Biomedical subjects

Nuray O Kanbur

Publications and source records attributed to Nuray O Kanbur.

7 recordsLinked to original sources

PubMed2005

Evaluation of mandibular bone density to predict osteoporosis in adolescents with constitutional delayed growth.

OBJECTIVE: The aim of this study is to evaluate the correlation between constitutional delayed growth (CDG) and mandibular bone trabeculation as well as bone density on panoramic radiographs using a computer software program. METHODS: Panoramic radiographs obtained from 25 patients with CDG and 25 healthy adolescents were evaluated for this study. Patients were selected from admission to Hacettepe University, Faculty of Medicine, Section of Adolescent Medicine in the first half of the year 2002. All panoramic radiographs were taken under standard conditions, and were randomized and then converted to digital images for density analysis using a scanner. The images were transferred to Osiris computer software program for the evaluation of bone density from 4 different regions on the mandible (right and left mandibular angle and condyle). RESULTS: The CDG group had higher values for the risk of osteoporosis considering the right (t=3.360, p=0.002) and the left condyle (t=3.620, p=0.001) (t-test for independent samples). It was also seen that the CDG group was again at higher risk in comparison to the control group when left mandibular angle values were measured (z=-2.447, p=0.014) (Mann Whitney-U test). CONCLUSION: We suggest that panoramic radiographs, which are transformed into digital format, can be valuable and economic tools for detecting the risk of osteoporosis in adolescents with CDG.

Adolescent↗

PubMed2004

The effect of tamoxifen on sex hormone binding globulin in adolescents with pubertal gynecomastia.

We investigated the relationship between sex hormone binding globulin (SHBG) and pubertal gynecomastia in 21 adolescents evaluated longitudinally. Thirteen patients were given tamoxifen treatment after grading according to the Nydick classification (group 1). Group 2 consisted of eight patients followed without treatment. Gynecomastia existed bilaterally in 15 patients. There was a statistically significant breast size reduction in both groups. There was a significant decrease in serum SHBG only in group 2. These findings suggest that serum SHBG is increased by tamoxifen treatment in male adolescents. There was a decrease in SHBG levels through the duration of follow up in patients who recovered with or without treatment. However, this decrease was statistically significant in the untreated group, but not in the tamoxifen treated group. In conclusion, we suggest that the pubertal fall in SHBG levels is attenuated by tamoxifen treatment given for pubertal gynecomastia since tamoxifen increases SHBG levels in male adolescents.

Adolescent↗

PubMedDate not supplied

Prevalence of obesity in adolescents and the impact of sexual maturation stage on body mass index in obese adolescents.

OBJECTIVE: Puberty is a high-risk period for the development of obesity. The aim of this study was to determine the prevalence of obesity in adolescents admitted to an outpatient adolescent clinic and investigate the relationships between the increase of body mass index and sexual maturation stages in obese adolescents. MATERIAL AND METHODS: We recruited 6,462 adolescents, aged 9-16 years, admitted to the outpatient clinic of our Adolescent Unit, between May 1999 and September 2000. BMI was calculated as weight per height with weight in kilograms and height in meters. Adolescents with a BMI > or = 95th percentile for age and sex were defined as obese, with BMI's > or = 90th percentile but < 95th percentile were defined as overweight and considered at risk for obesity. Obese adolescents, with endocrine problems identified to cause obesity, were excluded from this study. Pearson correlation coefficients were used to assess the relationships between BMI and age. The differences between the sexual maturation stages were evaluated with Mann-whitney U Test. RESULTS: Out of 6,462 cases screened, 151 obese adolescents were found. Prevalence of obesity for the total sample surveyed was estimated at 2.3%. BMI values were significantly correlated with age in both sexes. In girls, only the increase of BMI values from stage I to stage II was found to be statistically significant. In boys, BMI values did not differ significantly between the sexual maturation stages but the number of obese cases were high in stages I and II. DISCUSSION AND CONCLUSION: The pubertal growth spurt (timing determined by sexual maturation stage) effects the amount of fat accumulation and the distribution of fat in different ways in boys and girls. So, not only the age and sex but also the sexual maturation stage has to be taken into account while evaluating the BMI values for investigating the risk of obesity in puberty.

Adolescent↗

PubMedDate not supplied

The importance of the measurement of the circumference of arm, arm muscle area and skinfold thickness during puberty.

