after adjustment to other significant covariates in the last model, such as history of chronic medical or mental illness diagnosed by a doctor, high scoring in chance health locus of control (HLC), low scoring in internal HLC, poor relationships with social contacts, and physical abuse during childhood or adolescence. CONCLUSION: Findings support the protective effects of positive health practices on adolescents' depression.

Knowledge, attitudes and practices of secondary-school pupils in Oman: I. health-compromising behaviours.

We investigated the practice of some of health-compromising behaviours among Omani adolescents and their correlates in a nationally representative secondary school-based sample of 1670 boys and 1675 girls. The mean age of the sample was 17.13 (SD 1.35) years. Through a self-administrated questionnaire the adolescents were asked about 6 risky behaviours: current smoking, ever use of alcohol, succumbing to peer pressure to take illicit drugs, driving without a licence, speeding while driving and being involved in a physical fight in the month prior to the survey. Demographic and psychosocial variables related to their risk behaviours were also assessed. The results indicated that 4.6 % were current smokers, 4.3% had drunk alcohol and 4.6% had taken drugs. About 20% had been involved in a physical fight in the month prior to the survey, 33.4% drove without a licence and 33.9% liked to speed. Male sex and low self-esteem were the strongest predictors of risky behaviour.

Knowledge, attitudes and practices of secondary-school pupils in Oman: II. reproductive health.

We examined the knowledge, attitudes and practices of Omani adolescents with regard to reproductive health in a nationally representative secondary school-based sample of 1670 boys and 1675 girls. Through a self-administrated questionnaire the adolescents were asked about puberty, marriage, birth spacing and AIDS and sexually transmitted infections. Only half of the sample knew the changes at puberty of their own sex, while even fewer knew the changes in the opposite sex. Girls were inclined significantly towards later age of marriage than boys. The mean number of children desired by the sample was 4.9. About two-thirds of the adolescents had a positive attitude toward modern contraceptive methods and intended to use them in the future. Knowledge of fertility period was poor as was knowledge of AIDS and sexually transmitted infections. There was a high rate of approval (80%) of female genital cutting by both sexes.

Depression in adolescents: gender differences in Oman and Egypt.

To investigate the differences between adolescent boys and girls, the rates of depression and associated factors were determined for secondary school adolescents in 2 different samples, 552 in South Sharqiya, Oman, and 1577 in Alexandria, Egypt. Multivariate logistic regression models were used to investigate the correlates of depression. In Alexandria, the rate of having depressive symptoms in girls was almost double that in boys. In Oman, however, there was no significant difference. History of abuse during adolescence predicted depression in almost all the models. Poor relationship with parents affected girls more than boys in Alexandria and in the merged sample. Gender differences in rates or correlates of depression exist but may differ for different countries.