Bone mineral density of Brazilian girls with juvenile dermatomyositis

We measured bone mineral density (BMD) in girls with juvenile dermatomyositis (JDM) considering multiple factors in order to determine if it could be used as a predictor of reduction in bone mass. A cross-sectional study of lumbar spine BMD (L2-L4) was conducted on 10 girls aged 7-16 years with JDM. A group of 20 age-matched healthy girls was used as control. Lumbar spine BMD was measured by dual-energy X-ray absorptiometry. Weight, height and pubertal Tanner stage were determined in all patients and controls. Duration of disease and mean daily and cumulative steroid doses were calculated for all patients on the basis of their medical charts. JDM activity was determined on the basis of the presence of muscle weakness, cutaneous vasculitis and/or elevation of serum concentration of one or more skeletal muscle enzymes. Seven patients demonstrated osteopenia or osteoporosis. Lumbar BMD was significantly lower in the JDM patients than the age-matched healthy control girls (0.712 vs 0.878, respectively; Student t-test, P = 0.041). No significant correlation between BMD and age, height, Tanner stage, disease duration, corticosteroid use, or disease activity was observed in JDM girls, but a correlation was observed between BMD and weight (Pearson's correlation coefficient, r = 0.802). Patients with JDM may be at risk for a significant reduction in BMD that might contribute to further skeletal fragility. Our results suggest that reduced bone mass in JDM may be related to other intrinsic mechanisms in addition to steroid treatment and some aspects of the disease itself may contribute to this condition.

PCR identification of Mycobacterium tuberculosis complex in a clinical sample from a patient with symptoms of tuberculous spondylodiscitis

A 42-year-old male complaining of thoracic spine pain was admitted to the hospital for evaluation. An X-ray and computer tomography of the thoracic spine showed spondylodiscitis of the L3 lumbar and L2-L3 intervertebral disk. The tuberculin skin test (PPD) was strongly positive. A radioscopy-guided fine needle aspirate of the affected area was cultured but did not reveal the cause of the disease. Two biopsy attempts failed to reveal the cause of the disease by culturing or by acid-fast-resistant staining (Ziehl Neelsen) of the specimens. A third biopsy also failed to detect the infectious agent by using microbiological procedures, but revealed the presence of a 245-bp amplicon characteristic of the Mycobacterium tuberculosis complex after PCR of the sample. The result demonstrates the efficacy of PCR for the identification of M. tuberculosis in situations in which conventional diagnosis by culturing techniques or direct microscopy is unable to detect the microorganism. Following this result the patient was treated with the antituberculous cocktail composed by rifampicin, pirazinamide and isoniazid during a six-month period. At the end of the treatment the dorsalgia symptoms had disappeared.

Lack of relationship between glycemic control and bone mineral density in type 2 diabetes mellitus

We assessed the effect of chronic hyperglycemia on bone mineral density (BMD) and bone remodeling in patients with type 2 diabetes mellitus. We investigated 42 patients with type 2 diabetes under stable control for at least 1 year, 22 of them with good metabolic control (GMC: mean age = 48.8 ± 1.5 years, 11 females) and 20 with poor metabolic control (PMC: mean age = 50.2 ± 1.2 years, 8 females), and 24 normal control individuals (CG: mean age = 46.5 ± 1.1 years, 14 females). We determined BMD in the femoral neck and at the L2-L4 level (DEXA) and serum levels of glucose, total glycated hemoglobin (HbA1), total and ionic calcium, phosphorus, alkaline phosphatase, follicle-stimulating hormone, intact parathyroid hormone (iPTH), 25-hydroxyvitamin D (25-OH-D), insulin-like growth factor I (IGFI), osteocalcin, procollagen type I C propeptide, as well as urinary levels of deoxypyridinoline and creatinine. HbA1 levels were significantly higher in PMC patients (12.5 ± 0.6 vs 7.45 ± 0.2% for GMC and 6.3 ± 0.9% for CG; P < 0.05). There was no difference in 25-OH-D, iPTH or IGFI levels between the three groups. BMD values at L2-L4 (CG = 1.068 ± 0.02 vs GMC = 1.170 ± 0.03 vs PMC = 1.084 ± 0.02 g/cm²) and in the femoral neck (CG = 0.898 ± 0.03 vs GMC = 0.929 ± 0.03 vs PMC = 0.914 ± 0.03 g/cm²) were similar for all groups. PMC presented significantly lower osteocalcin levels than the other two groups, whereas no significant difference in urinary deoxypyridine was observed between groups. The present results demonstrate that hyperglycemia is not associated with increased bone resorption in type 2 diabetes mellitus and that BMD is not altered in type 2 diabetes mellitus.