Several methods are available to study lean and adipose tissue component of the upper arm, but the use of a specific technique is mostly determined by time and financial expense. Besides, anthropometric techniques (arm muscle area, mid-arm circumference and the triceps skinfold thickness), which are the most practical, simple, inexpensive and noninvasive, x-ray, ultrasound scanning, computed tomography (CT), or magnetic resonance images (MRI) are also used to determine separate measures of muscles, adipose tissue, and bone area. These radiographic methods are expensive and suitable only for research studies. This short review will try to stress the importance of the measurement of the circumference of arm, arm muscle area and skinfold thickness during puberty and adolescence.

Adolescent↗

PubMedDate not supplied

Osteocalcin. A biochemical marker of bone turnover during puberty.

During bone remodelling, osteocalcin is produced by osteoblasts and its level increases during the events characterized by rapid bone turnover. Osteocalcin is a bone matrix protein, which is specific for bone metabolism and it is not influenced by metabolic bone disorders. Osteocalcin is an important marker of bone turnover in physiological and pathological conditions. Physiologically, serum osteocalcin was increased in children, particularly during the first year of life and during puberty, when evolution of the concentration was related to rapidity of physical growth. Evidence of a correlation with growth rates comes from the observation that serum osteocalcin levels parallel the height velocity curve, with higher values in childhood and during adolescence, that later fall to adult values. There are previous studies reporting that there is age- and sex-dependent change in serum osteocalcin levels in children and adolescents with a pattern resembling height velocity curves for children and serum osteocalcin elevation coincides with the pubertal growth spurt. These findings demonstrate that pubertal development and sex should be taken into account rather than chronological age when serum levels of osteocalcin are evaluated. In most of the studies relationships among osteocalcin and chronological age and bone age, but not pubertal developmental stage (sexual maturation stage) were investigated. The aim of our study was to determine whether osteocalcin is a useful marker for the pubertal growth spurt period. In this study, osteocalcin levels in male adolescents were examined in relation to their sexual maturation stage and age. According to our findings, the follow up of osteocalcin levels in relation to sexual maturation stages could be a new method to determine the phase of the pubertal growth spurt. An increase or decrease in osteocalcin levels on consecutive measurements may indicate the child's entering accelerated or decelerated stages of the growth spurt, respectively. We emphasize that the follow up of adolescent growth is made by determination of the sexual maturation stage, and not by age. Osteocalcin is a highly specific, reliable and useful marker for evaluation of the growth spurt and is not influenced by nonosseous disorders.

Adolescent↗

PubMedDate not supplied

Menorrhagia at menarche: a case report.

Dysfunctional uterine bleeding is defined as abnormal endometrial bleeding without any underlying disease. It is particularly a common problem for adolescents and a majority are caused by immature hypothalamic-pituitary-ovarian axis. Usually, it presents as minor alterations of the cycle flow length, but occasionally can be severe enough to require hospitalization. A 12 year-old girl with menorrhagia at menarche was admitted to our Adolescent Unit. She had heavy bleeding for 16 days causing a hemoglobin level of 5.5 gr/dl. She was first treated with blood transfusion and hemostasis was achieved rapidly through high doses of combination oral contraceptives. Whenever menorrhagia occurs at menarche, it is important to exclude an underlying hematologic disease. If there is no response to hormonal therapy in 48 hours there is a need for reevaluation of coagulopathy. In this report, we show how an acute and heavy anovulatory bleeding episode can be controlled and followed-up in an adolescent girl.

Acute Disease↗

PubMedDate not supplied

Refeeding problems in a severe anorexia nervosa case.

Anorexia Nervosa (AN) is an eating disorder of puberty or adolescence. It is characterized by self-induced weight loss; various psychological disturbances including distorted body image, fear of obesity, active pursuit of thinness and loss of recognition of a number of body enteroreceptive sensations; and secondary physiological abnormalities. The treatment of AN includes individual psychotherapy, family therapy, and nutritional rehabilitation. Hospital treatment is required when the patient's medical condition is in danger due to hypovolemia or hypotension. If cardiac arrhythmias occur without electrolyte disturbances or if oral therapy fails, nutrition should be repleted by the safest method available. This can be done by nasogastric tube or intravenous hyperalimentation. The management of AN is challenging, because the treatment process and anticipated outcome is in direct conflict with the sufferer's own wishes. A comprehensive treatment plan including both psychiatric and medical approaches is necessary. We report a severe AN case, who has refeeding problems after a three months' hospitalisation period. She was admitted to the child intensive care unit due to deterioration of her vital signs. We tried to solve her problems as a team, and believe that AN has a number of crucial problems thus requiring a multi-faceted treatment approach.

Adolescent↗