Synthesis methods for nanosized hydroxyapatite with diverse structures

Hydroxyapatite (HAp) is the major mineral constituent of vertebrate bones and teeth. It has been well documented that HAp nanoparticles can significantly increase the biocompatibility and bioactivity of man-made biomaterials. Over the past decade, HAp nanoparticles have therefore increasingly been in demand, and extensive efforts have been devoted to develop many synthetic routes, involving both scientifically and economically new features. Several investigations have also been made to determine how critical properties of HAp can be effectively controlled by varying the processing parameters. With such a wide variety of methods for the preparation of HAp nanoparticles, choosing a specific procedure to synthesize a well-defined powder can be laborious; accordingly, in the present review, we have summarized all the available information on the preparation methodologies of HAp, and highlighted the inherent advantages and disadvantages involved in each method. This article is focused on nanosized HAp, although recent articles on microsized particles, especially those assembled from nanoparticles and/or nanocrystals, have also been reviewed for comparison. We have also provided several scientific figures and discussed a number of critical issues and challenges which require further research and development.     

Management of Spasticity in Children with Cerebral Palsy

Cerebral palsy is the most common cause of spasticity and physical disability in children and spasticity is one of the commonest problems in those with neurological disease. The management of spasticity in children with cerebral palsy requires a multidisciplinary effort and should be started as early as possible. There are a number of treatments available for the management of spasticity. This article reviews the variety of options available for the clinical management of spasticity.Key Words: Cerebral Palsy, Intrathecal Baclofen, Occupational Therapy, Physical Therapy, Rhizotomy, Spasticity     

Body Fat Distribution and Its Association with Cardiovascular Risk Factors in Adolescent Iranian Girls

Objective

The relationships between body fat distribution, lipid profile and blood pressure, have not been studied extensively in young population. This study was designed to evaluate the association between measures of adiposity and established cardiovascular risk factors in adolescent girls.

Methods

A total of 477 adolescent girls aged 15 to 18 years were recruited from Mashhad high schools. Socio-demographic characteristics were assessed using a self-administered questionnaire. Anthropometric assessments, blood pressure measurement and biochemical assessment were performed. Total and regional fat mass were determined by bio-impedance analysis. Cardiovascular disease risk factors were assessed in relation to body fat measures with adjustment for confounder factors including age and family socioeconomic status.

Findings

The prevalence of overweight and obesity was 14.6% and 3.4% respectively; 16% of study population had greater fat mass compared to its ideal distribution. The majority of cardiovascular risk factors, especially systolic and diastolic blood pressure, triglyceride concentration, CRP and fasting blood sugar were significantly higher in group with a high body fat when compared to those with normal and low values. All anthropometric indices showed significant correlation with fat mass, fat free mass, total and regional body fat percent (P<0.001). After adjustment for age and family socioeconomic status, a high fat mass especially, truncal fat, was positively associated with triglyceride and blood pressure.

Conclusion

Adiposity, especially truncal adiposity, which can be assessed by simple measures such as Body Mass Index (BMI) and Waist Circumference (WC) may predispose adolescent girls for demonstration of metabolic abnormalities and consequently cardiovascular diseases.     

Comparison of Classic Sweat Test and Crystallization Test in Diagnosis of Cystic Fibrosis

Objective

Sweat chloride measurement is considered a standard diagnostic tool for cystic fibrosis (CF). This study was performed to compare sweat chloride values obtained by quantitative pilocarpine iontophoresis (classic test) with sweat crystallization detected by direct observation of a drop of perspiration under light microscopy in patients with and without CF.

Methods

The tests using both techniques were performed simultaneously in patients with and without CF. Cutoff values of ≥60 mmol/L of chloride concentration for the classic sweat test was considered for diagnosis of CF. In crystallization method, observation of typical dendritic forms of salt crystals under light microscopy was interpreted positive.

Findings

Sixty patients suspected to CF (31 males and 29 females) with age range of 9 months to 2 years underwent the sweat test using both techniques. Median sweat chloride values was 26.13+10.85 in group with negative and 72.76+12.78 mmol/L in group with positive sweat test, respectively. All the patients who had positive sweat test in classic method showed typical dendritic forms of salt crystal in sweat crystallization test, which provided the test with 100% sensitivity (95%CI: 93.1–100). Only one of the 31 subjects with negative results for classic sweat test had positive result for crystallization sweat test, which provided the test with 96.7% specificity (95%CI: 92.9–100). Time spent to perform the crystallization test was significantly shorter than the classic method whereas its cost was also lower than the second method.

Conclusion

There was a good correspondence between two studied methods of sweat test. These results suggested the sweat crystallization test as an alternative test for detecting CF disease with high sensitivity and specificity.     