Longitudinal evaluation of hepatic osteodystrophy in children and adolescents with chronic cholestatic liver disease

Bone mass loss is a major complication of chronic cholestatic liver disease (CCD). However, the long-term impact of CCD on bone mass acquisition is unknown. We longitudinally assessed bone mineral density (BMD) and factors involved in bone remodeling in 9 children and adolescents with CCD Child-Pugh A (5 boys/4 girls) and in 13 controls (6 boys/7 girls). The groups were evaluated twice, at baseline (T0) and after 3 years (T1), when osteocalcin, deoxypyridinoline, 25-hydroxyvitamin-D, parathyroid hormone, insulin-like growth factor-I (IGF-I), and BMD (L1-L4, proximal femur and total body) were determined. Serum levels of receptor activator for nuclear factor kB ligand (RANKL) and osteoprotegerin were measured only at T1. Lumbar spine BMD was reanalyzed twice: after adjustment for bone age and to compensate for the height factor. Volumetric density was also estimated mathematically in L2-L4. The BMD of L1-L4 was lower in the CCD group (Z-score at T0: control = -1.2 ± 0.8 vs CCD = -2.2 ± 1.4, P < 0.05; T1: control = -0.7 ± 0.8 vs CCD = -2.1 ± 1.1, P < 0.05). Osteocalcin and deoxypyridinoline were similar for the two groups. The CCD group presented lower IGF-I (Z-score at T1: control = 1.4 ± 2.8 vs CCD = -1.5 ± 1.0, P < 0.05) and RANKL (control = 0.465 ± 0.275 vs CCD = 0.195 ± 0.250 pM, P < 0.05) than control. Children with compensated CCD Child-Pugh A showed early impairment of bone acquisition, with the impact being more severe in an initial phase and then tapering in a slowly progressive way. Reduction in endocrine IGF-I has a crucial role in this process.

A morphometric study of the lumbar spinous process in the Chinese population

Our goal was to analyze the anatomical parameters of the lumbar spine spinous process for an interspinous stabilization device designed for the Chinese population and to offer an anatomical basis for its clinical application. The posterior lumbar spines (T12-S1) of 52 adult cadavers were used for measuring the following: distance between two adjacent spinous processes (DB), distance across two adjacent spinous processes (DA), thickness of the central spinous processes (TC), thickness of the superior margin of the spinous processes (TS), thickness of the inferior margin of the spinous processes (TI), and height of the spinous processes (H). Variance and correlation analyses were conducted for these data, and the data met the normal distribution and homogeneity of variance. DB decreased gradually from L1-2 to L5-S1. DA increased from T12-L1 to L2-3 and then decreased from L2-3 to L4-5. The largest H in males was noted at L3 (25.45±5.96 mm), whereas for females the largest H was noted at L4 (18.71±4.50 mm). Usually, TS of the adjacent spinous process was lower than TI. Based on the anatomical parameters of the lumbar spinous processes obtained in this study, an “H”-shaped coronal plane (posterior view) was proposed as an interspinous stabilization device for the Chinese population. This study reports morphometric data of the lumbar spinous processes in the Chinese population, which provides an anatomical basis for future clinical applications.

Sensibilidade dos microssatélites para determinar a pureza varietal em sementes de milho

Em um sistema de produção de sementes, o limite de contaminação varietal em lotes de linhagens de milho é zero, de modo que a presença de apenas uma semente de genótipo estranho acarreta a reprovação do lote. Várias técnicas vêm sendo estudadas para determinar a pureza varietal, incluindo marcadores moleculares baseados em polimorfismo de DNA. Nessa pesquisa foi avaliada a sensibilidade da técnica de microssatélites para detectar a presença de sementes de outros genótipos em lotes de linhagens de milho. Utilizaram-se quatro linhagens (L1, L2, L3 e L4), onde as sementes da L2 eram contaminantes da L1 e, as da L4, contaminantes da L3. Para simulação de diferentes níveis de contaminação, 0, 1, 2, 5 e 10 sementes do genótipo estranho foram misturadas a "bulks" de 100 sementes da linhagem comercial. Em seguida, efetuou-se a extração de DNA das amostras de sementes das quatro amostras preparadas. Por outro lado, para simular níveis inferiores de contaminação, foram misturados DNA do genótipo contaminante em níveis de 0,01; 0,013; 0,02; 0,04; 0,1; 0,2; 1; 2; 5; 10 e 100%. A amplificação dos microssatélites foi realizada utilizando o iniciador BNLG125 para a L1+L2 e o BNLG240 para L3+L4. Observou-se que os marcadores microssatélites foram eficientes para determinar a pureza varietal de lotes de sementes de linhagens de milho, utilizados neste estudo, com sensibilidade para detecção de concentrações de DNA iguais ou superiores a 0,01%, apresentando nitidez e repetibilidade, especialmente com a utilização de gel de poliacrilamida. Ao mesmo tempo, a presença de DNA estranho nas amostras constituídas por "bulks" foi detectada eficientemente por essa técnica, indicando a possibilidade de sua utilização em testes de rotina para avaliar a presença de outras cultivares, em lotes de sementes de milho.