Challenges and accurate estimates of mortality and case-fatality rates due to COVID-19.

Many reasons restrict obtaining an accurate estimate of Case Fatality Rate (CFR) and Mortality Rate (MR) by COVID-19. The main concern is the number of infected people and deaths. We aimed to discuss some solutions for accurate estimating of CFR and MR.

Predictors of transition in smoking stages in Iranian adolescents: latent transition analysis.

This study determined the prevalence of smoking stages in adolescents, the probability of transition across stages and the personal and environmental predictors of transition. A school-based study was conducted in 2010-11 using a random sample of 5197 students (mean age 15.7 years) in Tabriz city. The students were evaluated twice, 12-months apart. The latent transition analysis model revealed 9 interpretable statuses for the measurement of smoking stages. Prevalence data showed that at the first and second assessments 75.1% and 66.8% of students respectively were in the committer stage, while 4.8% and 7.1% respectively were daily smokers. Over 12 months, 10.1% of the never smokers became experimenters and 1.7% became regular smokers, while 17.0% of experimenters became regular smokers. The analysis also showed factors associated with transitions in cigarette smoking stages. Although the prevalence of smoking was low in our adolescents, the rate of becoming a smoker over 1 year was high.

Social determinants and health-related dimensions of quality of life in adult patients with haemophilia.

The availability of safe and effective factor replacement therapies, in persons with haemophilia (PWH), has in some countries answered the basic need for treatment of these patients. The findings suggest that adult patients who have always been on prophylaxis reported significantly better physical functioning, and thus better quality of life. This study is designed to evaluate the QoL in adult PWH, by focusing on social determinants of QoL and their relationship with health-related dimensions, in Tabriz, Iran. The survey instrument was a self-report 36 items questionnaire, 'A36 Hemofilia - QoL', which is a disease-specific questionnaire for the assessment of the health-related QoL in adults living with haemophilia. A total of 100 haemophilia A and B patients, aged over 17 years participated in this study within 1 year. QoL total score was 71.88 (±26.89 SD). Patients who treat in our Hemophilia Treatment Center, had better QoL score (P = 0.000), and education has a significant impact on the social aspects of QoL (P = 0.18). The QoL was very poor in urban area in contrast to patients who lived in the city (54.45 vs. 74.21 respectively). Single patients have a better QoL than married patients (76.56 vs. 68.50 respectively). Our results showed that low education and lack of awareness of the diseases among PWH lead to reduce of QoL and more disease complications. More and wider treatment and psychological care for improving quality of life of these patients are seriously recommended.

Predictors of transition in smoking stages in Iranian adolescents: latent transition analysis

يحدد الباحثون في هذه الدراسة معدل انتشار مراحل التدخين لدى المراهقين، واحتال التحول من مرحلة إلى أخرى، والعوامل الشخصية والبيئية المنبئة بالتحول. وقد أجرى الباحثون دراسة في المدارس في عامي 2010 - 2011 واستخدموا عينة تتألف من 5197 تلميذا [العمر الوسطي 15.7 عاما]في مدينة تبريز. وقيم الباحثون التلاميذ مرتين يفصل بينها 12 شهرا. وقد أظهر نموذج تحليل التحول الخافي تسع حالات يمكن تفسرها لقياس مراحل التدخين. كما أوضحت بيانات معدلات الانتشار أن نسبة الطلاب الذين كانوا في مرحلة الملتزمين بلغت في التقييم الأول 75.1 % وفي التقييم الثاني 66.8 %، وأن نسبة المدخنين يوميا في التقييم الأول 4.8 % وفي التقييم الثاني 7.1 %.وعلى مدى الأشهر الاثني عشر كان 10.1 % من التلاميذ الذين لم يسبق لهم التدخين قد أصبحوا من المجربين، كما أصبح 1.7 % منهم من المدخنين الاعتيادين، في حين أصبح 17 % من المجربين مدخنين اعتيادين. كما أوضح التحليل العوامل التي رافقت التحولات في مراحل تدخين السجائر، فرغم أن معدل انتشار التدخين كان منخفضا لدى هؤلاء المراهقين، فإن معدل التحول إلى المدخنين على مدى سنة كان معدلا مرتفعا