The Role of Marital Status,Literacy, and Urbanity in Suicidal Behavior by Burns in the Province of Khorasan,Iran

A prospective study of all suicidal behaviors by burns requiring hospitalization was conducted in the province of Khorasan, Iran, from March 21, 2005 to March 20, 2006, to examine marital status, urbanity and literacy among these patients. Data were obtained through interviews during the course of hospitalization. A total of 130 patients with suicidal behavior by burns were identified (incidence rate of 2.9 per 100,000). Females had a higher rate of suicidal behavior by burns than males (4.2 vs. 1.6 per 100,000, P < 0.001). The rate of suicidal behavior by burns was higher among single persons than married persons (4.3 vs. 3.5 per 100,000). The rate of suicidal behavior by burns among the rural population was slightly higher than the urban population (3.2 vs. 2.7 per 100,000). The high rate of suicidal behavior by burns among young, married women in Khorasan is a social tragedy.     

Pathologic Evaluation of Appendectomy Specimens in Children: Is Routine Histopatholgic Examination Indicated?

Objective

Acute appendicitis is the most common cause of abdominal surgery in children. Similarity between signs and symptoms of appendicitis and other common pediatric illnesses, atypical manifestations of appendicitis in young children, and children''s inability to give precise explanation for their symptoms contribute to considerable delay in proper diagnosis and increased rate of perforation. Current study reports the surgical and pathological findings of appendectomies in the largest Children''s Hospital in Iran. It also evaluates whether common protocol for pathologic evaluation following appendectomy is beneficial.

Methods

Pathologic reports of 947 appendectomies, performed with the presumptive diagnosis of acute appendicitis, were gathered. Correlation between surgical and pathologic findings was assessed. Demographic characteristics of patients between surgical and pathological subgroups were also compared.

Findings

The mean age of participants was 6.9±3.5 years. Eighty seven (25.5%) children had abnormal pathological findings and normal surgical report. None of miscellaneous findings including appendicular carcinoid tumor 3 (0.3%), oxyuriasis 2 (0.2%), and mycobacterial infection 4 (0.5%) were recognizable during the surgery. Of all pathologically confirmed cases with perforated appendicitis, 9.7% were not detected during the surgery.

Conclusion

In current study, acute appendicitis was the most common pathological diagnosis, however, high normal appendectomy rate along with noticeable proportion of surgically missed perforated appendicitis and unusual histopathologies strongly supported routine histological examination.     

A 10-year single center survey of pediatric patients with histiocytic disorders in Iran

Childhood histiocytosis is a rare and diverse group of proliferative disorders, characterized by accumulation and infiltration of antigen-presenting cells or antigen-processing cells, which can affect any tissue or organ. This study was performed in order to investigate the clinical characteristics of Iranian children with different types of histiocytic disorders. Thirty-five patients, with a median age of 3.5 years, who were referred and diagnosed with histiocytic disorders in a referral Children's Hospital in Iran from 1997-2006, were investigated in this study. According to the World Health Organization classification, 27 patients were in class 1, followed by 6 patients in class 2, and 1 patient in class 3. Moreover, 1 patient was diagnosed with sinus histiocytosis with massive lymphadenopathy. Bone lesions were the most common manifestation, which were detected in 15 cases, followed by skin lesions (11 cases) and fever (10 cases). Nonspecific findings like hepatomegaly and splenomegaly were found in 15 cases. Different types of treatment protocols were used according to the diverse groups of histiocytic disorders and different stages of disease, including surgical excision, radiotherapy, chemotherapy, and stem cell transplantation. Twelve patients did not respond well to the treatment and subsequently died due to complications of their disease. Although histiocytosis is considered a rare condition, it can be problematic for pediatric hematologists because of the unknown etiologies and pathogenesis, variable classifications and subtypes, diagnostic difficulties, poor therapeutic responses with high mortality, and some complications after different therapeutic protocols.     

Bilirubin/Albumin Ratio for Predicting Acute Bilirubin-induced Neurologic Dysfunction

Objective

The aim of this study was to evaluate the bilirubin albumin (B/A) ratio in comparison with total serum bilirubin (TSB) for predicting acute bilirubin-induced neurologic dysfunction (BIND).

Methods

Fifty two term and near term neonates requiring phototherapy and exchange transfusion for severe hyperbilirubinemia in Children''s Medical Center, Tehran, Iran, during September 2007 to September 2008, were evaluated. Serum albumin and bilirubin were measured at admission. All neonates were evaluated for acute BIND based on clinical findings.

Findings

Acute BIND developed in 5 (3.8%) neonates. B/A ratio in patients with BIND was significantly higher than in patients without BIND (P<0.001). Receiver operation characteristics (ROC) analysis identified a TSB cut off value of 25 mg/dL [area under the curve (AUC) 0.945] with a sensitivity of 100% and specificity of 85%. Also, according to the ROC curve, B/A ratio cut off value for predicting acute BIND was 8 (bil mg/al g) (AUC 0.957) with sensitivity of 100% and specificity of 94%.

Conclusion

Based on our results, we suggest using B/A ratio in conjunction with TSB. This can improve the specificity and prevent unnecessary invasive therapy such as exchange transfusion in icteric neonates.