Shaping scaffold structures in rapid manufacturing implants: A modeling approach toward mechano-biologically optimized configurations for large bone defect

Large segmental bone defects remain a clinical challenge. Titanium lattice-structured implants in combination with laser sintering technology promises to be an alternative to bone grafting in the treatment of critical sized bone defects. Laser sintering allows the rapid manufacturing of patient specific 3D-structured scaffolds with highly interconnected macroporous networks and tunable mechanical properties. Unknown remains to what degree the mechanical properties of these implants could be tuned, without leading to mechanical failure but still providing adequate mechanical stimuli for tissue ingrowth. The aim of this study was to evaluate various implant designs for their mechanical potential towards (a) optimized safety against stress failure and (b) optimal intrastructural straining for bone ingrowth. Finite element analyses of several lattice-structured configurations were performed. Results illustrated a strong influence of the configuration on the load carrying capacity of the constructs. The likelihood of mechanical failure was predicted to be highly dependent on structure configuration with little influence of implant porosity. Increasing porosity did not result in an increase in the implant intrastructural straining in all configurations; however, the lattice configuration was the determinant factor for implant load transfer capacity. This study provides a framework for the design of effective implants with open pore structures to ensure mechanical stability as well as promote mechanical stimulation and encourage in vivo osseointegration. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.     

Effect of Curcuma longa L. extract on the AP1 expression in rat cochlear fibroblasts under noise conditions

Noise-induced cellular stress can cause damage to fibroblasts within the cochlear supporting tissues and lateral wall. In the present study, we aimed to evaluate the role of curcumin as the safe and effective therapeutic agent in the prevention and treatment of this condition according to the expression of activator protein-1 (AP1). A total of 24 Rattus norvegicus were randomly divided into four groups (n = 6). Group 1: control; group 2: noise (+); group 3: noise (+), 50 mg/day curcumin (+); group 4: noise (+), 100 mg/day curcumin (+). All groups (except for group 1) were subjected to a sound pressure level (SPL) of 100 dB for 2 h/day during 2 weeks. Curcumin used in this study was derived from Curcuma longa L. (Turmeric), and it was orally administered for 2 weeks. All samples were immunohistochemistrically examined for the expression of AP1 in cochlear fibroblasts. The results showed that there were significant differences for the AP1 expression (P<0.05) among all groups, except for between groups 1 and 3, or between groups 1 and 4. Our data proved that curcumin was potentially effective in the prevention and treatment of damage of fibroblasts within the cochlear supporting tissues and lateral wall due to the decreased AP1 expression following noise exposure.     

A survey of incidental ocular trauma by pencil and pen

AIM: To determine characteristic features of ocular trauma resulted from self-trauma by writing instruments among pediatric population. METHODS: Thirty-six children who suffered from self-inflicted ocular trauma with a writing instrument were included in this prospective cross-sectional study. RESULTS: The mean age was 5.6±2.7y with male: female ratio of 1.77. The right eye was involved two times more than the left eye. The superomedial (55.5%) and inferomedial (30.6%) quadrants were the most common sites of injury. The leading culprit was colored pencils (44.4%). During surgical exploration, no foreign body (FB) was found in 25 (69.4%) patients while an FB was found in 11 (30.5%) patients. Brain injury was present in two patients (5.6%) and only in superomedial quadrant injuries. Zone 1 was the most common site for ocular trauma associated with penetrating injury. The mean ocular trauma score (OTS) in penetrating injuries was 3.8±1.2. The best corrected visual acuity (BCVA) was 0.3±0.6 upon admittance and 0.08±0.21 after one year. The final BCVA was significantly correlated with the entrance site, better final BCVA was found in nasal entrance site (P<0.05). CONCLUSION: The ophthalmologists should keep a high index of suspicion to rule out penetrating eye injuries related to writing instruments in a young uncooperative child. Brain injury is a life-threatening event that should be ruled out by appropriate imaging. Medial canthal area as the most common site needs an especial attention in writing instrument injuries.     