ABSTRACT This study determined the prevalence of smoking stages in adolescents, the probability of transition across stages and the personal and environmental predictors of transition. A school-based study was conducted in 2010–11 using a random sample of 5197 students (mean age 15.7 years) in Tabriz city. The students were evaluated twice, 12-months apart. The latent transition analysis model revealed 9 interpretable statuses for the measurement of smoking stages. Prevalence data showed that at the first and second assessments 75.1% and 66.8% of students respectively were in the committer stage, while 4.8% and 7.1% respectively were daily smokers. Over 12 months, 10.1% of the never smokers became experimenters and 1.7% became regular smokers, while 17.0% of experimenters became regular smokers. The analysis also showed factors associated with transitions in cigarette smoking stages. Although the prevalence of smoking was low in our adolescents, the rate of becoming a smoker over 1 year was high.

RÉSUMÉ La présente étude a déterminé la prévalence des stades de consommation du tabac chez des adolescents, la probabilité de transition entre les différents stades et les facteurs prédictifs de transition personnels et environnementaux. Une étude a été menée en milieu scolaire en 2010 et 2011 à partir d'un échantillon aléatoire de 5197 élèves (âge moyen : 15,7 ans) dans la ville de Tabriz. Les élèves ont été évalués à deux reprises, à 12 mois d'intervalle. Le modèle d'analyse des transitions latentes a permis de dégager neuf statuts interprétables afin de mesurer les stades de consommation de tabac. Les données sur la prévalence ont révélé que lors de la première et de la deuxième évaluation, 75,1 % et 66,8 % des élèves respectivement étaient des non-fumeurs décidée à ne pas commencer, tandis que 4,8 % et 7,1 % respectivement étaient des fumeurs quotidiens. Sur une période de 12 mois, 10,1 % des personnes n'ayant jamais fumé ont expérimenté le tabac et 1,7 % sont devenus des fumeurs réguliers, tandis que 17,0 % des personnes ayant expérimenté le tabac sont devenus des fumeurs réguliers. L'analyse a mis en évidence des facteurs associés aux transitions entre les stades de consommation de tabac. Si la prévalence du tabagisme était faible chez nos adolescents, le taux de transition vers le statut de fumeur sur une période d'un an était en revanche élevé.

Applications and emerging trends of hyaluronic acid in tissue engineering, as a dermal filler and in osteoarthritis treatment.

Hyaluronic acid (HA) is a naturally occurring biodegradable polymer with a variety of applications in medicine, including scaffolding for tissue engineering, dermatological fillers and viscosupplementation for osteoarthritis treatment. HA is available in most connective tissues in body fluids such as synovial fluid and the vitreous humor of the eye. HA is responsible for several structural properties of tissues as a component of extracellular matrix and is involved in cellular signaling. Degradation of HA is a stepwise process that can occur via enzymatic or non-enzymatic reactions. A reduction in HA mass or molecular weight via degradation or slowing of synthesis affects physical and chemical properties such as tissue volume, viscosity and elasticity. This review addresses the distribution, turnover and tissue-specific properties of HA. This information is used as the context for considering recent products and strategies for modifying the viscoelastic properties of HA in tissue engineering, as a dermal filler and in osteoarthritis treatment.

Substance abuse in high school students in association with socio-demographic variables in northwest of iran.

BACKGROUND: Substance abuse in adolescents and its often tragic consequences, including addiction, is one of the preventable major public health problems. The aims of this paper were to estimate the prevalence of substance abuse and to evaluate its some associated factors in adolescents of Tabriz City (northwest of Iran). METHODS: A self-administered questionnaire was completed in 4903 randomly selected students with mean age of 15.7 years old. The aim of the questionnaire was obtaining information on substance abuse, socio-economical information, cigarette smoking behavior, general risk taking behavior, self-esteem, attitude towards smoking and self-injury as well as demographical characteristics. RESULTS: Prevalence of substance abuse was 1.4% (95% CI: 1.1-1.7) which was different statistically significant between boys (2.4%) and girls (0.6%) (P<0.001). Older age (OR=1.43), not living with parents (OR=2.34), having general risk taking behavior (OR=2.26), higher smoking stage (OR=2.39), lower self-esteem (OR=1.09) and positive attitude toward smoking (OR=1.08) were factors associated with student's ever use of substance. CONCLUSION: The result has shown low prevalence of substance abuse in Iranian adolescents. Our findings showed some associated factors such as lower self-esteem with adolescent's substance abuse.