Lack of significance of the BRCA2 promoter methylation status in different genotypes of the MTHFR a1298c polymorphism in ovarian cancer cases in Iran

Objective: Promoter methylation, which can be regulated by MTHFR activity, is associated with silencingof genes. In this study we evaluated the methylation status (type) of the BRCA2 promoter in ovarian cancerpatients carrying different genotypes of the MTHFR gene (A or C polymorphisms at position 1298). Methods:The methylation type of the BRCA2 promoter was evaluated using bisulfate-modified DNA in methylationspecificPCR and the MTHFRa1278c polymorphism was assessed by PCR-RFLP. Results: Analysis of theBRCA2 promoter methylation type of cases showed that 7 out of 60 cases (11.7%) were methylated while theremaining 53 (88.3%) were unmethylated. In methylated cases, one out of the 7 cases had a CC genotype andthe remaining 6 methylated cases had an AC genotype. The AA genotype was absent. In unmethylated cases,34, 18, and one out of these had AC, AA and CC genotype, respectively. Conclusion: There was no significantrelationship between the methylation types of the BRCA2 promoter in different genotypes of MTHFRa1298cpolymorphism in ovarian cancer; p=0.255. There was no significant relation between the methylation types ofthe BRCA2 promoter in different genotypes of the MTHFRa1298c polymorphism in ovarian cancer.     

Cadasil syndrome: A case report with a literature review

“CADASIL” is a genetic microangiopathy with autosomal dominant inheritance. Its epidemiology and physiopathogenesis are poorly specified, but it is proven that this disease is due to a mutation of the NOTCH3 gene resulting in a loss of elasticity of the media of the affected vessels. The clinical expression is variable, dominated by migraine attacks with aura, ischemic vascular accidents and psychiatric disorders, in particular depression. MRI is essential for diagnosis even in the pre-symptomatic phase. It shows signal abnormalities in the basal ganglia and white matter, characteristic especially when located in the anterior part of the temporal lobes. The management of CADASIL is multidisciplinary, psychological for the most part without specificity of a particular treatment.     

Sarcopenia Prevalence and Risk Factors among Residents in Aged Care

The aim of this study was to investigate the prevalence of sarcopenia and associated risk factors among older adults living in three residential aged care (RAC) facilities within Auckland, New Zealand. A total of 91 older adults (63% women, mean age ± SD; 86.0 ± 8.3 years) were recruited. Using the European Working Group on Sarcopenia in Older People criteria, sarcopenia was diagnosed from the assessment of: appendicular skeletal muscle mass/height², using an InBody S10 body composition analyser and a SECA portable stadiometer or ulna length to estimate standing height; grip strength using a JAMAR handheld dynamometer; and physical performance with a 2.4-m gait speed test. Malnutrition risk was assessed using the Mini Nutrition Assessment–Short Form (MNA-SF). Most (83%) of residents were malnourished or at risk of malnutrition, and 41% were sarcopenic. Multivariate regression analysis showed lower body mass index (Odds Ratio (OR) = 1.4, 95% CI: 1.1, 1.7, p = 0.003) and lower MNA-SF score (OR = 1.6, 95% CI: 1.0, 2.4, p = 0.047) were predictive of sarcopenia after controlling for age, level of care, depression, and number of medications. Findings highlight the need for regular malnutrition screening in RAC to prevent the development of sarcopenia, where low weight or unintentional weight loss should prompt sarcopenia screening and assessment.     

Spatio-temporal Distribution of Suicide Risk in Iran: A Bayesian Hierarchical Analysis of Repeated Cross-sectional Data

ObjectivesWe aimed to estimate the space-time distribution of the risk of suicide mortality in Iran from 2006 to 2016.MethodsIn this repeated cross-sectional study, the age-standardized risk of suicide mortality from 2006 to 2016 was determined. To estimate the cumulative and temporal risk, the Besag, York, and Mollié and Bernardinelli models were used.ResultsThe relative risk of suicide mortality was greater than 1 in 43.0% of Iran’s provinces (posterior probability >0.8; range, 0.46 to 3.93). The spatio-temporal model indicated a high risk of suicide in 36.7% of Iran’s provinces. In addition, significant upward temporal trends in suicide risk were observed in the provinces of Tehran, Fars, Kermanshah, and Gilan. A significantly decreasing pattern of risk was observed for men (β, −0.013; 95% credible interval [CrI], −0.010 to −0.007), and a stable pattern of risk was observed for women (β, −0.001; 95% CrI, −0.010 to 0.007). A decreasing pattern of suicide risk was observed for those aged 15–29 years (β, −0.006; 95% CrI, −0.010 to −0.0001) and 30–49 years (β, −0.001; 95% CrI, −0.018 to −0.002). The risk was stable for those aged >50 years.ConclusionsThe highest risk of suicide mortality was observed in Iran’s northwestern provinces and among Kurdish women. Although a low risk of suicide mortality was observed in the provinces of Tehran, Fars, and Gilan, the risk in these provinces is increasing rapidly compared to other regions.